my 450 will not start, the plug is only sparking once to every 20 kicks i've put a new spark plug in but it's still the same will it be an electrical fault or could it be the timing as i had just done the valve clearances.
any advice would be much appreciated
Sounds very much like your coil is breaking down and that's why you are getting a spark now and again, first thing I would do is put a new coil in the bike or get it refurbished