Originally Posted by g321

Edit: Picked up the bike and talked to the mechanic again. He said the Specialized rep reported three incidents of failure and all bikes were used extensively on an indoor trainer. I got a chance to see the difference between old and replacement collars and the bolt (facing the drive side) appears to be a little longer. Any other differences were too subtle for my eyes to pick up. Oddly the mechanic said the new torque spec to tighten the bolt is 4nm (I think the original spec was like 6.2nm).