bearings going out after 6 months

I got my kh36 in early December and a couple of weeks ago my bearings started to click and has got progressively worse. Since December I ride it 5 or 6 days a week but I didn’t think the bearings would go out in six months. I ordered new bearings and they arrive tomorrow, or later today but has anyone encountered this problem before?


They usually last longer than that, but they’re not very expensive and quite easy to change so it’s not a big problem. Unless you ride enormous distances in very bad conditions (I’d imagine it’s not that wet in Texas is it?) then I’m surprised they only lasted a few months though… one thing that can shorten bearing life is doing the bearing caps up too tightly and distorting the outer case slightly - when you fit the new bearings make sure you don’t over tighten them (they should be just tight enough to get rid of any play but not so tight they stop the wheel spinning freely - it’s really not very tight, even with a little hand-held allen key)


EDIT: Just noticed your join date - sorry if all that stuff about bearing tightness is old news! If it’s your first ISIS hub though, bear in mind that the ISIS bearings are much smaller and have thinner outer shells to accommodate the larger axle in a similar outer size. You need to treat them a bit more gently than the old type bearings.

Bearing Wear

I have ridden a few unicycles hard for over 4 years now and have never had bearing problems. One thing that I can think of that would wear down bearings is sand. It acts like, well, Sand paper and is a pretty good abbrasive.


It’s very wet and gritty here, which is pretty hard on things like bearings, but mine last at least a couple of years (and even then they’re not utterly unuseable, but I have changed a couple of pairs when they get very rough).

Only lasting four or five months does suggest a problem - either bad bearings or over-tightened clamps.


I replace the bearings after every 1000km on my Coker’s. I can feel that the rolling resistance increase at about 1000km. But I drive a lot of bad roads.

Thanks for the replies. Unfortunately, it doesn’t rain much here. I ride pretty much only asphalt, city riding. Anyway, I changed out the bearings and everything is back to normal. Happy riding, everyone.


This seems like an appropriate thread to post this video. I always thought a bearing fitted a shaft as a tolerance-fit. Thats is, essentially the bearing has to be driven onto the shaft and removed with a puller. Well one side of my ISIS hub begs to differ.

I also have a KH 36, had it for a year and a half now. It is my only form a transportation so I ride quite a bit. I destroy a pair of bearings in 4-5 months, usually they crack and stop spinning altogether. It seems that even with lots of miles they should last a longer. I was worried I was tightening the bearing caps too much, but have the same problem even when I’m very careful about it.