T'is true. insulting me is the law.. I think Sir Isaac Newton discovered it alongside gravity and it was decreed by the house of Lords.
It's an Empi. it was a bit nasty - it came with a broken jet - put my old jet in it and it has been brill since. It's the timing I undid the clamp a few month's back when I serviced her and can't remember if I tweaked her by ear before tightening, I probably did, I usually do. Points could do with resetting too.
It will probably fix itself again before I sort it next weekend. Have you noticed how they do that too?
Have you taken it to someone with a gas analyser to set up the carb? Might have drifted off a bit and need tweaking.