Cannondaleriders

Hello all, a few months ago after returning from a long ride in Glamis I noticed a lot of metal shavings in my inline oil magnet (big thanks to John for that nice sight glass). The quad was still running great but I decided to park it for the rest of the trip.
I finally found some time to pull the motor and try and track down the problem. I found the crank bearing race on the crank plate side was going out. Everything else on the motor seems fine.

My question is what could have caused this and should I be concerned?

Should I be worried about any other bearings going out? Would it be good idea to replace the bearing on the other side as well?

Should I be worried about the main bearing failing? It???s a Timbo Stroker and it doesn???t have a a lot of hours on it and it ???feels??? fine but I don???t want to be tearing this thing down again anytime soon.

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The bearing race has fretted. It is a common issue of a worn bearing. Riding in sand does accelerate the wear. Yes, I would replace both bearings. I would also replace the starter one way bearing while you are in there for cheap insurance.

Those bearings do fatigue out on rare occasion but since it was caught early before the crank started to flop around the rod bearing will be fine. If driven till there is a channel worn through the race the timing chain and chain guides get stretched and broken. If no metal made it back into the engine through the frame you might get away with just scavange pump rotors and new main bearings. Did you notice the engine knocking at low rpm or just caught it with the sight glass inspection?

No, I did not notice the engine knocking I just happen to check the sight glass and could see something was wrong. I think I???ll go ahead and replace all the bottom end bearings and the scavenge pump rotors just for peace of mind.

Thanks for the responses.