if the cam chain has fallen off which it shouldnt and if it has then the tensioner is knackered ,then at least one of the valves will be bent already so you need to take the head off and check the state of the valves before you even attempt to refit the chain.there are timing marks on the magneto and one on the side of the cam sprocket theat lines upwith a pointer on the head.
adam bike doctor(of milton keynes motorcycle centre)
December 2010
you may have bent valves if you have tried starting it with this in the incorrect place
GHOST
December 2010
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