Just been maintaining some of my Shimano cup and cone hubs over the long weekend and the lower end hubs are easy as they use loose balls. I’ve got XTR and Dura Ace hubs which don’t as yet need maintenance however when they do I notice that they both use bearing retainers. From my cursory research it seems quality bearing retainers may provide a slight reduction in friction, hence them being used on Shimano’s top end hubs.
So when it comes time to replacing the bearings do I just ditch the retainer and replace with loose bearings plus 1 or 2? Also how important is it to use stainless steel bearings?
Dunno about DA but I replaced the cups + cones + balls + retainers in a set of record hubs not so long ago, the old ball-in-retainer assembly appeared to have some slop in it compared to the new one but I didn’t get forensic about how much retainer wear there was, given that it’s plastic of some sort. If it were me and they were due a change rather than a clean & repack I’d replace cups + cones + balls + retainers all together.
I wouldn’t even replace cones unless the races were brinnelled. Bearings without a retainer would be ever so slightly smoother spinning but it’s unnoticeable really. New loose bearings, new grease, good to go, IMO.
Half the reason that shimano still use “loose ball” over cartridge bearings is that they are serviceable, so unless your hubs have seen in excess of 50K KM or really bad weather all you would need to do is strip the hub, clean cups, cones + bearings and replace the seal. The flaw in the loose ball system is that the cup itself actually wears as well, meaning if it has experienced a small amount of wear and you replace everything else it will wear the cup out much sooner, meaning all you end up with is a nice paperweight.
You would increase the quantity of loose bearings I’m guessing- by looking at the retainer on the DA exploded diagram the righthand side has a couple more. General rule is fit as many as possible?
Never tried 'em. Don’t know what the point would be as they’re covered in grease and rust would never get a chance to develop if being used.
I’ve only ever used grade 25 chromium steel ball bearings with excellent results. This is what was commonly known as “Campy grade”. Your LBS will be able to order them through SCV Imports (Wheels Manufacturing is the maker). Don’t even bother with any LBS or bearing specialist/seller if they don’t stock that grade.
