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- bicycle wheels

The following equation comes from a paper by HP Gavin.

LOG(stress)=-.3LOG(cycles)=4.12+.072Z where Z is the normal distribution. If you only have 1 spoke you place it in the middle of the normal distribution that is a Z score of 0. So if you have 36 spokes you divide the normal distribution into 37 parts and use a reverse normal distribution calculator to get a list of the cycles of stress when spokes can be pridicted to break.

It looks some thing like this. 10000 11930 13391 14637 15771 16812 The This assumes you replace a spoke as soon as it is broken. It is obvious that some of the replacement spokes will break before the last original one goes. I'm not going to build that model because I"m too lazy. Few people will tolerate more than 6 broken spokes before they buy a new wheel.

Go to [email protected] to find out what people will put with. I simply want a guideline to help folks choose a new wheel. The experiment that generated that equation used spoke tensions and cycles that were too high to be used in a practical wheel so I'm going to ignore the predicted life of a new wheel with a reduced stress on each spoke corresponding to more spokes or stronger spokes. Instead I will use fatigue curves for high cycles. My worst spokes survived 1000000 cycles before breaking.

What I need is for some one to keep a precise log of the spokes they broke I can then use curve fitting methods to adjust the equation. The equation has 3 constants that can be adjusted. I'm doing this on the cycling forums so far no one has understood the equation. I need some one to tell me if the equation is not valid. I have broken 60 spokes at 5 quality levels. In order to do that I had to build wheels with used spokes and substandard spokes and ride more than 100000 miles. The equation seems to fit my experience.

LOG(stress)=-.3LOG(cycles)=4.12+.072Z where Z is the normal distribution. If you only have 1 spoke you place it in the middle of the normal distribution that is a Z score of 0. So if you have 36 spokes you divide the normal distribution into 37 parts and use a reverse normal distribution calculator to get a list of the cycles of stress when spokes can be pridicted to break.

It looks some thing like this. 10000 11930 13391 14637 15771 16812 The This assumes you replace a spoke as soon as it is broken. It is obvious that some of the replacement spokes will break before the last original one goes. I'm not going to build that model because I"m too lazy. Few people will tolerate more than 6 broken spokes before they buy a new wheel.

Go to [email protected] to find out what people will put with. I simply want a guideline to help folks choose a new wheel. The experiment that generated that equation used spoke tensions and cycles that were too high to be used in a practical wheel so I'm going to ignore the predicted life of a new wheel with a reduced stress on each spoke corresponding to more spokes or stronger spokes. Instead I will use fatigue curves for high cycles. My worst spokes survived 1000000 cycles before breaking.

What I need is for some one to keep a precise log of the spokes they broke I can then use curve fitting methods to adjust the equation. The equation has 3 constants that can be adjusted. I'm doing this on the cycling forums so far no one has understood the equation. I need some one to tell me if the equation is not valid. I have broken 60 spokes at 5 quality levels. In order to do that I had to build wheels with used spokes and substandard spokes and ride more than 100000 miles. The equation seems to fit my experience.

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