to be honest i bought the bike used and dont know the last time the plugs were changed...

also no i dont have a power comander...

and the idle when the bike is warm almost sounds smooth except every 10 seconds or so it does the studder thing... i have noticed lately that when i really go full throttle from low rpms it almost seems like there is some lag before the bike really gets going, when i go easy from low rpms it goes through the rpms well and smooth