Bicycle Mechanics - Frequent broken spokes

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View Full Version : Frequent broken spokes


samad195
07-29-09, 06:27 AM
I have a brand new Scattante R330 road bike. Every week I cut one to three spokes on the rear wheel, on the cassette side. Other bikers on the same route I bike do not have this problem.


DannoXYZ
07-29-09, 06:29 AM
Have your spoke-tension measured by a competent wheel-builder with a tensionmeter. Most likely your spokes are too loose, leading to premature fatigue failure.

Veloraptor
07-29-09, 11:44 AM
Your spokes could also be too tight. Grab a hold of a spoke on cassette side about half way and wiggle. If spoke wiggles easily then spokes are too loose. If spoke if very tight then go around all spokes on cassette side and loosen half turn with spoke wrench. Spokes opposite of cassette are always looser then cassette side. If spokes are loose then tighten until they are hard to turn with spoke wrench;count how many turns on each spoke so they are all same. Learn to work on your bike. Any book by Lenard Zinn you could find at library. Park Tool Website (http://www.parktool.com/repair/byregion.asp?catid=14&imageField2.x=26&imageField2.y=9)


noisebeam
07-29-09, 11:58 AM
Don't do anything other than to take it back to the store and demand a new wheel. It may not be built better than the first, but there is a good chance it will be.

BigBlueToe
07-30-09, 09:44 AM
This should definitely not be happening. I'm guessing the wheel wasn't tensioned properly. Take it back where you bought it and start by having a good wheel builder re-tension it. Let them know that if you still have problems with broken spokes you're going to expect them to replace the whole wheel for free. Or just start by asking for a new wheel. Make sure someone tensions it so you don't repeat the process.

When I had my local mechanic build me a wheel he spent some time tensioning it, told me to ride it for a month, bring it back, and he'd re-tension it. I think that's how it should be done.

LarDasse74
07-30-09, 10:19 AM
Your spokes could also be too tight. Grab a hold of a spoke on cassette side about half way and wiggle. If spoke wiggles easily then spokes are too loose. If spoke if very tight then go around all spokes on cassette side and loosen half turn with spoke wrench. Spokes opposite of cassette are always looser then cassette side. If spokes are loose then tighten until they are hard to turn with spoke wrench;count how many turns on each spoke so they are all same. Learn to work on your bike. Any book by Lenard Zinn you could find at library. Park Tool Website (http://www.parktool.com/repair/byregion.asp?catid=14&imageField2.x=26&imageField2.y=9)

I have never heard wheel tensioning broken down into such simple steps. Unfortunately, I think it may be a bit too simple to actually help anyone have a stronger wheel.

Anyhoo, the OPs problem is almsot definitely a poorly tensioned wheel - or a wheel that was not 'stress relieved' after being laced, which results in a drastic loss of tension during the first few rides.

I would bring the wheel back to the store where you bought it. They sold you a faulty wheel... unless they first told you it was not finished being built and needs to be stress relieved and re-tensioned before riding.

DOS
07-30-09, 10:24 AM
Tension could be it but also... cheap wheel (i.e. relatively weak rim) + marketing (i.e. very few spokes) + largish rider = broken spokes. How much do you weigh? I go 230, bought bike with wheel with too few spokes, started breaking spokes.

Al1943
07-30-09, 11:37 AM
Broken spokes usually have insufficient tension and on the non-driveside rear. This is due to the asymmetrical tension required in offset flange hubs to make room for the cassette.
Or they are poor quality spokes, damaged spokes, or a poorly designed wheel.

Al