It may be nothing to do with your problem and I've got a Yamaha engine bike, but -

I had a problem that the bike really didn't want to start. Give it full choke and it would fire up, then run really rough, any throttle and it would die. Once it'd warmed up it was a bit better, upto 4k it was dog rough, but once rolling was OK (not right but OK if you see what I mean).

I stripped it down yesterday to have a look. I started it (on choke) and could hear a ticking sound from around the yoke area. Took the airbox off and started it again. I found that one of the coils was sparking from the end down to the fixing bracket. The insulation on the coil had deteriorated allowing the spark to track down to the bracket.