Wheels for a fat guy



fitfatguy

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Apr 10, 2006
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I have a Spec. Sequoia Elite, and I'm running into a problem I've had on my older steel bikes, and that is my wheels getting out of true fairly quickly. I'm 300 lbs, and typically ride 70+ miles/week on fairly rough roads. I'm debating whether or not to get another having a set made for me, or just let the LBS true the wheels up every month or so until I lose enough weight where it shouldn't be an issue(50 lbs or so), which I should be able to do by Thanksgiving. This is my current setup:

RIMS Alex AT400, 700c double wall rim, machined sidewalls, spoke eyelets
FRONT HUB Specialized forged alloy, 28 hole, double cartridge bearings, QR
REAR HUB Specialized forged alloy, 32 hole, double cartridge bearings, cassette, QR
SPOKES Stainless 14g
I'd rather not have to buy new wheels if I can avoid it, so what are my options?
 
I'm 90kg and have had trouble with road 32 double-butted spoke rear wheels and also with a 20 spoke rear R550, in terms of a slow worsening of uneven spoke tension until the spokes start to break.
I've never had trouble with 36 straight spoke MTB rear wheels ridden harder on rough roads and tracks.
I've found that three things are most important:
1. use straight (non-butted) spokes: the increased spoke stretch resistance seems to lessen the cyclic tightening/untightening of spoke tension that allows the spoke nipples to loosen themselves.
2. the more spokes the better. you may get away with 32 on the rear, but 36 would be better. (low spoke count wheels feel dead anyway :cool: , go ahead, flame me...)
3. Have an EXPERT wheel builder build or retension your wheels. This makes a big difference. Any wrench can build a nice looking wheel, but few can build a good strong one, I've discovered. If the wheel pings when you ride, even if only when you're standing and stomping hard, it's not good enough and needs to be retensioned, not just trued. If it pings, take it back or take it to someone competent enough.
 
fitfatguy said:
I have a Spec. Sequoia Elite, and I'm running into a problem I've had on my older steel bikes, and that is my wheels getting out of true fairly quickly. I'm 300 lbs, and typically ride 70+ miles/week on fairly rough roads. I'm debating whether or not to get another having a set made for me, or just let the LBS true the wheels up every month or so until I lose enough weight where it shouldn't be an issue(50 lbs or so), which I should be able to do by Thanksgiving. This is my current setup:


I'd rather not have to buy new wheels if I can avoid it, so what are my options?

I suggest that you use 36 spoke wheel built well.
Strong stiff rims help a significant amount. Velocity Deep V is a good choice.
Unlike the other respondent, I strongly suggest 14/15 double butted spokes built in 3 cross and properly tensioned. The additional stretch in a tensioned 14/15 double butted spoke allows the dynamic loads to be spread over more spokes, and a broader section of rim and hub. This increases wheel durability.
Spoke alignment, tension balancing, and stress relieving make a huge difference in wheel durability. 300 pounds will force the wheels to be very durable.
I also suggest checking the frame/fork/brakes to see how large a tire you can mount. If you can start with 32 mm width tires that will help cushion yoour ride and better protect your wheels. 30 - 28 mm should be a minimum for a rider of your weight riding on roads you describe.
 
daveornee said:
Unlike the other respondent, I strongly suggest 14/15 double butted spokes built in 3 cross and properly tensioned. The additional stretch in a tensioned 14/15 double butted spoke allows the dynamic loads to be spread over more spokes, and a broader section of rim and hub. This increases wheel durability.
This is an interesting topic. Dave, I respect your experience but a number of local wheel builders have suggested non-butted spokes for heavier riders. Certainly, but obviously anecdotally, my first adequate rear wheel (of 4) on my road bike has been one built with non-butted spokes. I say adequate in that it does not ping even when pedalling hard out of the saddle, unlike the three previous wheels that all ultimately failed. This could be, of course, because I had it built by Sydney's best wheelbuilder (by reputation).
What do others think? Does anyone know of any data?
 
dougal said:
Who is Sydney's best wheelbuilder out of interest?
That accolade seems to be awarded to Steve Hogg of "Pedal Pushers" in Rosebery. Of course, it is a matter of opinion and the subject of dispute... ;)
I can recommend him, so far (I've only put a couple of hundred km on the wheel ).
 
artemidorus said:
3. Have an EXPERT wheel builder build or retension your wheels. This makes a big difference. Any wrench can build a nice looking wheel, but few can build a good strong one, I've discovered. If the wheel pings when you ride, even if only when you're standing and stomping hard, it's not good enough and needs to be retensioned, not just trued. If it pings, take it back or take it to someone competent enough.
What is pinging? I haven't heard any strange noises out of the wheel so far. My main concern is what the effect truing and retruing will have on the wheel long term if I have to do it at best on a monthly basis.
 
fitfatguy said:
What is pinging? I haven't heard any strange noises out of the wheel so far. My main concern is what the effect truing and retruing will have on the wheel long term if I have to do it at best on a monthly basis.
Pinging is a high-pitched metal-on-metal percussive noise that the spokes make as you pedal. They shouldn't do it.
If you don't get the wheel retensioned, then you are likely to experience an accelerating rate of going out of true, and spoke breakage. This is because repeated retruing usually leads to increasingly uneven spoke tension; the tighter spokes eventually break.
 
I'm a pretty big dude...I've been riding Bontregars on my road and mountain bike. they're pretty f'n tough.

I have a truing stand where I volunteer and they always seem to be really close even after a beating. Maybe it's my cat like finess...
 
artemidorus said:
This is an interesting topic. Dave, I respect your experience but a number of local wheel builders have suggested non-butted spokes for heavier riders. Certainly, but obviously anecdotally, my first adequate rear wheel (of 4) on my road bike has been one built with non-butted spokes. I say adequate in that it does not ping even when pedalling hard out of the saddle, unlike the three previous wheels that all ultimately failed. This could be, of course, because I had it built by Sydney's best wheelbuilder (by reputation).
What do others think? Does anyone know of any data?
DT says:
"Why are spokes thinner in the middle, espcially on more expensive bikes?

Such butted or reduced spokes increase the life of the wheel. Spokes with a smaller diameter in the middle are not only lighter and more aerodynamic, they most importantly have significantly better elastic properties than conventional straight spokes. They react to extreme overloads in a similar manner as the butted bolts used in machine construction. If the wheel is subject to radial impact, the affected spokes absorb the resulting overload like a spring, protecting the hub."

Sheldon Brown says:
"Double-butted spokes do more than save weight. The thick ends make them as strong in the highly-stressed areas as straight-gauge spokes of the same thickness, but the thinner middle sections make the spokes effectively more elastic. This allows them to stretch (temporarily) more than thicker spokes.

As a result, when the wheel is subjected to sharp localized stresses, the most heavily stressed spokes can elongate enough to shift some of the stress to adjoining spokes. This is particularly desirable when the limiting factor is how much stress the rim can withstand without cracking around the spoke hole."

Sapim says:
"Sapim butted spokes have two major benefits: less weight and more strength! Technological advances using cold forging (SAPIM Forging Technology) 'stretch' the spoke, retaining the linear molecular structure of the material, thereby increasing the spoke strength at the middle by at least 48%. As an added bonus, the thin middle section of the light Laser and Race spokes also provides better shock absorption. "

Jobst Brandt says:
"Butted spokes are more elastic than unbutted spokes. Under load they resist lossening better than straight spokes. Their resilience helps the rim distribute loads over more spokes and reduces peak stress changes. Butted spokes are lighter without giving up any strength....
Straight spokes greater stiffness reduces elastic interactions among spokes which, in turn, subjects them to higher stress by concentrating loads over fewer spokes."

I see 4 advantages of straight spokes:
1. cheaper
2. stiffer (relative to same wheel built with butted spokes)
3. when one breaks the wheel will go slightly less untrue due to the lack of interaction of and relative stiffness of remaining spokes.
4. Easier to build with due to smaller elastic interaction amongst spokes.

The disadvantages outweigh the advantages, in my book, because the wheel built with straight spokes is less durable. The increase in durability with butted spokes more than makes up for the additional costs. Rims and hubs are dynamically involved too. Since the elasticity of spokes is only one portion of the overall wheel, rims and hubs built with double butted spokes benefit from the additional elasticity compared to straight spokes.
 

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