i just resently (this weekend) changed the rear axle on my fixie. I am using the origanal cones on the new axle. Sat. when I changed the axles I tightened the cones against the bearing and than put in the spacers followed by the "lock" washers and tighten them down again the spacers/cones. There was no play in the bearing this morning. I had a rear flat today, changed tubes (did not check bearing) and continued on. This evening I noticed the bearing were loose.
Did I just not tighten it enough? Does back pedalling loosing the cones? Does the pressure from axle bolts cause the rear cones to loosing?