1988-1994 Honda TRX300 Fourtrax, 1988, 1990-1994 TRX300FW Fourtrax Service Manual, Page 210Get this manual
BRAKES BRAKE BLEEDING
Connect bleed hose to the bleed valvePump up the system pressure with the lever until there are no air bubbles in the fluid flowing out of the master cylinder and lever resistance is felt
1Squeeze the brake lever, open the bleed valve 12 turn and
then close the valveNOTE Do not release the brake lever until the bleed valve has been closed
2Release the brake lever slowly and wait several seconds after it reaches the end of its travelRepeat steps and until bubbles cease to appear in the fluid coming out of the bleed valve