I had a weird mechanical on my fixd gear. I was pushing hard going up a little hill when I suddenly stopped. The drive side bolt appeard to have slipped, and the wheel toed in and rubbed the chainstay and promptly stopped. I quickly got off the bike to retighten the bolt and as I straightened out the wheel, a piece of metal fell out from next to the axle bolt. I picked it up and realized it was about 3/8 of a nut. Somehow, my guess is possible overtightening coupled with aggressive riding put a lot of stress on the nut on the inside of the chainstay. There was enough of the nut still there to hold the wheel, so I tightenend it and rode home—very carefully and slowly. When I got home, I took the wheel off and the rest of the nut fell off. I guess I am a little concerned because I have never even heard of this happening to anyone. I have ridden that wheel on the bike for about 18,000 miles over the last 5 years. I ride the fixed gear hard. It has a 48x17 on it and I push the hills—and I have ridden it on a lot of hills- including Independence Pass (from the Aspen side) in Colorado. I have always liked this bike because mechanically there is very little that can go wrong.

I wonder if anyone else has had a similar breakdown.

Train safe-