2006-2014 Honda FourTrax ATV TRX250 EX TRX250X Service Manual, Page 207Get this manual
CRANKCASETRANSMISSIONCRANKSHAFT MAINSHAFT:
MAINSHAFT
M4GEAR BUSHING
Gear and bushing rotating surfaces, Mainshaft splines
M4 GEAR (23T)
(M1 GEAR; 13T) (M2 GEAR; 15T)
M3 GEAR (18T)