Just took the bike for a 50 mile run.

Was pinking a bit and the plug suggests it is running really lean (would too much additive in the petrol do this - measuring was never my strong point).

However, 5 miles from home it coughed, spluttered and banged and now the points are not turning (though they turn by hand, but don't seem connected to the engine).

I have not had time to take the timing side case off yet, but guess that it is some timing cog that has gone.

Regards

Pat

email (option): sacombsashtrees@hotmail.com

HI Patrick,sounds like your magneto pinion has come free on its taper.if this is the case,clean and lap the tapers with some fine grinding paste,re-time the
engine at 7/16 before TDC fully advanced, lock it up and you should be good to go
hope this is all thats wrong
cheers rick

email (option): richardholt@rocketmail.com

Also check that when fitted to the mag there is clearance between the back of the mag drive gear and the magdyno clutch nut which just protrudes through the mags drive end cover. Sometimes the nut and the gear contact each other and prevent the gear going 'fully home' on the taper. If there isn't any clearance you can machine/grind some material off the back of the gear to rectify the problem...Ian

email (option): ian@wright52.plus.com