Crankshaft Bearings loose inside Crankcase

Guys hi!

Got a KX250 2004 and it is the third time opening the engine.

Now the engine gets a new crankshaft and bearings. Last time I changed also the bearings and that time one of the bearing was a bit loose inside the crankcase. I used special bearing bond/adhesive to fix the bearing in the case.

It worked good but this time I want a real strong solution as the play became a bit more as before.

So I heared people here make very very thin copper rings at a turner and place them between bearing and crankcase.

Has anyone experiences with this?



A friend of mine repaired a set of cases for one of his vintage bikes. He machined the bearing insert and pressed a machined sleeve in place. He races this bike often and has no problems.

They are called speedi sleeves I think.

Not sure that's the best solution though. How loose are we talking about?

Are you sure you have the right bearings?

I've never seen that happen to cases. It's odd.

If pressed out numerous times, that cases can get galled or worn. I usually heat them up in the oven before pressing them out. Then I heat the cases, in the oven, and freeze the bearings. They pretty much drop right in then.

The case needs to be machined for a proper repair... Guys repair suzuki LT500's all the time with inserts...

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