ok i bought the xp upgraded all that was said to upgrade but it looks like i didnt have the motor and trans spaced properly, and it ground down the teeth on the spur gear, now im thinking, ive read alot of people seem to like the 2 speed but have also said it is alot more work, should i replace the transmission with a single speed? or should i stick with the 2 speed, if so what spur gears should i get? thanks for the help