Summit frame on profile wheelset

I just put a summit frame on my trials profile wheel and the bearings are different sizes. I dont have the shims so the wheel rattles in the frame. Will it mess up my bearings if i ride it until i fix it?

In a word, yes. In fact, after talking to Roger@UDC for a week about bearing issues, even having bearings shimmed up isn’t the best solution. I would assume the bearings you have are the 40mm Profile standard bearings, and you’ve just got a frame (the Summit) that has 42mm holders. The best solution would be to find a set of bearings that are 3/4" interior diam and 42mm outside diam.

I know (thanks to Roger) that the KH/Onza hubset has bearings that might fit, and thats with an internal (inside instead of outside the bearing) shim. Might be worth contacting UDC about getting some different bearings that would fit.


:frowning: :frowning: :frowning: i just rode it so much, hummmm, well, hummmmm.

I’m sure it’s not damaged enough to make a difference, probably shouldn’t do anything on it until you get some shims though. they’re uber-cheap from unicycledotcom.

Having bearings thrash back and forth equals you break your equipment. Get the fixed before you ride on it.

Am I the only person on this forum who things “Bearings, schmrearings!”?

I mean honestly, do you really feel the difference between new and old bearings? Especially on a trials uni. And even if you did, you’re not putting all that much stress on the bearings and you never spin over what, 100 rpm? And even if you were trashing bearings, it won’t be a catastrophic injury causing failure, so who cares? I’ve never changed the bearings on any of my uni’s, even after a ride in Santa Cruz where I got home to find that the bearings, even with seals, were packed with dirt and sand.

So, Bevans saying no big deal?

It’s not a big deal for now, but having that much slop in the bearing holders isn’t good for the bearings. You should put shims on the bearings to make them fit. But there is no reason to stop riding until you get the shims. sells the bearing shims. There are two sizes. One for the 40mm OD bearings and one for the 1-5/8" OD bearings.

1-5/8" is 41.275 mm. That’s close enough to 42 mm that I wouldn’t worry too much at all if you were using the 1-5/8" bearings. But I’d still get the shims for it.

cut a shim to put around the bearings from one of dads beer cans.

dont use a Guiness can since thats a dark beer and therefor your uni will be heavier…go with Bud or Busch light cans.

For trials, I would go with the Guiness shims, as they will be much more Stout.

You should be more concered about what the too small bearings do to your frame than about bearing damage. Tightening the bearing holders down on a smaller bearing will deform them, and running them loose will wear them so that they won’t fit the correct bearing later. The bearing is much more replaceable than the frame. Shimming is fine if done properly.