2001-2003 Honda TRX500FA Factory Service Manual, Page 190Get this manual
SUB-TRANSMISSION Turn the shift drum clockwise and set it in neutral position so that its groove position is lengt hw ise as shownInstall the shift forks into the gear shifter grooves and shift drum guide grooves with the marks facing outCoat the sh ift fork shaft with oil and insert it into the shift forks and crankcase
Inst all the output shaft into the crankcase and the output driven gear onto the shaft with the large raised side facing outInstall the rear crankcase cover (page 12-4}