undo the rear wheel nut just two turns then look at the back of the bike and you will see two chain adjusters in he end of the swinging arm,turn them equal amounts and get about 1/2 inch of free play in the middle of the chain then do the nut back up tight ,there are marks on the side of the swing arm to get the chain adjusters level and make the bike ride in a stright line.
adam bike doctor
February 2007