I am the original owner of a 02 WR426. It has been an awesome bike! I probably have at the least 8000 miles on the original motor. Still runs great! I have always kept the valves in spec and done the other regular upkeep. It's loosing a little compression and recently the jetting has been off...........? I know it is getting tired and needs some love. Can I just put in a new piston..... As long as the cylinder is clean or do I need to redo both the cylinder and the piston? Or can I just put in new rings? Will the bottom end hold up to a new piston? Who makes the best pistons? If the cylinder needs work, who should I send it to? I know alot will depend on what I see when I open her up, but any advice before hand would be greatly appreciated.