Cosmoline

I'm having constant problems with the rear wheel on my Rat Rod commuter. I replaced it early on with a double wide Sun rim and 14 ga. spokes, but even these spokes keep popping out. It happens when I'm stopped at the bottom of a hill or slope and push down to get going. I'm in 1st gear, but somehow the stress is too much for the wheel and it pops a spoke or two. I try to be careful, but this has been happening about once every fifty miles and it's getting very annoying.

Are there 13 ga or 12 ga spokes? Is there a rim tougher than a Sun double wide.

It might be my technique. This is the position of my leg when I push down and the spokes pop. Should I be doing it flat footed or something?

Mothra

Leg's fine, due to the torque-division through the gearing, there's no way human-power can overcome a spoke. Most of the load on a spoke is from the weight and tension. Are you pulling the spokes through the rim-eyelets or are you snapping the spokes at the elbow bend?

If you're breaking 14ga spokes that were new, most likely it's due to the build of the wheel. Too-little tension is the most common source of quick fatigue-failures. That's because on each revolution, the spokes lose tension as they go through the contact point at the bottom. Loose spokes lose all of their tension at the bottom and they go from zero tension to full-tension each and every time around. This fatigues the metal very quickly. The zero-tension also causes the nipples to vibrate and shake loose, causing wheels to go out of true.

Try building the wheel with 14ga double-butted spokes and tigthen them to the high end of the range. Use a tensiometer. Butted spokes stretch a little more, thus they can compress more at the bottom without losing all tension. Wheels stay true longer.

If you're pulling the spoke nipples through the rim, you may have a bad rim or too much tension.

Cosmoline

They're snapping at the bend. I'm thinking about going over to a 13 ga. butted spoke.

rhenning

I suspect you got a box of bad spokes. I would cut all the spokes out and totally rebuild the wheel with three or four cross lacing using DT or Wheelsmith stainless 14 straight gauge spokes. Roger

Chongo

I think it's because you don't shave your legs.

Retro Grouch 

Are you sure they'll fit your hub?

IROman

lose weight ******!

Cosmoline

I'm fiercely proud of my ass! You're just jealous of my power to snap spokes.

Seriously, I'm always going to be hard on bikes. What I'm after is a wheel that's not built just for wee prissyboys in spandex who use little anime girls as their avatars

Cosmoline

No, I'm not. Maybe I need to swap it out with a tandem wheel, but I hope it doesn't come to that.

Mothra

One tip that I've seen a lot of bike-shops mess up on when building wheels. DO NOT bend down the spokes on the outside after you stick them through. This forces the material past its yield-strength in order to take a permanent bend beyond 90-degrees. Then when you tighten up the spokes, the tension pulls the elbow back in the other direction and unbends it to less than 90-degrees. These two load-cycles beyond the yield-strength of the material really weakens the spoke at the elbow. Jobst's book has a good picture of how the spoke elbow fits through the flange-hole at an angle such that the bend is less than 90-degrees.

Also are these spokes breaking mainly on the rear-wheel's drive-side? if so, what's the amount of dish you have in the wheel? One way to reduce dish is to move axle-spacers from the right (cog side) to the left side such that the smallest cog is only about 4mm away from the drop-out and the chain barely clears. This will then even out the left & right side spoke-tension differences.

vaccineman

I kept breaking spokes too, but then again, it was a 32 spoke wheel on a pannier-loaded commuting bike, 28 mm width tires, and a 190# rider. I ended up replacing the back wheel with a Mavic A719 36 spoke from Performance (other parameters are the same):

https://www.performancebike.com/shop/...slisearch=true

I had to true it after its maiden voyage, but it's been great since.

mechBgon

I'd have the wheel rebuilt with high-quality spokes such as Wheelsmith or DT, hubs with reasonably-thick flanges (I like DeoreLX), and have the wheel built by someone who's got lots of experience at the task. Butted spokes are nice, but for heavy-duty setups like this, even straight-gauge 14ga. will give excellent service life if the wheel is built well and re-tensioned after it's had some time to settle in.