if it was for an adult i would never put anything smaller than a 250cc in it either if i was swapping . a 125 barely has enough balls to haul the dirtbike frame around . its usuable power isnt made till 8000rpms, youd have no bottom end power and would be in misery trying to extraxt any torque out of thing not to mention itll fry the clutch in a days time and the gears are pretty weak for atv applications.its lack of lowend and midrange would make it pretty slow from point A to point B ,besides your not gonna get 35hp out of it like yo u would a modified blaster motor could potentially have.
