1986-1989 Honda TRX250 FourTrax 250R Service Manual, Page 36Get this manual
MtINTENANCE Set the turn gauge under the front wheelsMeasure the casterCASTER: '86, '87: After '87: 440' Canber and caster are not adjustableIf they are out of specification, check the suspension and frame for damage and replace any parts necessary, then recheck alignment
CYLINDER COMPRESSION
Warm up the engine Sto the engine and remove the spark plugRemove the fuel tank (page 3-3)Install compression gaugePush the choke idle speed knob down to the closed positionFully open the throttleOpE,rate the kick starter pedal several timesNOT Watch for compression leaking at the gauge connectionJ soap solution is useful for th is