The Quintessential BigMac

Welcome to The Quintessential BigMac blog. This site is dedicated to the illustrious and knowledgeable Big man of bicycles. Here you will find a quick reference to all things BigMac covering many aspects of cycling from A to Z.

Friday, February 18, 2005

BigMac on Tubulars and such.

Want to know a little something about tubular rims, tires, and wheels? Check out what the Big man says on...

Tubular Tires
Tubular rims
Tubular vs Clincher
Climbing wheels
Composite rims
And Wheels for Sandy

William

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Tubular tires
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The "Dugast" sewups are in fact rebuilt Clements. The "Griffo" you are likely referring to are made in Taiwan under the "Challenge" label but are in fact based on the old Clement molds. The saddest day in cycling history was the day Clement closed its doors...followed by the day Mavic bought Wolber and decided Wolber sewup production would also cease.

The Dugasts are extraordinarily pricey and difficult to find but he actually uses the Clement casings (both silk and cotton versions) for his 'cross sewups. He also uses Wolber cotton casings on some road sewups. Repair casing as needed using same grade thread, insert new latex tube, latex seal case, apply vulcanized tread using similar albeit not identical knobby tread pattern. The result is a sewup that is arguably higher quality (more consistent) than the original model. The Challenger Griffo uses same shape and identical tread pattern to the Clement original but otherwise bares little resemblance to the Clement original.

To your question regarding repairability, yes these are each 'repairable' or conventional sewups that may be repaired by pulling back bias tape, cutting threads, repairing tube, sewing up casing and tape. I'm certainly not going to tell you what you should and should not buy or use but if ride quality, cornering performance and repairability of your tubular tires is of import to you, I would encourage you to avoid anything Tufo. Tufo is a reincarnation of the old Barum tubulars that promised tubeless superiority due to reduced mass, lower cost and similar puncture resistance. Unfortunately, the reality is the casings are stiff, production consistency poor and cost is similar to far better performing true sewups. Once you've experienced a quality sewup like NOS Clement, Dugast, NOS Wolber or Conti Comps I would doubt you'll ever consider a Tufo again. On the other hand, most Tufo riders seem to be wire-on converts as Tufo's ride and perform very similar to their beaded cousins, only 50 grams lighter. For 'cross racers the Dugasts (glued, NOT taped) are the winning choice as they can be run safely at insanely low pressures for remarkable hook-up in the really loose stuff.

Ride on!


Douglas:

After all these years you've left the dark side and once again embraced the enlightened few who swear by sewups. Those Dugasts are basically rebuilt Campiones, at least the casing. My limited experience with Andre's tires suggest they ride identically to the famed Clements. In fact I am going to be sending him several pairs of my worn Campiones this summer for rebuilding, there is/was nothing like that tire...ever. The Wolber Champione was nearly identical with a cotton casing, I understand Andre will also rebuild these, if so I will be set for sewups until perhaps the next millenium. Cost? Does it really matter? Normally, I am the most ardent value conscience, at least relative to most roadie's spending habits, but there is simply no substitute for the finest sewups that ever lived. Record v Chorus or Centaur? No brainer, the lesser priced parts offer same performance for less $$, often with greater durability. The super value Ritchey Pro seat pillar is another no-brainer at $40 a pop. Heck, I don't even wear Assos bibs any longer since finding Boure and Etxe-Ondo are equally comfy for half the price. But Andre recreating the legendary Clement and Wolber sewups...there is no price on perfection. I would however concur with previous gentleman, real sewups deserve real glue, that tape seems like a nice concept -- not unlike clinchers -- but does it deliver the goods? I think I'd give the demoing of such newer techniques to the young kids who more readily recover from broken bones before I'd trust tape to safely hold my tires in heat, cold and/or damp conditions...at least I know the glue works if properly applied. Be safe out there and welcome back to sewups.

Ride on!
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On Tubular rims
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RWL:

Actually the "flyweight" sewup rims of yore is mostly a fable. The actual superlight sub 300g rims were very rare, very flexible and for very limited situations. Others, the Mavic GEL's for example had claimed masses of 280g which in typical Mavic-speak meant they were in reality 315-320 grams of spaghetti like flex. The very popular GL was in reality 365g rim despite its claimed 330g mass. The GP4 was around 440 grams and the famous Paris-Roubaix was a portly 490g, although that rim won more races in its day than any rim in history...perhaps rider watts and durability are in fact more important

Mavic is famous for their claimed masses, when Reflex was introduced, it was actually considered the sucessor to the GL330, claimed to be more durable and only slightly heavier at 375g, per Mavic Fr. Then when the same rim arrived on US shores, the US distributor claimed its mass was 395g...same identical rim and in fact I believe Mavic still claims this is the true mass of said rim, with 410g for the ceramic brake surface version. In reality, the standard silver anodized Reflex is around 420g, a pretty light and relative strong rim. By comparison, an Open Pro is approximately 470-480g, despite what Mavic claims (450?). This is true of basically anything wearing a Mavic label, add 8-10% and you'll have true weight...if it really matters to you.

NOS rims? The really good Ambrosio's of the day were all over 400 grams, Wolber offered a couple of light rims in the 350g class but they were similar to Mavic GL's in terms of strength. The Fiammes were very spotty qc and they did offer some very low mass rims but their best rims (durable) were >400g. Super Champion had some great rims in 60's but most 'modern' Super Champions are rebadged Wolber (company was bought by Wolber in around '72) or Mavic (Wolber was bought by Mavic in mid 80's and they kept SuperChampion name for Asian market up till late 90's). The best lightweight sewup rims were Campy, they had a couple of true 350g rims that were reasonably strong, had great vertical braking surfaces and always perfectly round and true. These were all produced in-house till early 90's when FIR took over production with nearly same superlative quality but slightly higher mass models due to dish issues.

The more modern sewup rims are a bit dicey. I avoid Ambrosio, they too were bought in mid 90's and most of their rims are pinned and glued. They do offer 2 FIR produced rims which are welded but both are clincher models. The Velocity sewup rim is similarly pinned and glued which I do not prefer and my personal experience with Velocity rims is questionable. They are a bit higher quality (more consistent qc) than Sun/Rhyngo but I have yet to see a single Velocity rim arrive in original packaging perfectly round and true. In truth, Mavic's are rarely round and true, but they are more consistently close than Velocity, plus Mavic's are welded which is likely cause for some slight trueness/roundness irregularities which is easily corrected in buildup.

The FIR rims are in my opinion the best available...well actually I love Bontrager rims and especially their pricing but Bontrager unfortunately has not offered a sewup rim...yet (Sr. Jerk had indicated one may be forthcoming?). FIR rims are, ime, the 2nd coming of vintage Campy rims; remarkably true, round and strong. FIR does offer at least 3 alloy sewup rims I am aware of. I do not recall the names of the individual models, one is essentially a 20mm box rim, 13mm tall, very similar to Reflex. A second is an aero V model, 20x20mm, 460g, very strong. The last is the "Concept 2000" model, the front is a traditional aero V, 20x19mm available in 24,28 and 32H drillings. The rear rim is 20x20mm semi-aero (similar shape as Open Pro) with 3mm offset assyemmtric rear drilling for reduced dish. This rim however has a significant downside in that it is designed as a team issue model. Its is very dark grey anodized but with HUGE "CONCEPT 2000" logo, each letter spaced evenly between spoke hole and a reasonably large "FIR" logo as well in very bright yellow. It also appears to not be available for public retail, at least not to my knowledge at this time. There is a clincher version of similar design available to public so hopefully the sewup version may soon follow. I have been using these rims on 2 of my bikes, they are remarkably strong and relatively light -- team mechanics say they arrive incredibly true and they weigh 410g +/- 5g....that includes ss eyelets. I am trying to acquire 15-20 of the rear rims only to ship back to 'States next month but if import duties end up being ridiculous, I will just keep them with me here in Italy and pack only 2 or 3 in our luggage when we return home at the end of August. I would be shipping from my residence in Italy directly to my residence in US and the items would not technically be for resale (friends would be reimbursing my shipping costs only), does anybody know if there is a legal way to avoid import duties for such an event? If I am able to ship these rims, I would be willing to make a few rims available to fellow forum members in September.

Campy's last rim building efforts included the forgettable Barcelona model. this was claimed to be an in-house effort, not sure whether this is true, the result was poor qc and a rim HIGHLY prone to popping rim eyelets. I would avoid this rim although it was a true lightweight at approx 375g.

Unless you can find the Concept 2000 rim, or I am able to ship a few myself, I honestly think prebuilt wheels are the better choice for sewup wheels using modern 43mm drivelines. The Campy Neutron/Nucleon and Bontrager Race X-Lite are excellent offerings, with reduced dish rims, good hubs albeit rather eye-popping prices for a daily wheelset.

Ride on!

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Question by Big D:
Hello, this is a question for Big Mac. I am 6'3" 350lbs+. I am interested in building up a set of tubulars and have found Ital-thecnos online has many different types. Do you think I can build of sturdy wheels with Mavic CXP 30 of Ambrosio rims. If not these rims what do you suggest? What every i build for my second set of wheels I will be going with 36 spokes and i think white industry hubs or DT's

thanks in advance

Big D
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BigD:

You are a prime candidate for the Bontrager rim, if it ever makes it to production or the FIR's, although the 32H maybe a bit too little even with assymetric drilling. You are also a good candidate for the hub upgrade, not for weight but for strength in freehub, flange and flange design for reduced dish. Are you using Campy or Shimano? Use White LTA hub for Campy, Phil Wood hub for Shimano. Lace 3x on driveside, 2x leftside. I would consider using the DT Alpine (I believe that is name of spoke, it features a 13g elbow which both White and Phil are drilled for, the balance of spoke is 14g for standard brass nipple compliance. You will only need these on driveside as non-drive will have lower tension and straight 14g spokes will be fine. You may consider tie and soldering spokes, it makes for a stiffer wheel, possibly stronger although that is debatable, retrueing/servicing can be more problematic and your wheels will DEFINATELY require periodic servicing (spoke replacements) regardless of components used. Sewup rims? Not the Reflex or any other currently available rim. The CXP30's are pretty strong, although really ugly imo...not that it really matters . I would see if you could find NOS 36H Mavic SSC Paris-Roubaix rims. They will be pricey but far more durable than alternatives. The vintage Ambrosio Synthesis Durex was also available in 36H and extremely strong. There are bunches of NOS Italian rims labeled Galli, Assos, Fiamme, Nisi....most were of marginal quality and considerably too light for your requirements. Wish I could help with direct source but until I can easily ship the FIR's, Google is probably your best source and the Mavic P-R's are the best possible choice.

I would also suggest minimum 25mm sewups, the recently discontinued Conti Competition 25's are pricey but bomb-proof durable and extremely smooth. NOS Clements(rebuilt and sold as Dugast's by Andre Dugast) are not quite as durable and extraordinarily expensive but worth it given your size. Wolber also made great sewups in their day in 24-27mm widths. Be sure you have enough clearence for fat sewups, if so you will love the ride, response and feel.

It's past midnight now and I'm about to turn into a pumpkin if I don't hit the hay soon.

Ride on!


I am not a Campy historian by any account, I can only marginally recall the Campy rims I have used and most were indeed of exceptional quality. They did go outside for production of most of their rims from late 80's-on, however I am not aware of any specific problems attributed to that outsourcing. The traditional rim names were Record, Corsa and Victory as I recall but then somewhere in late 80's or early 90's the greek naming took over and we saw Omega, Sigma and Lambda. As I recall the Sigma was the priciest followed by Omega and Lambda, in that order. Sigma rims were made by FIR -- pronounced 'feer' if it matters -- the Omega's were apparently produced by Ambrosio before their buyout. I do not know who produced the Lambda series rims. I have put many miles on Sigma Strada and Record Pave's, both with excellent results. The Strada model is around 400g rim, no matter what "series", the Pave's were considerably beefier at maybe 460g. The Sigma, Record, Victory and Omega models all use ss eyelets, canted a bit to relieve spoke fatigue. The Sigma has nice flat braking surface, not machined like modern rims but extruded flat none-the-less, the Record Pave braking surface is a bit rounded. As long as you avoid the Barcelona model rim --produced in-house and apparently same as Neutron/Nucleon front rim but unfortunately not assymetrically drilled like Nucleon rear, it also has tendency to pop eyelets which Nucleon rarely does perhaps due to Campy's propreitary nipple design used on Nucleon -- any Campy sewup rim is a good choice in my book...at least for older chainlines and/or sub 200lb riders.

Update for those inquiring about assymetric drilled sewup rim:

As I previously noted, I will possibly be acquiring 1-2 dozen team issue "Concept" sewup rims, actually I only want the assyemtric drilled rear, I can happily use a standard FIR, Campy or Mavic box section sewup rim up front. I will know more later this week, FIR is located up north in Modena while I'm in Sorrento (south of Naples, north end of Amalfi coast). I do however have my hands on an '04 product catalog. It lists 2 sewup rims, model ST-120 and SRG30. The rim product line will apparently be unchanged for '05 as FIR continues to concentrate on the more profitable pre-built wheel market -- they will have no-less than 11 composite wheel offerings in '05! As for the sewup rims, the ST 120 is a 400g box section rim very comparable to Mavic Reflex. The SRG30 is a semi-aero (30mm deepx20mm wide) 505g rim (545g in clincher model) very similar to Mavic's discontinued CXP33 sewup rim. Braking surface is a full 11mm deep, joint is MIG welded. The best news however is that the SRG30 is available in assymetric drilling in both sewup and clincher versions! Its also available in 6 different colors, if that's your thing. The downside (imo) is that Red Rose Imports (Lancaster, PA) is the US distributor/importer. There is apparently another authorized importer but their alotment is so minute I seriously doubt they import any sewup rims. My personal experience with RRI is not great, they usually import a fraction of a vendors product line and their distribution is painfully slow. I am told they have ordered reasonable quantities of sewup offerings in past so hopefully I am incorrect in my assumption. Of course even if RRI does choose to import the SRG30, in Ferrari red no-less, there is no guarantee they will import the assymetric drilled rim as importing the symmetrically drilled front rim only would require 50% less inventory, no new product sku numbering and eliminate possible LBS confusion and inventory issues. I personally know of 2 BayArea Trek shops who do NOT stock Bontrager rims because of this very issue preferring to stock Mavic rims...but they do use the assyemtric sales pitch to sell Campy and Bontrager pre-builts of course I will update folks early next week if I can easily ship the Concept rims, until then please contact your LBS or RRI directly to see if they will import SRG30 assyemtrics for you....retail price here is 5 Euros less than Mavic Reflex dark anodized.

Ride on!

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Tubular vs Clincher
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I do not know if there has been an emperical study performed that would prove sewups have lower rolling resistance than wire-on, but it is a fact. Speak with engineers at Continental, who produce high quality versions of each design used by pro's worldwide, they will tell you sewups are lower rolling resistance, at least in theory. Places where ultimate speed is the only criteria, velodrome racing for example, only use sewups. It does have something to do with casing design and friction losses due to the loose tube, this is one of the supposed benefits of the new tubeless clinchers. For practical terms, anyone around this forum, including yours truly, is not going to be even fractionally faster based on tire design choice, at least in straightline racing.

If you were however to include high speed descents in your riding regimen, I do believe the sewups will be faster for most aggressive riders due to much improved handling response, feel and performance(grip). I also suspect any triathletes competing over most long courses could gain considerable time using faster rolling sewups as used by every elite triathalete and professional road racer over long TT events.

For most stage events, pro teams generally prefer sewups for 2 reasons, performance and servicability. In reality, the field is nearly even at this years TdF due primarily to Michelin being the largest professional sponsor. All Michelin support contracts REQUIRE teams to use clinchers a minimum of 50% of total miles, some teams much higher. Michelin does not produce sewups however teams are allowed to contract for mock-up sewups that employ cosmetic features of Michelin clinchers, namely logos and tread colors. Yes, pinch-flat prevention, low rolling resistance, handling performance are all important factors but perhaps the biggest factor in choosing sewups among pro teams is ability of wheel to continue to be ridden when flatted while race support attempts to get to rider. If a puncture occurs with a clincher, the wheel can rarely be ridden safely thus rider often must wait helplessly at roadside till a race support vehicle can get to him for assistance. This can mean minutes, not seconds and has often occurred thus far in this years Tour.

On this very forum this topic has often been rehashed with the identical arguments. There are in fact fans in both camps, perhaps a few may even convert to clinchers with soon introduction of Mavic-Michelin road tubeless design. I would not dismiss either design w/o a full hands-on demo of each under your normal riding conditions. The difference in feel is considerable, as is installation and servicabilty. Use whatever works and feels best to you and your needs. Heck whatever gets people on their bikes more often is ALWAYS the best choice. Debating rolling resistance is synonymous with debating whether smooth or file tread offers better performance...it just don't matter.

Ride on!

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Climbing Wheels?
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The best climbing wheels are the ones on the bike of the strongest climber, period!

I'm honestly not trying to rain on your parade, but seriously, the lightest, fastest wheels will not turn a schmuck into Lance Armstrong. A good, sound and reliable hand-built wheelset or a defacto quality prebuilt such as Campy Nucleon or Bontrager Race X-lite sewups will perform equal in most instances to the fanciest cf offerings from Lightweight, ADA, Campy, Reynolds, etc. An aero wheel will have greater speed impact over a long TT or tri course but even that will be 30 seconds on average, perhaps a minute on longer courses. In mountains, the lightweight wheels will feel quicker accelerating forward but honestly the net result may be 10 seconds on a very long course with lots of swicthbacks. You're far better off spending your time in weight room gaining strength and money on a coach or training device to improve your pedalling technique.

Your money to spend as you wish, hope you're not too dissapointed when the latest, lightest "climbing wheels" still leave you dropping off the back of the pack.

Ride on!

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Composite Rims
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I would disagree with the "Jerk" in his assesment of the Bontrager Triple X. I am a big fan of Bontrager alloy wheels and their rims as well, however the Triple X does not share the most important factor in making the alloy prebuilts and rims so good; the Triple X is not assymetrically drilled in rear to reduce dish. They are also not the equivalent of Race XLite's in terms of braking feel and performance.

That's not to say these are not good race only wheels, they are. Their braking performance is similar to Campy Hyperon, much better than the Zipp's. Rim mass is among the lightest, although not as light as the Reynold's Cirro KOM's. Total wheel mass is around 1200g, 50g less than Hyperon although Campy mass is w/skewers, I do not believe Bontrager masses include qr skewers. The Reynolds KOM's are another 150g lighter, albeit w/o skewers. The std Cirro's are 50g less than Triple X, equally stiff laterally, $100 less money although a bit worse in braking performance.

Bontrager has begun using Edco hubs in Triple X and Race XLite, this is same hub Zipp formerly used. The Zipp's were noted for occasional freehub pawl failures thus I'd be a bit concerned about this change. They had previously used DT/Hugi produced hubs.

If you are looking for lightweight composite climbing wheels at "semi-reasonable" pricing, I think the Hyperon is the best choice. Lateral stiffness is noticably higher than Bontrager or Reynold's, the Zipp 303's are terrible in this respect. This is largely due to fact that Hyperon uses an assymetric rear rim that results in lateral stiffness similar to Neutron. The Cirro and Triple X required me to open brake qr during any climbing or heavy load conditions to prevent brake block rub. Why the Triple X is not assymetrically drilled I do not know, seems like a very imprudent decision, imo. If you need something more aero, the Campy Bora G3 is another superb wheel, not overly crosswind friendly however. I personally think alloy rimmed wheels are a better choice, not to mention a FAR better value, for 99% of all users. Of the current available inventory of composite wheels, the Campy's stand alone at front of class, imo.

Ride on!
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Jerk:

In order to get reasonable braking performance from the Hyperon you must jetison the stock cork pads and use Kool Stop Green pads instead. No heat build up issues that I've noticed.

If Trek feels the new Edco hubs do not require assymetric rear rims, why do they use same hub and lacing on '04 Race X-Lites which do have assyemtric rim? The spoke angle on right (drive) side is considerably less angled than on left. I did not check spoke tension to determine exact tension differential between sides but I suspect it is large. The spoke angle on Hyperon are much more similar due to 3mm offset and spoke tension is quite similar. I'd trust the Campy hub for longterm durability/reliability over the Edco as well.

The one item in favor of the Bontrager is its usage of stock j bend spoke on driveside hub. This is typically where spoke failures occur, so having a readily available spoke is far better than Campy's proprietary straight pull type. On the other hand, Campy's better lacing/rim design should be beneficial in mitigating spoke breakage issues. I've had mine for 2 seasons w/o any failures or maintainence issues although I rarely use them, basically limited to competitive DC's with lots of steeps.

I've only demo'd one TripleX sample, which was prior to retail release so perhaps some changes have been made however I doubt it. Granted, my size and weight is greater than most cyclists and I am a bit hard on wheels so take my experiences with a grain of salt.

I'd still buy the Race X-Lite or Neutron sewup wheels before spending nearly twice as much to save maybe 300g per pair of wheels unless I was spending all day riding >10% grade climbs. Safety, durability, reliability, torsional stiffness and cost all favor the alloy versions. Bontrager and Campy make really fine alloy wheels.
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Jerk:

Amazing how you and I have evolved into agreeing on most cycling topics. I still can't use 15cm stems, even my filet'd Cr-Mo 11.5cm stem flexes more than I sometimes prefer, a 15cm would have to use way OS tubing and that would be tooooo uuuugly.

You've even dropped the 3rd person references, or is that just for my benefit saved just for direct response to me. Anyway, Holiday Cheers to you and yours.

Ride on!
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There is no composite rims that is suitable for daily usage amongst the box jockey's. Unless your riding is limited to open stretches of tarmac that never require emergency stopping power, stick with alloy rims.

While all cf rims offer seriously compromised braking, the Lews were the worst ever. This was due to their excessively narrow width. There was no viable reason for this design, a large reason why the company failed, please let us not be reminded of the pedophilia charges that also effected the companies founder. The 17mm rim width is less than optimal given the geometry of all caliper brakes, not to mention that it compromised glueing integrirty for most quality sewups. The Lew wheels should be avoided altogether. When Reynold's/MacLean took over the Lew patents they made several changes, the first and foremost however was was redesigning rims to 19.5mm width for better braking.

If you do use cf rims, install Kool Stop Green pads, the best pad available for composite rims, used by almost every pro team. They still will not stop or modulate like a good alloy rim but at least a 20mm rim width and Green pad give you the best shot at decent braking performance for those cf rim users.

Ride on!

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Wheels for Sandy
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Young Sanford:

Good to hear you are still out enjoying your new rig. Have we not already been down this "which wheels" topic in a 'previous life'?

With all due respect to a few previous posters responses, composite wheels are to be AVOIDED at all costs, no pun intended. Composite wheels are great for race only usage on closed course. Negotiating nasty DC traffic with composite wheels is not only fiscally imprudent, its dangerous. Even if using special brake blocks, the Kool Stop green compound are the most effective ime, the braking performance using rim brakes on composite rims is poor at best. Stick with good reliable and affordable alloy rims for your usage.

The most important consideration should be what you are looking for from these wheels. Something bullet-proof reliable, affordable and long lasting? Hand built 36H wheels by a local experienced wheelsmith is best choice. Avoid the fancy, pricey spokes, use butted 14g up front and non-drive rear, straight 14g driveside 3x laced, 2x non-drive. If you want something "stylish", the Sapim CX-ray spokes are outrageously priced, cool looking, compatible with any hub but will offer compromised longterm durability. They're strong (tensile strength) but brittle and fatigue prone. If one fails, it's usually a quick and easy repair plus with 36 spokes/wheel the wheel generally can be ridden home. Most low spoke count wheels cannot be ridden home if a single spoke fails.

The Topolinos should be avoided for this very reason. These wheels are actually only 2 "spokes"/wheel. A single composite serpentine string per side, if it fails (Spynergy's have had a very suspect service record using similar materials), the wheel must be sent back to factory for repair. No problem for sag supported racers, big problem for recreational rider.

If you have DA10 hubs from your gruppo, use these. If not, the Phil Wood hubs are nearly same price as the new DA10 hubs. I'd choose Phil's for longterm durability and better flange design everyday of week, twice on Sunday's.

If no hubs, pre-builts may be a consideration. I am big fan of the Bontrager Race Lite/Race XLite series as well as Campy's prebuilts. These 2 lines have taken measures to reduce rear wheel dish, something all users of 8+ spd rear clusters should consider, particularly those in your size/weight class.

Lastly I'll make my pitch for the best wheels you can buy, sewups. You'll notice far better feel, ride and performance simply by using sewups, than you will ever notice using any clincher wheel and any wire-on tyre. Handbuilt sewup rims are redaily available on Ebay for ridiculously cheap prices. I personally favor the old Campy rims (avoid the newer Barcelona model), but Ambrosio Synthesis Durex, various Wolbers and the Mavic GP4 and SSC models were great as well. Avoid the lightweight Mavic GL's, GEL's and any Fiamme's for your size/weight. Among the current production sewup rims, Mavic's Reflex is fine, I personally prefer the FIR (pronounced fear) rims. They had a prototype assymetric drilled sewup 2 seasons ago which I suspect may be in production by now. FIR rims are tough to find in States but worth the search given their superior quality for less money than Mavic.

Among the prebuilt sewup wheels, the Campy Nucleon is a very nice wheel with good hub and assymetric drilled rim. The Bontrager Race XLite is also available as a sewup rim, it's a bit higher priced than Nucleon but also a bit stiffer laterally. I'd call it a toss-up. If you would just take a small leap of faith into sewup world, I promise you will not regret it. Your buddy Flydhest I'm sure could educate you on tire mounting, its far easier than most folks realize. You'll flat less, ride smoother and turn more confidently. You and your Ottrott desreve the best, sewups are just that. Wishing you well, keep on riding good man.

Ride on!

Wednesday, February 16, 2005

BigMac on Wheels

There are a number of different posts here on the topic of Wheels. Of particular note are the "Tubular vs Clincher" & "Big Boy Wheels.

William

>>>>>>>>>>>>>*****<<<<<<<<<<<<<<<<

I think Flydhest here raises an interesting point, is there in fact ANY verticle deflection in a quality built wheel? I'm not a physicist or engineer and thus will not attempt any scientific diatribes based on nonsense thats way beyond my minimal comprehension. I would however suggest that if there were in fact any vertical compression at say road patch area (call it 6:00), would that not require some horizontal expansion at both 3:00 and 9:00 positions? Just a hypothication that I'll leave to far smarter folks than I to debate.

Now from a practical standpoint of personal experience I notice a dramatic difference in feel between certain rims and spoke lacing pattern on front wheels. Sticking with a somewhat apples-apples comp, not deviating to composite rims or spokes and always using sewups only, there is considerable difference in feel between a traditional box section rim and a deeper section aero or "v" rim using identical spokes and spoke lacing. Similarly, there is considerable difference in feel between a radial laced front wheel vs. a traidtional 3x pattern, each wheel using similar rim, hub and spoke guage. Why? Is this a product of vertical compliance? I would suggest it is more likely a case of hf vibration energy dissipation, but that's a non scientific hypothication. Radial lacing and deep section rims use shorter spokes which more efficiently transfer hf frequencies than longer, lower tensioned spokes used in box section, 3x patterns. Does that make any sense? I would further suggest there is little torsional load on front wheel, at least in my expereince even during high speed descents at large lean angles. Why? I do not know scientifically however I tend to run my brake blocks very tight to front rim for better brake response yet do not recall ever experiencing brake block rub under any load on a true rim. Then again I have never spent much time on weight weenie rims like GL280, Fiammes, Assos or similar designs.

Rear wheels are a different beast altogether. These are under tremendous torsional load. I know this because I have experienced brake pad rub on many occasions under heavy sprint or climbing and that's with several mm's of brake block clearence at setup. I would still question the vertical movement hypothication, I have never had brake blocks rub tire side walls for example or a tire rub at forward section of a rear fender indicating a horizontal flex at 3:00 position. Now my real question is why some wheels with poor torsional flex characteristics ride so poorly -- harshly to borrow the phrase used by others. I would offer the original Ksyrium sewup wheel as an example. This wheel felt buzzy and harsh over my normal riding terrain compared to my handbuilt 32/36 3x sewup reference wheels using same sewups at similar measured pressures yet under load it was not difficult to induce enough torsional flex from said Ksyrium to cause brake block rub in rear. I rarely experience similar brake block rub with my 36H 3x handbuilt reference wheel. Was this the product of fat bladed spokes? Massive and deeper section rims? FWIW: I have ridden several examples of this same wheel and each time felt very similar. Among the pre-builts, the Campy Nucleon (now named Neutron) is the smoothest riding sewup wheel ime, and reasonably stiff torsionally with good rider form. The Bontrager Race X-Lite ('02 version sewup) is a bit stiffer torsionally and perhaps a touch less smooth but it too is an excellent DC duty wheelset, ime. I also really like the Hyperon for silky smooth ride and very good torsional stiffness however we're talking a whole different price range which I personally feel is waaaaay beyond reasonable w/o any real gains for anyone short of D1 racers.

I realize this is a deviation from the original posters comments regarding a clincher wheelset which i have no experience with, I just thought Flydhest question regarding vertical rim compliance was an interesting one that seemed to go unaddressed. Then again I did not necessarily answer his hypothication, rather I further muddied the waters with more questions for which I am personally unqualified to answer from a scientific/engineering standpoint.

BTW: Discount ANY and ALL wheel mass claims by most firms, that includes rim mass claims as well. There is no industry standard regarding published wheel masses concerning with or w/o QR's, even when such is specified the claims are often laughable versus actual production examples weighed on properly calibrated scales. Mavic rim weight claims are often 8-10% less than reality, just as an example.

Ride on!

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Zap:

Now you've really got me scratching me head. Are you suggesting a rim diameter, or circumfrence if you prefer, decreases as we tension wheel during build process? This cannot be true, a circle could not shrink in diameter and still be a circle, no? Now if a rim were delivered out of round, yes its shape would change during build-up (to round and true of course) but honestly only the really bad rims are typically delivered out of round to any considerable degree. Now I suppose if you secured a wheel in a stand and pushed very firmly downward on rim its possible to acheive a very infinitesimile amount of vertical compliance but honestly this wreaks of non-real world testing techniques. Certainly a wheel with tyre mounted and inflated to 100-110psi would never realize such a load excepting for event of crash or severe pothole experience. Under 'normal' circumstances, air volume in tire and tire sidewall flex dissipates any vertical loads encountered loooong before any realized vertical wheel compliance, no? I suspect most of the wire-on riders would suffer a rather severe pinch flat long before any vertical wheel compliance would be exhibitted in actual riding experience, heck i'd probably blowout the tire casing of my sewup before such a severe load were encountered to cause such a wheel deflection. Its my understanding that as we tension spokes, the spoke itself elongates, there is in fact no deflection or change in rim circumfrence. To further illustrate this, 14g. spokes require less feel to acheive tension while smaller guage and butted spokes seem to take more patience, at least ime. Just my completely non-scientifically trained viewpoint.

Ride on!

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Zap response:

BigMac,

Now you bring up another interesting dynamic. But to answer your first question, no the rim will not shrink in diameter. It will change shape verticaly or laterally.

Tire pressure puts an incredible amount of pressure on the wheel. So with the wheel just sitting there with 100-140psi, there is a lot of force at play already. More force than with you sitting on the wheel. Now add the additional force of a wheel striking a pot hole with a 180lbs rider.

You are right that it is easier to build a wheel with 14g spokes. Conventional bladed spokes are easy too. It's a bear using revo or ti spokes because these spokes stretch more than straight 14 g spokes. But those thin/stretchy spoked wheels do ride nice

>>>>>>>>>>***<<<<<<<<<<<<<<<<

At your mass, assuming of course you are not hitting every pothole and rock in sight or using these wheels to double for 'cross duty, 32H should be fine if built correctly. Yes Campy 9/10 has worse dish than Shimano, but not THAT much worse...heck they both build with terrible dish. There are better rim choices, but I know plenty of folks bigger than you using same setup getting much better results. BTW: unlike a previous poster, its the drive-side that takes bulk of load, not non-drive due to the terrible dish. I would NEVER send wheels off to be built elsewhere, but that's just me. I have nothing against the mail order guys, its just a local guy who can service any problems that may arise such as in your case is a far better choice. Joe does build fine wheels but w/o peer? Not hardly. He wasn't even the best in town when he was shlepping his wares in Bay Area several years back...no offense but there are LOTS of skilled wheelsmiths throughout US, simply no reason to send mailorder. If you do live near Joe, then he would be a wonderful choice for a fine wheel. otherwise call around to local bike clubs, there should be 1 or 2 local wheelsmiths to serve your needs.

To deal with the problems you are experiencing, much more info is needed. You do not mention spoke breakage, only trueing, nipple and rim eyelet issues, true?. Are these alloy nipples by chance? If so, this is your primary culprit, ALWAYS use brass in rear. Alloy nipples loosen, stretch, strip, corrode, sheer..... What is respective lacing l/r(drive, non-drive). What spoke choice? Same throughout or differential l/r? If you rebuild wheel w/14g straight laced 3x on drive and butted 14g laced 2x on left using only brass nipples and properly tensioned, you should eliminate any problems you are experiencing. Tension should be rechecked at first 100-200 miles, otherwise they should be fine for at least 2500 miles before any trueing issues.

If you are interested in the ultimate bomb-proof setup, get a Bontrager Aurora OSB rim in rear. Assymetrically drilled, MUCH better quality than the Velocity/Ritchey rim at a bargain $39USD retail. These are available in 32 and 36H drillings. Choose 32H to retain existing hub, same lacing, spoke guage and brass nipples as above. You will however have a noticably stiffer wheel torsionally, in fact the left spoke tension will be nearly identical to right side. Good luck.

Ride on!

>>>>>>>>>>>>>>*****<<<<<<<<<<<<<

Hoover:

Using an assymetric drilled rear rim like the Velocity is certainly a better choice for the King hub, but using a C/S hub with assymetric rear rim is even better yet. The "Jerk" is spot on with his assessment of King hubs, they are WAAAAAY overpriced and poorly designed. Not to sound crass but I believe the kids would call these poser hubs, no?

You are far better off using an Ultegra hub, your wallet will remain considerably more plentiful which in my book is always a fine thing. If you absolutely, positively must spend money on 'bike jewelery' hubs, at least buy well engineered ones. Sounds like you are running a Shimano drivetrain thus you may choose Phil Wood hubs, they do not offer a Campy spline mode and. Yes they are stronger and better engineered than anything Shimano with a flange design that will result in better spoke tension balance. Honestly, unless you are really big and very hard on wheels, this is an excercise in overindulgence. The White Ind hubs are also superb, sharing nearly identical flange design as Phil, they are however even pricier though a few grams lighter as well -- if you believe lightweight hubs contribute anything on an unsuspended bicycle.

For rims, get to your local Trek/Lemond shop and order a set of Bontrager rims. The Aurora is name of 20mm width clincher rim. It is available assymetric drilled, just like the Velocity, only its uses a FAAAAR more reliable MIG welded joint and is $20-30 less $$! $39 retail for the best clincher rim ever...if only they offered a sewup rim of same design.

Ride on!

>>>>>>>>>>>>>>*****<<<<<<<<<<<<<

Tubular vs Clincher:

I do not know if there has been an emperical study performed that would prove sewups have lower rolling resistance than wire-on, but it is a fact. Speak with engineers at Continental, who produce high quality versions of each design used by pro's worldwide, they will tell you sewups are lower rolling resistance, at least in theory. Places where ultimate speed is the only criteria, velodrome racing for example, only use sewups. It does have something to do with casing design and friction losses due to the loose tube, this is one of the supposed benefits of the new tubeless clinchers. For practical terms, anyone around this forum, including yours truly, is not going to be even fractionally faster based on tire design choice, at least in straightline racing.

If you were however to include high speed descents in your riding regimen, I do believe the sewups will be faster for most aggressive riders due to much improved handling response, feel and performance(grip). I also suspect any triathletes competing over most long courses could gain considerable time using faster rolling sewups as used by every elite triathalete and professional road racer over long TT events.

For most stage events, pro teams generally prefer sewups for 2 reasons, performance and servicability. In reality, the field is nearly even at this years TdF due primarily to Michelin being the largest professional sponsor. All Michelin support contracts REQUIRE teams to use clinchers a minimum of 50% of total miles, some teams much higher. Michelin does not produce sewups however teams are allowed to contract for mock-up sewups that employ cosmetic features of Michelin clinchers, namely logos and tread colors. Yes, pinch-flat prevention, low rolling resistance, handling performance are all important factors but perhaps the biggest factor in choosing sewups among pro teams is ability of wheel to continue to be ridden when flatted while race support attempts to get to rider. If a puncture occurs with a clincher, the wheel can rarely be ridden safely thus rider often must wait helplessly at roadside till a race support vehicle can get to him for assistance. This can mean minutes, not seconds and has often occurred thus far in this years Tour.

On this very forum this topic has often been rehashed with the identical arguments. There are in fact fans in both camps, perhaps a few may even convert to clinchers with soon introduction of Mavic-Michelin road tubeless design. I would not dismiss either design w/o a full hands-on demo of each under your normal riding conditions. The difference in feel is considerable, as is installation and servicabilty. Use whatever works and feels best to you and your needs. Heck whatever gets people on their bikes more often is ALWAYS the best choice. Debating rolling resistance is synonymous with debating whether smooth or file tread offers better performance...it just don't matter.

Ride on!

>>>>>>>>>>>>>>>*****<<<<<<<<<<<<<<

Big Boy Wheels:

William:

I am not your size and probably considerably older and less skilled. I am however a very muscular 6'2" 230lbs. My first suggestion would be to avoid Mavic K's, with all due respect to the gentleman who suggested them. K's are simply not designed for anyone our size, they will self-destruct in under 1000 miles. The cracking eyelets have been a long standing issue with many alloy rims using SS eyelets, the Mavic K's seem to suffer this more than most but honestly most similarly designed rims can have these problems and in many instances it does not effect structural integrity of wheel. The K's however lack torsional stiffness of a big guy wheel, I can easily produce enough flex to cause rear brake pad rub during in saddle climbing, out of saddle sprints are far worse often accompanied by loud popping, creaking and several spoke failures. Mind you, my expiences are with the sewup version but in most cases these are torsionally stiffer than the wire-on versions.

For prebuilt wheels, I'd follow Sr Jerk's suggestion of Bontrager Race X-Lite sewup. Great wheel, low dish, sewup, great customer support. The Campy Nucleon (aka Neutron) sewup olso features assyemtric rim/reduced dish design however its slightly lower torsional stiffness and customer support pales in comparison to Trek(Bontrager's parent). Sounds like you may be a wire-on/clincher guy, I won't hold that against you but would suggest sewups for best performance, handling, feel and strength. For clincher prebuilts, I'd suggest the Campy Eurus followed by Bontrager Race Lite. The Eurus has worderful torsional stiffness that beats out even the great Race X-Lite sewups. The Race-Lite clincher is lower priced clincher only version of X-Lite offering same performance and 2 extra rear spokes plus Trek support.

If you would like to use custom handbuilt wheels, the options are fewer but the results will be significantly less $$ and potentially stronger rear wheels. Unfortunately, there is not a sufficiently strong sewup rim readily imported in 'States thus I would again reiterate the suggestion for the Race X-Lite prebuilt wheelset as my top choice for sewup wheels. For handbuilt clinchers, the Bontrager Aurora assymetric rim is the best clincher rim available anywhere. Nice alloy rim, welded joint and assyemtric 32H drilling for reduced dish. Lace'em up with Campy or Shimano hubs and they should need very minimal servicing or care for 5k miles at the very least. If you needed any extra assurance, Phil Wood (Shimano spline only) or White Ind (Campy or Shimano spline) hubs are also available in several drilling patterns and feature flange designs which will further reduce spoke tension imbalances in rear wheels. Mind you these are considerably more $$ than C/S hubs and probably overkill for your needs (highly recommended for loaded touring uses however) but it is an option. Avoid King, Edco and several other "lightweight" hubs, they actually increase wheel dish due to poor flange designs, bad news for big guys like you and I. I would also suggest a straight 14g driveside spoke 3x lacing -- a very good friend of mine similar in size and fitness to you(he recently retired from NFL as TE) used DT's butted 13/14g spokes on driveside and his wheels are absolutely bombproof. For leftside (non-drive) rear use a butted 14/15g spoke with 2x lacing, the spoke length and tension left-right will be almost completely equal which results in a VERY strong, durable and torsionally stiff rear wheel. Best of luck.

Ride on!

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Big Boy Wheels cont...

William:

I'm not really looking to "convince" you to change your ways, I merely suggest you try a quality sewup and let the experience do the convincing. During my frequent travels i often ride loaner bikes and I can assure you the minute I take the initial pedal stroke and just the slightest nudge on the bars, I can identify whether the bike I am riding has clinchers or sewups. If its clinchers I just do not enjoy the experience of riding nearly as much.

I would like to correct a misnomer you seemed to have acquired regarding sewups, clinchers are FAR more prone to roll-off than a sewup. Pro's still use sewups predominantly, by a very wide margin. In fact, many teams and vendors go to great lengths to disguise a sewup to appear like the sponsors' clincher tire for marketing-sponsorship reasons. Why are sewups the pro's tire of choice? Reduced rolling resistance, ride quality and cornering ability are important but somewhat minor factors from race support standpoint. The primary reason is that when a clincher punctures, it flats in under 30 seconds and is basically unrideable. If one was to be descending at high speeds, a puncture could very likely cause a roll-off and very severe crash. Conversely, short of a blown casing, a sewup puncture will cause a very slow leak allowing the rider to continue racing for several minutes while race support vehicle can provide wheel replacement assistance. This alone can save 2 or more minutes for a single rider. A sewup is in fact glued to the rim but that is actually a supplemental retention system. The primary retention is the tires inflation pressure. Unlike a wire-on where the higher the psi, the greater the pressure on bead and casing to prevent dismount, a sewup actually increases it grip on rim as psi increases.

If you're worried about glue softening due to brake induced heat build-up, the easiest response is to improve your descending skills such that you will not need to brake as often. You should basically never use a rim brake enough to cause excessive heat build up in racing or hard training conditions, this is only a concern for loaded touring bike riders. Not good enough? If front brake begins to feel soft or fade due to said heat build up, use a H2O bottle and apply 2-3 light, steady squirts at backside of forkcrown.

Joseba's roll-off was in fact a sewup however it is my understanding from 2 of the now former Once mechanics that the tire in question had flatted prior to the roll-off. This is based on some unscientific video review but primarily a close examination of the tire in question which had a severely punctured casing when examined. Interestingly (or frighteningly as it were), Joseba does not recall much of the actual events leading to his crash.

Enough about sewups v clinchers, the modern clincher is infinitely better than the clinchers of old and if you're happy with'em, no problem. Find a local wheelsmith and have them lace up a set using the Bontrager assyemtric rim in rear, you should have trouble free wheels for many thousands of miles. I would encourage you to use a local wheelsmith only. I would personally never recommend any mail order/online wheelsmith to anyone, but for someone your size it would be even more critical. Big guys like you are hard on all wheels, no matter the quality of build. An occasional tweak or trueing is to be expected, many local wheelsmiths will either not touch a wheel they did not build or will charge a very high fee for any adjustments and offer no warranty for said work. If its a good local wheelsmith, they will provide spoke repairs/replacements at no charge along with any adjustments on wheels they have originally built. Check with local cycling clubs for the referrals, there is usually 1 or 2 local wheelsmiths who's name and reputation exceeds all others. If you are located in SF BayArea, the best wheelsmith is in Berkeley, I'll be happy to give you his name if you require.

Ride on!

BigMac on Chain lube

Originally posted on the Serotta Forum.

William

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The mineral spirits just thin the oil, allowing it to better penetrate bushings. This has been a standard diy lube for decades. Used sparingly, as is true with almost all chain lubes, its effective and durable for dry road usage. If used in dusty or dirty conditions, the results are typically pretty ugly. While the oil will not wash off in rain, it will attract debris, dust, etc.

I have used White Lightening with rather poor results. Yes chains appear clean but chain wear is generally poor due to this products poor lubrication/friction coefficient. The Finshline Teflon Plus is better than White Lightening but requires frequent applications for reasonable results.

I've used Dumonde chain lubes for several years on various chain driven motorcycles. I've also used the Dumonde 2 cycle oil on snowmobiles with excellent results. I've yet to use a product of thiers that has not been equal or better than other products on market. I was among the 1st to beta test the bicycle chain lube, it is a bit different formulation from the motorcycle chain lube, primarily because I had been discussing the usage of the motorcycle chainlube on my bicycle, thus they offered for me to demo the bike chain lube. In my experience, this is the best chainlube available. I've never used ProLink but friends that have, later switched to Dumonde Tech with better results for wear, longer lubrication intervals and cleaner chains. Boeshield T9 is a great steel preservative as was its original design by Boeing, it however was not intended to be a lube and in my opinion should not be used as such.

Great care should be used when applying Dumonde. The original and Lite versions are in fact identical, the lite is simply a 6:1 dilute solution of original. If you like to slather lots of lube on, use the Lite and use 1/4 what you think is correct. If you use original, 4-5 drops is sufficient for entire chain. If you use more than that, you risk chain collecting dust, dirt, etc. While most "dry" lubes are teflon or some polymer in suspension, Dumonde is actually a liquid polymer that vulcanizes under pressure. The liquid penetrates bushings and under load it becomes a plastic-like substance that acts as dry lubricant. What liquid does not penetrate bushings must be wiped off or it will remain a liquid which in time and usage will attract dust, etc. This stuff should also be used in a well ventilated area, while some may find the odorous liquid not overly objectionable, something that pungent cannot be good for olfactory senses.

If you do choose the Dumonde Tech lube, I do beleive most will find it a very fine product, if used properly. Always apply initially to a clean and dry chain, yes new factory fresh chains must be cleaned as well. Most importantly, whatever you think is the correct amount, use 25% or less of that amount and you'll still probably be applying too much. For many the Lite is easier application in that its harder to apply too much. For owners of chain driven motorbikes, both primary and output as applicable, the Dumonde motorcycle chain lube is really good stuff, especially for off-road/motocross duty.

Ride on!

BigMac on Rivendell Redwoods & other Big Guy Stuff

Bigmac responding to Brons2, a 6' 7" rider looking for help on getting the right frame for his size.

William

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One thing you need to be aware of with Rivendell sizing is that frame sizes are listed by measuring ST from center BB-top of TT @ seatlug. Most frames, including Serotta are measure c-c thus a 68cm Riv is roughly 66.5cm Serotta. Honestly, ST length is the least important frame dimension, imo, check out TT length, STA(or setback), cs length and front center for proper fit. Redwood (big Rambulliet) is a very nicely constructed frame and relatively stoudt for a production model. If you're riding is limited to Texas, especially the Dallas area and you have even a marginally smooth cadence, i suspect the Redwood is about the best value in a quality frame you will find. I would have just 2 reservations if I were in your shoes; the quill stem and frame durability.

You are obviously a very large rider, considerably bigger than your average rider and if you have large upper body build you likely generate excessive torque on bars/stem. I am 30lbs your junior, albeit very large and powerful upper body build, and I have bent my share of forged alloy stems. I love the threadless stems and particularly a custom fillet brazed steel stem, they are far less prone to flex/bending than most production gear, particularly the current plethora or weight weenie sub 200g stems which should be avoided by anybody your size (actually they should be avoided by everybody but let's not go there right now). The Redwood uses a threaded fork-quill stem setup, it may be fine for your size if you are gentle on torqueing bars and you avoid stem extensions beyond 11cm max. The other alternative is Riv sells a Nitto-produced lugged steel stem which is apparently extremely stiff and strong, although extraordinarily pricey to boot (>$200). Salsa also offers a TIG welded cr-mo stem but it has minimal quill length and is very soft flexing, ime. Of course Serotta and most other builders are now employing threadless setups in which case I would suggest you purchase a custom filet brazed steel stem of any necessary length, be sure builder of said stem is aware of your size, strength and mass.

The frame durability may be a moot point if you are remotely smooth pedaller and ride in relative flatlands of Texas. If you intend to ride competitively, likely sprinting would be your strength or travel with bike for riding in more vertically challenging terrain, I suspect the Redwood is insufficiently stout in bottom-end. I have personally ridden a 64cm Rambu and honestly felt the lateral movement at BB was sufficient enough while climbing that frame would have failed within couple thousand miles. This however does not make it a bad choice for you riding the flatlands, I could have spun all day on flat ground and enjoyed the frames ability to smooth weathered roadways, its just not a suitable climbing or sprinting frame for bigger, heavier riders. Frame builders must make certain choices for production bikes. If one were to build a production frame intended for a rider your size performing out of saddle sprints or hard climbs, the poor "diminutive average" rider fitting same size frame, weighing 200lbs would likely feel beat up, unable to produce a desirable amount of frame flex. I suspect the 68cm Riv production frames were built around former Riv employee Bhima who stood at least 6'6" but weighed maybe 185lbs...soaked through in the rain If you can find a demo Redwood/Rambu to take for a 30-40 minute spin, that would be an invaluable experience, otherwise frankly anything short of a full custom frame is a crapshoot. FWIW: Serotta makes great bigboy frames, probably the best anywhere, if you can afford it they are your safest choice.

Ride on

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Jim:

My apologies for my previous error in thinking you were located in or around Dallas. I had read the Richardson, Tx shops mentioned and errantly assumed you were located in that area. I do know the distance to Austin is substantial, my inlaws are currently in Richardson and my wife grew up in Plano.

Good to hear you got a fine deal on a Cannondale, if it fits well that is a very good choice for someone of your size. i do believe C'dale has discontinued production of such large frames, you buying an NOS model should have no negative impact, in fact I would say you are a very fortunate fellow.

The wheel issue is fairly common one for folks of all sizes, at least if wheel is poorly built as I suspect. The spokes should have been pretensioned during build -- brought to full tension and trued, then backed off and retensioned and trued -- which I suspect was not done. Your ride simply stretched the spokes as would have occurred with a properly constructed wheel. It does not sound as if significant damage was done to rim so in truth I suspect the wheel could be properly retrued using existing wheel components and you'll be good to go...up to a point. These wheels are really a compromise for your specific needs that will likely require considerable maintainence, more than I would consider acceptable: retrue every 800-1k miles and periodic replacement of individual driveside rear spokes due to breakage. Solutions? Bontrager Aurora OSB rear rim. Available for $39 at any Trek dealer, some may even stock them, others could order with maybe 1 week wait. This is hands down the best available clincher rim on market -- welded joint, assymetric offset drilling, minimal decals/logos -- and its roughly 1/2 the cost of Open Pro/CXP33. Use DT straight 14 guage spokes laced 3x on driveside, DT 14g (you could opt for butted 14/15/14 but honestly that's a few cents more per spoke for absolutely zero benefit) laced 2x on left side w/Bontrager rim, the result will be nearly identical spoke length and tension on each side which equals a very torsionally strong and durable rear wheel. This wheel should be stronger torsionally than a traditional 36H rim of similar mass laced with similar spokes. The next step up would be a Bontrager Fairlane(or Maverick as they have recently changed model names but design is unchanged) OSB 36H rear rim. A bit wider and heavier rim (525g or thereabouts), still welded at joint and assymetric drilled but would require a new 36H rear hub to replace your current 32H unit. Personally, I would opt for the 32H setup, however you will need a much more skilled wheelsmith to perform the build than the one who laced the current setup. Speak to members of local cycling clubs for good recommendations of skilled local wheelsmith's (do NOT go mailorder!), I'm sure you will find at least one in a city like Austin.

Your pedal issues could be a bit more troublesome. The best solution would be to have a friend observe you from behind as you pedal at a normal cadence. Alternatively, use a video camera set at hs shutter on a tripod placed again just behind bicycle just left or right of rear wheel with bike on a stationary trainer. Be sure you are sufficiently stretched and warmed up, pedalling in a normal cadence. Now my suspicion is that you are pronating (or supinating as I forget which is which) wherein the ankle is rolling inward at bottom of stroke. This is a biomechanical issue that could be related to saddle height and/or fitness, strength or physiological issues. If your observer or video camera shows lateral ankle movement, this is in fact your problem, not the pedals per say. Solutions? Lowering saddle a bit can help, generally as your fitness improves, some stretching/yoga is highly recommended as well, you will again want to elevate your saddle for more efficient pedalling stroke. You may also need to experiment with orthotics or arch supports. I would recommend you avoid using running shoes while riding, the elevated foam midsoles may exacerbate your problems. If you are not using toe clips with your platform pedals (or even if you are) try a pair of PowerStraps and use the thinnest soled shoes you have...I prefer Mephisto sandals when I use platform pedals -- I find BMX style platforms (MKS brand) with the stubby knubbs hold my feet pretty well -- using PowerStraps for powering up the hills. If you do choose to convert to a clipless style pedal system with requisite shoes, be sure you identify whether an orthodic type device will be required as this will have significant impact on shoe fit choices. Clipless pedals are generally considerably higher q and stackheight (distance from pedal axle center to shoe platform) than platform pedals, with one exception; the Time brand road pedals. If you truly do require high Q pedals, avoid Time and probably look at Speedplay. They offer a model Zero that allows you to limit float rotation (could be very beneficial if you have lots of lateral movement) but they do have a very disconected feel which takes some acclimating and are very wide Q. Look also offers a model with an adjustable q that can be very wide if needed, the balance of pedals are all pretty similar (moderately wide q compared to traditional quill or platform pedals). The last solution could be to add a 1-2mm stainless washer between pedal and crank arm, this however should be a very last case solution given your size/weight to avoid bending of pedal axle. Best of luck to you.

Ride on!

Tuesday, February 15, 2005

Big Boy Cross Bikes

BigMac responds to a question about "off-the-peg" cross frames for big boys. Do they exist?

William

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BigMac :

Are you not the young lad in the 260lb range? If so, why would you even consider off-the-peg frame? I do not know your riding experience but my personal experience suggests you are considerably too large and strong for ANY off-the-peg frame. At my relatively diminutive 230lbs, I have broken numerous frames, most custom built with my size/strength in mind. I once went on a demo ride using a team racing support bike that had just had the plastic wrap removed and been assembled by the mechanics yet the right cs snapped on the 3rd or 4th out of saddle stroke up a very mild incline, less than 5km's into ride...14 stitches later to my right shin I knew I shouldn't have ridden such a flyweight frame. I'm not suggesting you'll have similar results with all off-the-peg frames but I am suggesting there is likely not a single off-the-peg frame that will provide even 5k miles of service to someone your size w/o some structural failure. You can pay a few extra bucks now for a properly designed and sized frame or pay similar amount for the same after you've wasted $1000 on the off-the-peg frame that fails...and hopefully does not cause injury during failure.

As for sizing, I would focus more on ST angle and TT length rather than "frame size" which usually reflects ST length, a meaningless dimension imo. There is also a broad differentiation in defining "cyclo-cross" geometry. Many of the younger (mostly mtb influenced) builders consider a 'cross bike as an mtb w/700c wheels witnessed by high bb's, tall and slack front ends and sloping TT's. The more traditional approach is essentially a 70's racing bike geometry with slightly longer stays for mud clearence and canti braze-ons. A typical example of former would be from IF or Brent Steelman. I know folks who use the Rivendell Atlantis for trail riding but unfortunately it's BB/chainstay design makes it a poor 'cross bike -- a major gaffe by Grant imo is widely splayed round cs's that prohibit usage of low q double cranks.

I would suggest you contact Tom Oswald who is located in relatively nearby western PA. He loves racing 'cross, builds nice lugged steel bikes w/o the foo-foo details that don't matter when you're bombing down narrow single track with rocks and mud pounding the underside of frame. I believe his frame pricing is similar to production frames like Atlantis. He can build a frame that will hold up under your considerable load -- at least longer than any production bike -- and hopefully the wait will not be excessive. Of course you could get a Legend 'cross bike as they are once again building canti-bossed frames but I suspect that is well beyond your intended budget.

Ride on!

BigMac on Steel

Metallurgy and cycling, the party animal topic of the cycling world!! Well, not quite but it's a facinating subject. I will include other posts from very knowledgable people here. This turns into a very technical thread thanks to Germanboxers and MadRocketSci. Great reading on Metallurgy and cycling.

William
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Posted by William:

Frames of today vs Yesteryear...
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What do you think of the thought that the thinner walled tubes of many frames made today just won’t stand the test of time over the long run? They may be able to be made stiffer by OS-ing the tube diameter, but what about longevity? Is the quest for lighter & stiffer frames sacrificing the longevity of frame performance? One would think that thicker tube sets would last longer. Someone mentioned one manufacturer saying that their frames had an average life of 5 years. I’ve heard people say replace every couple of years. If this is true, then it appears that some manufacturers are moving to disposable products like so much of what graces the shelves of stores today. Is this just a by-product of consumer demand? Technological advances? Everyone wanting lighter bikes? Or is it possible that “planned obsolescence” has reared its ugly head once again?


Just the kind of dribbling thoughts that flow through William’s mind as the caffeine is starting to kick in early in the morning.

William

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Posted by dbrk:

I remember in Cyclesport the chairman of Cinelli saying that their new aluminum frames _should not_ be ridden everyday or for more than a year or two, anymore than a Ferrari should be taken out on the road for everyday driving. The modern race bike as a specific, limited tool for a job is the obvious ratonale. Bikes are more "fragile" because roads and wheels are better but they can tolerate less. It's a throw-away world, after all. Why build something to last?

Most of my bikes will undoubtedly last far longer than I will at this point. My '72 Mondia Special, purchased new when I was a lad, still rides beautifully and I have three or four bikes made in the last five years of NOS 531 and they ride as well or better than anything else I own, imo. Still, I am not averse to modernity or to trying on some zooty stuff. The Hampsten Z1 has been a particular pleasure though I think I shall never get used to the difference between carbon and metal (my take is that carbon quiets the road as soon as possible and steel lets it diffuse over the whole of the frame, hence steel's soothing tuning fork-like quality, it's liveliness.)

But more honestly, I'd bet that the vast majority of aluminum, carbon, and ultra thin steel bikes last years and years and without much, if any, deteriorization in the quality of their ride. Unless the welds are corrupt or the glue comes undone or other reasons that would equally apply to more stalwart tubing, they will neither fall apart nor change. Of course, I am adamantly of the view that the quality of a ride does not change over the years due to metal/material changes.

Most of my favorite bikes will be no more obsolete tomorrow then they were the day I bought them just like most modern bikes will ride no worse tomorrow then they already do today.

dbrk
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Posted by OldDog:

I think all aluminum frames have a limited life (short) when used on a regular basis, and steel frames will last as expected for a very long time due to the longevity of the material. I don't know for sure but would expect todays steels to have better inherent anti-corosive properties and with coatings such as Frame Saver, should remain rust free at least as long as the tubesets back in the day, that is the the thinner tubes should not rust through. (any frame builders can chime in here) It will be interesting to see 10 - 15 years down the road if todays carbon layups are still going strong, with regular riding, barring crashes.
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Posted by BigMac:

William:

Your inquiry does not identify a single material but I assume you were primarily inquiring about steel frames as the alternatives have only been primarily produced in bike frames for 20-odd years. As for the "other" materials, the various aluminum alloy frames and plastics will have very finite service cycles, perhaps assisted by OS tubing and improved construction techniques but certainly not a 10+ year service life if used on a regular basis -- say 6k miles/yr. I suspect Ti frames, especially something with shapely OS tubes like a Legend, may in fact still provide servicable duty to your grandchildren...if they are so inclined to ride such a "dinosaur-era" contraption .

Specific to steel, yes tubes are drawn thinner but larger diameter than in 70's and prior to. Be aware however that vendors have made quantum leaps in steel alloys. The defacto 70's steel was Reynolds 531, a manganese-molybedenum alloy with tensile strength of maybe 125-130ksi. In mid-late 70's, Reynolds introduced 753, a specially heat-treated 531 that increased tensile strength to a claimed 175ksi. Now OS diameter tubing for bicycles was still a few years away but this increase in tensile strength allowed very thin walled tubing. For example a butted 531DT had typical wall thickness of 1.0/0.7/1.0mm or a lighter weight 0.9/0.6/0.9mm. The 753 was available as thin as 0.7/0.4/0.7mm. All being made of steel, the density is same but obviously far less material was required to acheive similar strength/safety/performance with 753 thus a lighter frame resulted. The thinner wall tubing was more prone to denting and rust damage because there was so much less material. 753 was available in very limited quantities and only to select builders who had to be certifed by Reynolds before they could purchase the tubes.

If we leap forward to today, 175ksi tubes are commonplace, in fact I believe every steel tubing vendor has at least 1 tubeset in their stable claiming over 200ksi! The belly of butted tubes is not really any thinner as most are unable to draw tubing thinner than 0.4mm (Columbus claims 0.385mm in at least 2 tubesets) but the ends are often thinner guage than even that legendary 753 tube. More importantly, the larger diameter tubes offer considerably higher torsional stiffness. Even in 753 frame construction, a 531 DT or specially drawn thicker guage 753 DT would often be employed in larger frames, that was an era of 28mm OD DT's. Today, a tube of similar tensile strength may be 32mmOD at HT and 35mmOD at BB offering higher torsional stiffness but can be lighter guage thus no added mass.

Back to your original inquiry, I do believe the "modern" steel frames with lighter guage OS tubes are certainly more prone to denting, they are also more susceptable to rust failure because the thinner guage has removed much of that 'margin of safety' the heavy guage allowed. These are only concerns to those who may neglect and/or abuse their frames. Don't bash around you frame, treat inside of tubes every 5 years or so with Boeshield..."problem" solved. I would personally be a bit reticent about the longterm durability of TIG'd steel frames. I know some builders consider this somewhat over cautious but somehow these super-thin walled tubes being melted together causes some consternation with 20 year service cycles. With all of the above said, I have personally owned MANY lugged steel frames during the past 35 years and have never had one last more than 25k miles w/o some failure. Yes they are in most cases easily repaired, but never-the-less that is my experience.

Ride on!

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Posted by zap:

This is a complicated question.

1-Materials (steel, carbon, al) are superior today than what was available even 5 years ago.

2-Designs are more sophisticated to better withstand forces and fatigue.

3-Build quality. This is still the most important aspect to longevity.

Metal tubing is thinner today, but it's oversized and shapped. Oversizing tubes increase strength quite a bit. Double the diameter of a tube, strength goes up 4x, if wall thickness stays the same.

But wall thickness is a problem. It's easy to dent thin steel and al tubes, so crash worthiness isn't what it used to be. Ti will hold up better in this regard.

I think most people will sell frames before useful life expires.

By the way, high tech even allows todays Ferrari's to be driven every day.

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Posted by MadRocketSci:

maybe a metallurgist can say for sure, but, i don't think that yield strength and fatigue resistance are the same thing. more material = more margin for microcracks (are these called "dislocations"?) that develop over time...

disclaimer: took this class a long time ago and my engineering materials book is at my parent's house so correct me if i'm wrong....

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Posted by Andreu:

we live in a throw away society. Even if it is not true, the notion of being able to change your belongings after 5 years because the manufacturers have built in obsolescence is appealing to alot of people.
A

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Posted by climb1742:

i may be superficial but i honestly doubt in ten years i'll want to ride the bikes i'm riding now. there may be one or two, but as zap said, i'll tire of them before they fatigue. sorry, here i guess i'm part of the problem, not part of the solution.

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Posted by Germanboxers:

Quote:
Originally Posted by MadRocketSci
maybe a metallurgist can say for sure, but, i don't think that yield strength and fatigue resistance are the same thing. more material = more margin for microcracks (are these called "dislocations"?) that develop over time...

disclaimer: took this class a long time ago and my engineering materials book is at my parent's house so correct me if i'm wrong....



Yield strength and fatigue resistance are two very different things and so very unfortunate for Aluminum that they are. This is the primary reason many Al-tubed frames have massive diameter tubes...fatigue resistance. With steel there is a fatigue limit, a stress level that if not exceeded will NOT contribute to the eventual failure of the material through repeated loadings. Aluminum does not have this limit. With Aluminum every single stress applied eventually contributes to the failure of the material. Small loads contribute a little, big loads much more, but eventually it will fail if ridden enough.

The "more material = more margin for microcracks" is... how can I say... WRONG! MadRocketSci, I think you've confused a couple different metallurgy terms. "Microcracks" may be used sometimes in the place of "stress risers", but it's pretty uncommonly used among Mets. There is no reason to believe that more material = more margin for stress risers, certainly not the small additional material we are talking about. Stress risers are often created by extreme geometries (we're not talking "crit geo" versus touring geo here) and/or bad assembly/machining, etc.

Dislocations are missing planes of atoms within the crystal structure of the metal. They are highly valuable to the metallurgist for without them, there is little to do to control the strength of materials. Dislocations cause a stress field within the crystal (for just a few atomic spacings). As external stresses are applied and slip begins, dislocations move. To strengthen (raise the yield strength) of a material, we introduce other stress fields by alloying (makes crystal bulge out just a little), precipitates (a small, coherent with the crystal "rock" will create a stress field), reducing grain size (grain boundaries create stress fields), etc. These stress fields react with and impede the movement of dislocations. By controlling these, we control the strength of the material.

Sorry for going off on a tangent, but as I've said before on this board, I've so few things I really know that when the topic comes up I tend to go off. I'm a metalllurgical engineer by training, but I play a mechanical engineer in "Days of our Steel Rolling Lives". Have a great night everyone!

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Posted by MadRocketSci:

Thanks Germanboxers for the clarifications!

Like I said, it's been a LONG time...materials engineering was a 2-unit class in the aerospace curriculum, and a crappy class at that...the prof made us read some soft cover orange book called "Engineering Materials I" and then regurgitate it on the final. Now that it's barely coming back to me, I did use the wrong term. Dislocations are those things that you're trying to move around when you cold roll something to increase yield strength, right?

The picture I have in the brain is little cracks in steel propagating...i recall that the stress at the tip of a crack is 3x larger than without the crack. The crack slowly grows as stress is applied until the material fails. Is the assumption that more material gives it more room to grow before failure occurs wrong?

I guess the point I was trying to make was that everybody equates strength of the material with fatigue resistance. I'm still not sure this is the case. If you have a steel tube that has higher yield strength but less wall diameter than another steel tube, does it lower or roughly the same fatigue resistance?

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Posted by Germanboxers:

>>>Quote:
Originally Posted by MadRocketSci

Dislocations are those things that you're trying to move around when you cold roll something to increase yield strength, right?>>>



Correct! Just as alloying elements, grain boundaries, etc have stress fields that interact with and impede dislocations, dislocations interact with and impede other dislocations. Cold rolling introduces massive quantities of dislocations and dramatically strengthens the material. It also makes it very brittle.


>>Quote:
Originally Posted by MadRocketSci

The picture I have in the brain is little cracks in steel propagating...i recall that the stress at the tip of a crack is 3x larger than without the crack. The crack slowly grows as stress is applied until the material fails. Is the assumption that more material gives it more room to grow before failure occurs wrong?>>>



Correct. I must have misunderstood you. I thought you were suggesting that more material = higher probability for stress risers and the microcracks they form. Yes, more material buys you some time, I suppose.


>>Quote:
Originally Posted by MadRocketSci

I guess the point I was trying to make was that everybody equates strength of the material with fatigue resistance. I'm still not sure this is the case.>>



There are many factors to consider. Most associate the strength of the material with yield strength. This is, of course, different from stiffness. In fact, stiffness is roughly the same for all grades of steel from soft/ductile steels to the strongest more brittle steels. Stiffness relates to the elastic portion of the stress/strain curve, whereas yield strength relates to the stress at which the material begins to plastically deform.


>>Quote:
Originally Posted by MadRocketSci

If you have a steel tube that has higher yield strength but less wall diameter than another steel tube, does it lower or roughly the same fatigue resistance?>>



I wish I could answer this intelligently, but my education/experience in this area is over 15 years removed. I would guess though, in the context of bicycles frames, that you can't really frame (no pun intended) the question in this way. It's probably more appropriate to discuss fatigue by discussing the strains, rather than the stresses. A larger diameter tube is stiffer and would therefore deflect/strain less. I would imagine that this is one reason Al frames are usually made with large dia tubing, usually much larger than what would be needed to make a reasonably stiff frame. It's likely a safety margin that also allows for greater life of the frame since the strains are less. Is the move toward smaller diameter tubing with Al frames the reason some say they are only good for x-years now? It probably plays a role.

With steel, the limit is probably never exceeded with normal riding/racing unless an accident occurs. Even then, you still have a great deal of life left in most cases. I would bet that most steel frame designers don't give too much attention to fatigue failures? Maybe someone with more knowledge (paging all you frame-makers of fame) could answer this question?

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Posted by Andreu:

Out of interest and further along the tangent..
------------------------------------------------------------------------
how homogenous is metal....does it have a grain (like wood)? I presume the atoms are lined up in a certain way and can be manipulated to line up through processing? How do they make tubes for bikes (and where are the biggest stresses introduced into the tube)?
Thanks for info.
A
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Posted by Germanboxers:

>>Quote:
Originally Posted by Andreu

how homogenous is metal....does it have a grain (like wood)? I presume the atoms are lined up in a certain way and can be manipulated to line up through processing? How do they make tubes for bikes (and where are the biggest stresses introduced into the tube)?>>



Most metals have a "texture", an anisotropy. In otherwords, the strength and ductility in one direction is somewhat different from another direction. Most of this is due to the forming processes used, not an intrinsic property of the material. They do not have a grain in the sense that wood does, unless it is cold worked and not fully annealed. We speak of "grains" in that each grain is a collection of crystals that are oriented in a certain way. Adjacent grains are oriented differently. All, however, have the same crystal structure.

For most steel alloys, the atoms are arranged in what is called a body-centered-cubic structure (imagine a cube with an 1/8 Fe atom at each corner and another stuffed in the middle of the cube). There are some grades of stainless (high Ni varieties) that are called "Austenitic Stainless" that are arranged in a face-centered-cubic structure (imagine a cube with an 1/8 Fe atom at each corner and 1/2 Fe atom on each face of the cube).

I believe that tubes for bicycles frames are seamless tubes, basically solid steel rods that are pierced and then drawn to make the tube?? If they are indeed seamless tubes, then the stresses are fairly uniform. Of course joined ends are subject to higher stresses. I would love to see bicycle tubes drawn...anyone have access for a field trip???!!!

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Posted by William:

Great feedback everyone!!! Just the kind of information I was hoping the fine group of Serottaians here would contribute.

I got to thinking about it looking over my bikes as well as lurking on the frame builders’ list. The 25-year-old Raleigh Super Course is in great shape and no rust. I foresee this one living for many more years. My Serotta is a solid, stalwart frame that I’m sure will match the Raleigh for longevity. My aluminum Bianchi on the other hand, though very light and fun to ride will die long before the other two. It’s by far the lightest bike I have ever owned, but it will die if I continue to ride it as I do now.

My original question was really about comparing older steel tubing to newer steel/alloy tubing (which I didn’t make real clear ). But please feel free to add info about the other materials where appropriate.

From a strictly non-engineering POV, it seemed logical to think that the thicker walled tubing of old, though not as stiff as the thinner OS grade tubes of today, would handle stresses over a longer period of time. A longer cycle life? Thinner walled OS tubes though stronger, lighter, and stiffer in the short run end up having a shorter cycle life?

Now, whether a “cycle life” means anything to the individual is another question. If you like to upgrade every few years then it’s really a moot point. Sell it and let others worry about it. But, if you tend to keep things and use them till they die, it may be more of a concern. One should reasonably expect that if you pay $2,000 - $7,000+ on a frame/bike, it would last for quite a few years of regular use.


>>Quote:
as I've said before on this board, I've so few things I really know that when the topic comes up I tend to go off. I'm a metalllurgical engineer by training >>

Germanboxers…....I WANT TO PARTY WITH YOU!!


William
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Posted by zap:

Germanboxers-great posts.

Regarding stiffness (tube) and tensile strength, I had an interesting discusion with CoMotion when specing our tandem 12 years ago.

My wife and I tested a CoMo which was very much to our liking. Great ride with very good lateral stiffness which is very important in a tandem frame. I was informed that CoMotion had just started building the Double Espresso with Tange Super Prestige tubset which has significantly higher tensile strength than the True Temper tubed bike we tested. The Tange Prestige tubed tandem frameset would be 2-3 lbs lighter. Boy did my ears perk up

I knew that anything lighter would have less material, so I thought the Super Presige would create a wippier frame. I also did not believe tensile strength contributed to the stiffness of the tube. Additionally, tubing diameter between the two was virtually indentical.

Not wanting to sacrifice lateral stiffness, I asked CoMotion about this and they did confirm that thicker walls and/or larger diameter contributes to frame stiffness, not tensile strength. Larger diameter Super Prestige tubing was not available at the time.

So we got the heavier, stiffer bike and have been happy with our choice for 12+ years.

The amount of material also affects fatigue. As William points out, thicker tubes will last longer. But, larger diameter tubes will be put under less stress for a given amount of force extending fatigue life even with thinner tubing.

Higher material strength (tensile) improves fatigue life as well.

Whats different about Al alloys is that the fatigue cycle to failure is different from steel alloys. Under repeated "full" loading, steel will constantly slope downwards with each cycle until failure occurs at around a million cycles.* Aluminum on the other hand decreases slowly past a million cycles until it fails at around 500 million cycles*!

But we know that most aluminum alloys are weaker and less ellastic than steel alloys. So it takes less force for aluminum to begin the fatigue cycle. So designers that use aluminum need to limit the amount of movement if fatigue life is important. So a designer increases tubing diameter or adds more material to acheive this. Remember, aluminum is 3 x lighter than steel.

I know some steel builders think this analogy is stupid, but look at airplanes and how those aluminum wings flex. Some suspension designs use aluminum chain stays (Castellano & Klein) with great success. But they all limit the amount of movement (flex) to increase fatigue life.

As cyclists, I think pretty hard sprints (Pot hole or two ) will introduce fatigue cycles on many bicycle frames. Especially big boys like TooTall and William.

Fatigue cycle tests conducted by EFBe in Germany appear to confirm this. Trek OCLV and Cannondale frames (I don't own either) repeatedly come out on top against steel and Ti frames (and other carbon and Al).

By the way, I'm not an engineer and no one paid me. It's a hobby.

Enough of this, get out and ride.

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Posted by William:

Here is a short but interesting article on how "NOT" to test a frame for failure.

http://hea-www.harvard.edu/~fine/op...frame-test.html

Study up BillyBear, quiz on Monday!


William
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Posted by zap:

William,

Good link. Thanks. I see Anvil are big fans

The plot deepens.

What I can't figure out is how long some (note some) of those Vitus Al noodle frames are still in use. I have a friend that still rides his 16 year old Vitus hard.