SPARK PLUGS NEED CHANGING AFTER ABOUT 500-1000 MILES,FRONT CYLINDER PLUG IS ALWAYS BLACK , THE BIKE ALWAYS RUNS RUFF . EVEN TRIED SCREAMING EAGLE PLUGS AND IT RAN WORSE.IT HAS BEEN LIKE THIS FOR AWHILE AND I TAKE IT TO THE DEALER FOR ALL IT´S SERVICE LAST ONE WAS 50,000 MILE , NOW HAVE 53,OOO AND HAVE CHANGED THE PLUGS FOUR TIMES SINCE THEN.