1986-1989 Honda TRX250 FourTrax 250R Service Manual, Page 164Get this manual
REAR SUSPENSION SERVICING THE RESERVOIR The compression damping valve must be removed from the reservoir to drain the shock oilRemovethe screw from the center of the compression damping adjustment knob, then remove the knob, its two springs and detent balls(1) SCREW
(3) DETENT BALLS
Holdthe upper mount in avise with soft jaws or ashoptowel as shownUsingthe special tool, remove the compression damping valve from the reservoir; turn counterclockwise to removeTOOL: Valve wrench