I recently bought another grizzly, and its an 05 660. Bike is a beater. I got it from the original buyer with a title. But he said it was knocking. upon further inspection it is def a top end peck, not a rod knock. so gotta pull the head, and gonna go ahead and do a piston and rings in it. This bike was used on a farm. it has 3000 miles on it, and looks rough. not maintained very well. What are some other things I may need to look at. Other then fluid changes, are there any common problems to keep an eye out for?