1999-2004 Honda TRX400EX FourTrax Service Manual, Page 189Get this manual
REAR WHEELlSUSPENSlON Install the driven sprocket with the chamfered side of the bolt holes facing inCoat new O-ring with oil and install driven sprocket flange and axleit
between the
Install the axle into the swingarm through the drive chain until it is fully seatedInstall the chain over the driven sprocket