I have recently balanced the carbs and the bike runs fine except that, after riding for several miles, the engine revs to high between shifts, and the idle takes a long (several seconds!) time to return to normal idle speed when I come to a stop. I go of the bike yesterday while the idle was still running high, and pushed against the cable track on the right side carb pair, to make sure the throttle had returned to the idle position, which it had. But the idle remained high. So I now know for certain it isn't a stuck throttle, or throttle cable. Any Thoughts? I just Added a bottle of Sea foam to the tank yesterday, so I'll see what that does, as I was thinking maybe one or more needle valves might be sticking open after warm up for some reason.