boostbutt

hi, my new custom wheels (only have 500kms on them so far) broke a spoke on the non-drive side on 2 occasions. Once at 200kms where I brought it back to the LBS and he replaced and retrue-ed. I got a couple of spare spokes in case it happens on a long ride. This morning, same thing happened again 20kms from my destination. What a bummer. And I thought custom built wheels are supposed to last??

I'm using 15 gauge straight spokes (32 spokes, 2X cross lacing on drive and non-drive side, Mavic OP/Ultegra/Phil Woods spokes) BTW...and i weigh about 88kg at the moment. I do some light sprinting (my max is only 45km/h anyways!) very rarely and the roads over here in Singapore is not bad at all.

So here's where i need advice....

- thinking of actually re-lacing the whole rear wheel with either 14gauge straight spokes (thicker) OR spend a bit more with double butted (what size btw? do you think is reliable).

- i still need the wheel in coming weeks so I will for the first time replace the spoke myself. It looks simple enough (the thought of waiting a week to replace at the LBS is not acceptable) to change..can i just place the new spoke in and tighten until the wheel is true (it appears to be only untrue at the point of spoke breakage). Or do i need to release the tension of all spokes and re-true the whole wheel again? (I think this is too much of an undertaking for me!)

- does higher spoke tension really make a stronger wheel??


Appreciate any thoughts/advice. Thanks.

Basil Moss

Ok, firstly please get double butted spokes. DT Champion are excellent. With a high quality spoke it's hard to go wrong. Higher spoke tension makes a stiffer wheel that stays true longer, but if the spokes are cheap, it breaks them. Are they quality spokes? Or just no name wire? Get the DT's, you won't regret it. Also when you rebuild it, only do 2X on the drive side, and 3X on the non drive side- it will make for a stiffer wheel, and compensate for the offset dish.

Coyote2

^^^^^^
Disregard

DT Champions are not - NOT - double-butted. DT's Competitions are double butted. They are better than straight gauge.

For 32h wheels, 3x lacing is standard and strongest. Just go 3x all around.

Insist that the LBS re-do this at no charge, since they screwed up - even if they did not use the best spoke choice, the wheel should NOT be breaking spokes this soon. In fact, if possible, just get your money back. At a minimum, have a different mechanic rebuild the wheels, and/or get them rebuilt and then take them to a competent wheelbuilder for a final check.

well biked

Coyote2 has good advice.

One other thing, and this is critical for a strong, durable wheel: max. spoke tension for the Open Pro rim is 110 kgf, according to Mavic.

The shop should shoot for this tension on the driveside rear spokes, aiming for uniform tension on the drive side with the wheel round and true, dishing the wheel as necessary, and all should be well.

Your broken spokes are almost certainly a result of an improperly tensioned wheel-

San Rensho 

Breaking spokes on the non-drive side is a classic symptom of spoke tension that is too low. Its counterintuitive, but loose spokes break before tight ones because what happens is, as you ride you apply torque to the wheel which causes some spokes to loosen, if they are loose to begin with, then they will go completely slack and then tighten quickly when you let up on the torque. This loose/tight cycle quickly breaks the spokes.

SUGGESTto the LBS that they re-tension the wheel. If they can't get it right after one shot, get your money back.

brianappleby

yup, LBS likely doesn't know what it's doing.

1 week to replace a spoke that should take 5-10 minutes of labor is also totally unacceptable.

Retro Grouch 

Now think about this.

You had a pretty new wheel that broke a spoke. Took it back to the LBS who replaced the broken spoke and retrued it. All that the LBS did was to return the wheel to what it was before. What it was before (as you found out) was a wheel that was about to break a spoke.

I totally agree with the other posters who suggested that your wheel simply needs to be retensioned. My bet it that'll fix it permanently. It's not a big deal to do.

Incidentally, you also mentioned rebuilding the wheel with 14 straight gauge spokes. Bad idea. I assume that you're thinking that more material will make the spoke stronger. Logical, but wrong. Where did the spokes break? Right at the elbow - right? 14/15/14 gauge butted spokes are already 14 gauge at the elbow so you aren't adding any material where it will help. There's a school of thought that butted spokes skinnier biddle section is more elastic and consequently reduces the strain at the elbow. That would indicate that the spoke with less material is actually stronger in use. Sometimes less really is more.

Coyote2

The original post indicates that they built with 15 ga straight spokes; 14 ga straight spokes would be better, but as you suggest 14/15/14 would be best.

Again, it was stupid of them to use 15 ga spokes, even more stupid to build a wheel so badly that it started breaking spokes at 200km, even more stupid to simply replace a spoke rather than wonder "what went wrong" and re-do the whole job correctly. I'm not sure that I would let this shop fix a flat tire for me. The wheel should be rebuilt, as two broken spokes suggests that the other 14 spokes on the non-drive side have probably been pretty well stressed, too. And I would not trust the same mechanic (perhaps not even the same shop) to rebuild the wheel properly. If they knew how to do it properly, they would have done it properly the first time.

Basil Moss

Oops! Got my spokes mixed up... Basically double butted spokes are the way forward, I can't see any reason to use straight gauge except to save money.

SoreFeet

I don't understand why you keep breaking spokes on your custom wheel. I'm not a complete expert wheel builder. Your symptoms suggest that the wheel was never properly stressed when it was built.

Pull your tire off and check for defects in the rim. Maybe you are one of the lucky few who has a bad eyelet on the rim. Look for anything suspicious. If there is a defect in a newer rim the shop and mavic should warranty it.

Good luck.

ericm979

That's one of the causes....

And that's the other. A taller profile "aero" rim will be stiffer and will flex less. The rim flex is what causes spokes to go loose momentarily where the tire meets the road, which is what eventually makes them break. If the spokes have enough tension they won't go momentarily loose. But the stiffer the rim the less extra tension is needed.

If the wheel can be tensioned to get enough tension on the NDS spokes it should be ok. It'd be better if the wheelbuilder respoked it with double butterspoked. If you are going to pay to get it rebuilt, consider going to an "aero" rim. It'll make a sturdier wheel and if you pick a good rim it won't add much weight.

boostbutt

Thanks for the advice. I was actually thinking of getting lighter wheels that's why I went for the 15gauge spokes. LBS did mention about 14gauge but did say 14gauge is strong too which made me say 'ok'. Partly my fault then!

Guess I'll get it rebuilt with 14/15/14. I was actually hoping the LBS would recommend something ok for my size but looks like they didn't!

Paniolo

When you go back to the shop ask them to use a tension meter on the drive side spokes and tell you the reading(s) They should be very close to the 110 kgf spec. My bet it the drive side are substantially below this, therefore non drive side even less leading to the cycling mentioned above that broke your spokes.

flyguy676

lose weight

cyccommute 

I agree that 15 gauge is too light for you. Your best bet would be to go beyond the 14/15 (2.0mm/1.8mm) and get DT Alpine III. Those are 2.3mm/1.8/2.0 (13/15/15). They make for a much stronger wheel without too much in weight penalty. Think of them as having reinforced heads.

I use them for everything from mountain bike wheels to touring wheels to road wheels. My mountain bike wheel was just retired (bad hub but no spoke problems) after 8 years of hard service to a guy of your size.

PlatyPius

It rarely has anything to do with weight. The most common cause of broken spokes that I see, aside from improper spoke tension, is poor riding style. If the guy is a pedal masher or just doesn't ever get his butt off of the saddle, he's going to break spokes. Some people just don't know how to unweight the rear of a bike when riding over rough stuff.

boostbutt

i'm hardly a pedal masher...but you are right....I seldom ever get my butt off the saddle! does this make a huge difference in breaking spokes? BTW, the spoke broke when I was doing constant speed on a flat, good road.

boostbutt

upz..while I wait for my double butted spokes to arrive, I want to still ride. I have spare 15 gauge spokes with me and plan to replace the broken spoke this weekend. so I read a lot about doing this but what I want to try doing is also at the same time, up the tension a little.Since i don't have a tension meter, I do not plan to release the tension prior to installing the new spoke.

I will just install the new spoke, get it to the same tension as the rest of the non-drive spokes. Then can I just increase the spoke tension on the drive side uniformly buy say 1/4 or 1/2 turns on all drive side spokes and then increase tension on the non-drive side to get the wheel true. Am i missing something? thanks...

Coyote2

What happened with your wheel? Was it rebuilt?

boostbutt

planning to rebuild it but spokes not available at the moment, need to order. In the meantime I still need my wheel....