A good friend of mine upgraded his bike and gave me his old engine and kit. He gave me a Staton friction kit with a honda gx35. It has been well taken care of, the only problem it has it that he put over 6000 miles on it. The roller looks worn down. It no longer has any grip. I also think while I'm changing that out that a should change the bearings also. Is there anything else that I should be doing. Oh, and how do I change the roller and bearings? I'm all new to this. Thank you guys!