2005-2011 Honda Recon TRX250TE/TM service manual, Page 122Get this manual
CYLINDER HEADIVALVE
CYLINDER COMPRESSION
Warm up the engine to norm al operating temperatureStop the engine, disconnect the spark plug cap and remove the spark plugInstall the compression gauge with he gauge attachment into the spark plug holeShift the ransmission in neutral and open the choke lever (OFF)Open the throttle all the way and cra nk the engine with the starter motor until the gauge reading st ops risingThe maximum reading is usually reached withinsecondsCOMPRESSION PRESSURE:
1,275 kPa (13.0 kgflcm 2, 185 psi)
Check that there is no leakage at the gauge connection
low compression can be caused by: