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2012 250r - camshaft bearing destroyed. Is just the bearing replaceable?

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I was riding my bike when a loud rattle formed in the engine. I switched it off straight away and pushed the bike back to the van.

Pulled the rocker cover off today to find a few ball bearings sitting in the head. The R-side bearing has failed and the balls bearings have fallen out, seeing as I only see a few balls I'm assuming the rest have fallen down into the sump. I drained the oil bit no balls have come out. There doesn't seem to be any sign of scorching or wear that would concern me. Maybe I've gotten lucky.

My question is are the bearings pressed on? Am I able to buy two new bearings or do I have to replace the whole camshaft?

Secondly, with the bearing at the top failing, is there anything else I should be checking further into the engine? I can't imagine bearings rolling around near the crank and timing chain would be healthy.

Thanks

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Bearings are replaceable. Both bearings will slide on the cam journal. The right hand side will come off if you remove the decompression system. I would suggest changing both bearings. That involves having the cam gear pressed off and then swap bearing then press back on and redegree cam. Im not sure how much this service would cost but it may be cheaper/easier/quicker to buy a new hot cam or something similar. As for the ball bearings they are likely stuck to the magneto and around that area. I would be concerned about the bearing race material working through the motor, I would suggest full tear down and rebuild. How many hours on the bike?

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Thanks for your reply. I'll pull the side cover off and check the magneto.

There's about 70 hours on the bike from new. Had had a piston and rings, timing chain and guides from 40-50.

I'll need to double check about the race material. Im not sure if it made its way down as there's little room down the gap where the timing chain goes. Hopefully it's sitting under the rockets somewhere where I couldn't see

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