Hi. Long time reader, first time writer here. Working on a 300 fourtrax. The cam chain was sooo loose that it would hit the guide and then the guide would hit the tensioner. Making a "tapping" noise. No big deal. So I changed the chain. When I go to time it the marks on the cam sprocket will be straight across the head with the punch mark on the sprocket at the top. But if I check the crank it is off by 1/4" or so. No problem I think, I am one tooth off, move it and I am almost lined up with the " f " mark. What is my problem? I pulled the flywheel cover off to check the key way had not sheared off moving the markings. Everything was good there. Any Ideas would be great.