1988-1994 Honda TRX300 Fourtrax, 1988, 1990-1994 TRX300FW Fourtrax Service Manual, Page 221Get this manual
BRAKES Apply water to the whole of new waterproof sealPlace waterproof seal on clean surface plate, and press the brake drum into the waterproof seal, making sure that the clearances between the seal and drum will reach the calculated clearance (see previous page)
(1 BRAKE pRU M
CAUTION
Press the drum onto the seal evenly, so the lips will not be damagedIf the seal is damaged or mis-installed, remove it and try again with new seal(TRX300FW) Place steel plate [about 140 mm (5.5 in) in diameter and more than 10 mm (0.4 in) in thickness] on the brake drum, or the brake drum will be warped or damaged