Been fighting a hanging idle for quite awhile on this bike, the other day, after a water pump rebuild and float level check it started 'hunting' for idle....would idle smoothly for a minute or so, then jump to 2100 for 15 - 20 seconds and drop back to idle.
A guy on the XJ forum said it was a sync problem....'it's close but not close enough'. I was real skeptical about that but hooked the Carbtune up anyway....one of the center cylinders was a couple lines off so I dialed it back in and sure enough....it felt and sounded like a different motor. Idles smoothly with no change in rpms, snappy off idle....sounds like it did when I drove it away from the dealers....29 years ago!
I never would have thought that tiny a change would make THAT much difference. Guess these little motors are 'zero tolerance sync', it's either perfect, or it's wrong!
A guy on the XJ forum said it was a sync problem....'it's close but not close enough'. I was real skeptical about that but hooked the Carbtune up anyway....one of the center cylinders was a couple lines off so I dialed it back in and sure enough....it felt and sounded like a different motor. Idles smoothly with no change in rpms, snappy off idle....sounds like it did when I drove it away from the dealers....29 years ago!
I never would have thought that tiny a change would make THAT much difference. Guess these little motors are 'zero tolerance sync', it's either perfect, or it's wrong!
