Freestyle Replacing Caged Bearings for Cageless Needle-pin Bearings

[dcptr]

I will never use caged wrist-pin bearings again. The cost vs. lifetime of cageless outweighs its predecessor.

I'm currently fitting the Sea-doo 951 cageless needle-pin bearings to an xscream 10mm crank and noticed that there may be a slight problem..

The bearing is 4mm narrower than the inside opening on the piston. The cageless bearings have a thin ring on each side, holding the needles centralised in the crank around the wristpin. My thought is- the clearance outside the bearings may allow the thin outter rings to drift from side-to-side, which in-turn wont keep the needles centralised either.

Should I be installing shims to chock in between the outside gaps to keep the bearing rings in place?

Refer to attached photos for a better understanding..

*The second photo is a measurement of one of these outter rings, holding the needles in place.
*Last photo is the cageless bearing, with the inner & outter removable plastic casing

 

[special fx]

I worried about this too, but in the end I decided to run them this way. So far, so good.

 

[BruceSki]

X2 no issues with mine.

 

[dcptr]

I worried about this too, but in the end I decided to run them this way. So far, so good.

Your running them as is? No shims?
What engine/pistons?

 

[special fx]

Your running them as is? No shims?
What engine/pistons?

Team Scream ss865 with their pistons. I looked at my Dasa pistons and there's no way they would work with them without some sort of shim. The Dasa pistons have a way larger gap.