If you need to check the chain tensioner to see if it still has any adjustment left, it is a Relatively easy job. HOW TO DO IT Just remove the big nut on the tensioner (located at the centre back of the cylinder, below the carbs) which holds the two tension springs (one inside the other) in postition and remove the springs. Then undo the tensioner body from the crankcase. There are two allen head bolts holding it in position. When you remove it from the crankcase, the tensioner arm will be sticking out of the tensioner body. Note how far out it is protuding, then pull it out as far as it goes. If it only comes out 1mm or so more then it is probably time for a cam chain replacement. Lift the ratchet latch on the tensioner arm, push it all the way back in and bolt it back into the crankcase and then put the springs in and do up the big nut.
