[rakehill]

Thanks Vic
The mag is a temporary BTH one whilst Dave Lindsey repairs the ML after shellac problem. I did notice the hesitancy before that problem and so think that a bit of an overhaul is due and I might as well get it done whilst the proper mag is away. I did Banbury this year and the plug looked perfect at the end of it even though the mag had a melt down after the finish.

[VicYouel]

A Brooklands motor cyclist competitor from the thirties once told me that 98% of problems were due to the electrics. So to be sure you need to check out the points and plugs first. when was the magneto last overhauled by a professional? Try a new plug as well and make sure it does not have an integral suppression resistor like all modern plugs.  I like the "green spark plug company" ML50 long reach one.

[rakehill]

I've noticed hesitancy when I open the throttle quickly and think that it could be time for a decarb. The side valve cylinder is solid without a detachable head. I know that I can easily remove the valve caps and the cylinder plugs. I expect to take the cylinder off the bike and remove and re grind the valves. The cylinder itself though must be difficult to clean. Are there any special techniques for doing so that you guys know about. The hesitancy in the pick up from idle is a fairly new thing. Could it be due to the carburettor? if so I would have a go at that first.