I needed to replace the bearings on my bike. I'm a former mechanic so I did everything myself and am very happy with the results. Old bearings have "crumbled" to pieces and there are bearings of dubious quality. They passed my rudimentary endurance tests, but time will tell. As always, correct installation involves tightening and backing off the bearing with a wrench until no resistance or play is felt, then locking the adjuster in place. And hope that the generous lubrication is done for good.