As title says it runs ok up to 4000revs then hesitates then charges on, had carbs off cleaned jets Im wondering plug leads? any thoughts

Hi Alan

I had a similar prob with my XJ 900 divi all that was needed was the carbs balancing properly.

Definitely sounds like the carbs are outta synch

took plugs out and she appeared to be running a bit lean so I raised the needles up one notch and what a dfference she pulls like a train now,