Um, I’m still wondering: a) Tigthening the bearing caps until they “brake” the wheel and then loosen them until they don’t do it anymore?
b) hand-tighten them (as I wrote - at least for me that’s before “a)”)?
c) yet something else?
What happens if I don’t tightem them enough?
(I have not found the answers in the forum, just a lot about a and b combined. I’m sure the answers exist somewhere though, so feel free to yell at me and tell me which key words to search for… ;))
I am not a bearings specialist but based on my experience with a couple of muni without brakes: if they are not tight enough, you hear a loud creaking when torquing uphill or downhill.
I always use a L shaped hex wrench to tighten evenly the cap holding it by the short side. Then when I cannot tighten more I am done. Works well on my KH frame.
On my Flansberrium, I add a tiny-tiny extra by turning the wrench around and turning 20 degrees only on one bolt by pushing with my thumb right after the wrench elbow.
Under tightening will torture the bearings with lateral stress and over tightening will prevent it from rolling properly (maybe aging the balls inside prematurely).
Thanks! So I’ll make sure it’s tighter than hand-tight.
I don’t have a fitting L hex wrench, but I guess I’ll have about the same amount of lever with my dogbone wrench / dumbbell spanner or an equivalent multi-function flat b*ke tool.
visualize what is happening
The outer part of the bearing is made to be round. If you tighten the caps enough, it will warp round to oval. This will be shown by how an oval (over tightened) bearing will not allow the wheel to spin as many reps.
Bearings are both cheap and tough, so yes, you are being anal. Getting this wrong will take a long time to cause an inexpensive FUBAR.
But I am anal to, so while we are on the subject, if you want to be perfect, use blue loctite (yes it has to be blue). Flip your uni (while you are not on it) , then, with the caps full loose (so the bearings are full round), spin the wheel with a standard thrust of 17 newton pecks /kiloparsal squared, as we all do. Then count the reps.
With the blue loctite on the cap clamp threads , slowly tighten the clamps until the standard spin slows down. This means you have warped the bearing, in a temporary, harmless way. Then loosen 1/4 turn. Perhaps less or more than me, but I am so anal I actually care about this stuff. 1/4 turn that leaves the wheel spinning so free that it achieves full free spin is the gold standard. The blue loctite, once dried, will prevent the caps from loosening.