Old 06-02-09, 11:23 AM
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Originally Posted by >>ECB<< View Post
Here's what I'm getting at:

If, on the other hand, you have a 50 ring bolted to a 130 mm BCD crank, the spider's radius will basically be 130/2 = 65 mm. That means the ring will have to resist bending over a length of (100-65) = 35 mm.

The upshot of all this is that applying equal amounts of force to either chainring will be more likely to bend the swaged chainring, since the force will have 100 mm of leverage--versus only 35 mm of leverage on the bolt-and-spider chainring.

Something like this (110 bcd here) maybe?
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