I had a oil seal fail, and the oil ran out. I shut it down when it was sounding loud. I took off the valve cover and the cam is scored, lifters are very wore. My question is can I leave the cam in and just get new lifters? I would guess no! I am happy with stock, but can I get an aftermarket cam cheaper, will it work with my stock parts? How do I get cam out? Thanks. P.S. very tight budget, just bought bike.