THIS BIKE IS EXELLENT IN EVERY WAY. EARLY BIKES YOU HAVE TO FACE AIR SCOOP TO REAR OF BIKE FOR MUCH IMPROVED PERFORMANCE . ALSO MAKE SURE MIXTURE IS SET AT 1TO11\2 TURNS FROM IN AS MOST ARE SET AROUND 2 TURNS FROM IN. THE BIKE SHOULD BE MORE WILLING TO REV STRAIGHT THROUGH THE TACHO AND NO FLAT SPOT.