My diagnosis to Jan Wolter's axle bending/breaking problem is :
misaligned rear dropouts.
When the dropouts are not parallel, they put great force on the flats
of the axle. This eventually ends in bending and breaking the axle.
The dropouts can become misaligned due to accident (esp. one which smashes
the derailleur) or mishap (someone kicks your bike while its parked).
So Jan, take your bike to a pro bike shop where you can get your rear
triangle checked for alignment and get your dropouts lined up.
Joe Bike
Univ. of Virginia, Charlottesville
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