For the second weekend in a row I have managed to snap spokes in the rear wheel of my road bike.
The first time, I could link the sanpping to hitting a pot hole the dul ping as the spoke head snapped off at the hub coincided with the impact.
Having had the spok replaced and the wheel trued, a spoke snapped within 25 miles. Pot holes were studiously avoided and there wer no significant jarring loads on the wheel prior to the second spoke failure. Is this just bad luck or should I consider having the wheel re-laced with heavier gauge spokes? I am still a porky 20 stone the wheel has a Shimano Sora hub and a Rigida rim if that is any help.
For the second weekend in a row I have managed to snap spokes in the rear wheel of my road bike.
The first time, I could link the sanpping to hitting a pot hole the dul ping as the spoke head snapped off at the hub coincided with the impact.
Having had the spok replaced and the wheel trued, a spoke snapped within 25 miles. Pot holes were studiously avoided and there wer no significant jarring loads on the wheel prior to the second spoke failure. Is this just bad luck or should I consider having the wheel re-laced with heavier gauge spokes? I am still a porky 20 stone the wheel has a Shimano Sora hub and a Rigida rim if that is any help.
Its a badly built wheel. You don't need heavier gauge spokes, you just need the ones you have used properly. The problem you have is the spoke tension is too low and the spokes have not been stress relieved after the wheel was tensioned. Ask around the local clubs for a good local builder or else spend the money instead on The Bicycle Wheel by Jobst Brant and a spoke key and do it properly yourself.
Good advice Tony but 20 stone is a lot. I'm big and it's like me touring carrying more than 5 stone of luggage, which is 70 lb. I've never carried more than 35, and I was lighter then. If a rebuild does not solve the problem, he might need a really strong wheel.
Good advice Tony but 20 stone is a lot. I'm big and it's like me touring carrying more than 5 stone of luggage, which is 70 lb. I've never carried more than 35, and I was lighter then. If a rebuild does not solve the problem, he might need a really strong wheel.
I'm four stone lighter and ride 36 spoke wheels on some quite rocky off-road which gives them a pounding they will never see on road plus I ride 40 spoke wheels on touring tandems with luggage for two, two people and only two wheels to carry all that weight with only 10% more spokes. A standard 36 spoke wheel will do fine for 20 stone if properly built.
All the same, a hand tensioned wheel should be strong enough. I know people who ride tandems with 36 spoke wheels,
When I took the wheel in the first time, I asked about heavier gauge spokes and the LBS reckoned that heavier gauge spokes should not be necessary. The tension on the spokes after repair was noticeably higher. I'll ask again when I take the wheel in tomorrow.
None of my other bikes have had this problem. I've only done 250 miles on the road bike. Perhaps it's the highly strung nature of such beasts. :-)
Its a badly built wheel. You don't need heavier gauge spokes, you just need the ones you have used properly. The problem you have is the spoke tension is too low and the spokes have not been stress relieved after the wheel was tensioned.
1. The wheel probably was built poorly, but still, some spokes are better than others and it's sensible for heavier riders to use better than average spokes.
2. Jobst Brandt claimed low tension does not increase fatigue when I mentioned the subject on rec.bicycles.tech. So probably lack of stress relieving and/or inadequate spoke type/number is responsible for Vernon's problems rather than low/uneven tension (which is more relevant to general strength and ability to stay true).
For the second weekend in a row I have managed to snap spokes in the rear wheel of my road bike.
The first time, I could link the sanpping to hitting a pot hole the dul ping as the spoke head snapped off at the hub coincided with the impact.
The pothole was only the final straw. The spoke will have been fatiguing all the while before that.
Quoted message said:
Having had the spok replaced and the wheel trued, a spoke snapped within 25 miles. Pot holes were studiously avoided and there wer no significant jarring loads on the wheel prior to the second spoke failure. Is this just bad luck or should I consider having the wheel re-laced with heavier gauge spokes? I am still a porky 20 stone the wheel has a Shimano Sora hub and a Rigida rim if that is any help.
You may not /need/ better spokes (I don't know what you've got) but DT Alpine III (2.3/1.8/2.0) should be ideal if you do ever respoke the wheel or get a new wheel. Also consider switching to a 36-spoke rear wheel if you have a 32 now. It's important that the spokes are properly stress relieved*. Not all builders do this, unfortunately.
