I believe the chain is new or newish.
The present owner hasn't ridden it much but didn't recognise the irregular rattle sound.
So I think it was the first time. It disapeared readily when riden and thereafter.
Mag kill switch. OK also good to know.
Perhaps people fit additional kill mechanisms?
john.whiting wrote:Sounds like the tension is pretty well OK ......be very careful to check when hot ,and check a full revolution or more ,because there may well be tight and loose spots ......if the primary chain has a number of links that are a multiple of the engine sprocket,there will be worn regions in the primary.I know Ariel chains are difficult to remove ,so no need to do that ,if its near new.....but check thru the hole for broken rollers and marked sideplates...........incidentally ,maggie cutout(earthing points) stop the motor at idle ,but wont normally stop it at speed ,for instance if the carby sticks wide open,so dont rely on it.