Yes I did changed the front sproket ftom 15 to a 17 and from 46 to 42 on the rear.Bike attains highway speeds easily 70 75 mph and the engine works very nice and changed fuel consumption drastically. With the stock gears a tankfull didi not last much due to the high rpms needed to reach 65. Now is a breaze . I´m very hapy with the results.