Got my 18 back on the road today
but I have found it has a really frustrating misfire 
At first it only seemed to be at 8000rpm +. After loads of messing and fitting new plugs, checking the RC valve positions, checked the plug cap/HT lead connection, the coil connections and cleaning the carbs its still no better. It seems only to be on the right hand cylinder (but hard to tell) this side is smoking a bit more.
I went out again and tried different throttle openings and at 1/4 - 1/2 throttle she revs to the redline as sweet as a bird through the gears. Then I tried opening the throttle 3/4- to full throttle and she misfires at virtually any revs like 5-6000rpm.
My thoughts go to either the throttle position sensor, the PGM or wildy out jetting. Its a PGM1 running 175 mains on premix which doesn't seem that far out looking at other threads.
How can I check or eliminate the throttle position sensor? Can I just unplug it? or can this do any damage to the PGM.
Any other thoughts or help much appreciated,
Ade