cam shaft bearings ?

I am giving my old engine a run over and discoverd that the bearings of my cam shaft did not fit tightly onto the cam itself. So I orderd new bearings thinking the old ones were worn out on the inside.

Now I put the new bearings onto the cam only to discover that they still have the same free play on the cam again.

Are they supposed to not fit tightly :)

Or has the cam itself worn out where the bearings fit over :)

I am dutch and not a wizard in tecnical jargon. I hope I am clear as to the problem.

Who can help out here.

good question ... since I haven't had my cam out yet, I referred to the manuals, and I didn't find anything to indicate how snugly the bearing fits, although it definitely does not say anything about being a press-fit, etc ... someone here will have the answer for you soon, ... meanwhile, inspect the cam and bearing mating surfaces (if no telltale friction signs, like bluing, or grooving, youre probably OK) ...

What kinda bike is it?? I know that my 650l's are just slip on bearings, not pressed on like it says on the hotcams site or where ever. Need to know the bike 1st though.


It is a XR600R from around 1990.

I guessed that they might be slip on bearings.....but are you really supposed to be able to jiggle them ?......they have about 0.5 mm play......

Seems to be a lot for a cam to be able to dance around.

Have inspected again and I must say that they are tighter then the old bearings. But not snug tight.......Also have full Haynes manuall but can not fing info about these bearings......


you mention, its an "old engine", so I would assume with some mileage on it, some visible wear would be evident if anything was wrong ... remember: its an XR .... ride it till it breaks (yeah, right) or you get too old to stay on it .....

OK....It has been a while but I am back again.....

Turned out that the Cam itself was worn down where the bearings slipped over, so bearings would never fit the cam anymore. Threw the cam out the window and searched in vain for a second hand cam.....they were all not that good orderd a brand spanking new HOTCAM (stage 2).

Had the Cam shipped to holland, orderd new forged piston, timing chain and sprockets and many more parts, and now the engine is back together and all I can say is........WOW.......Hotcams are gooooooooood.....

Bike definetly has more power over the full range.

Still have a slight tik in the head, I think my rockers are next on the list, but they can wait a while......I just want to enjoy for a while.


keep an eye on your cam followers ... it has been said in these forums, that the Hotcam has a harder surface, that is rough on the followers ... :D

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