2002 Yamaha YFM660 Grizzly factory service and repair manual, Page 240Get this manual
MIDDLE GEAR
MEASURING THE MIDDLE GEAR BACKLASH 1.Measure: Gear lash Middle gear lash: 0.10.3 mm (0.0040.012 in) Measurement steps: Temporary install the right crankcaseWrap rag around screwdriver 3, and then insert it into the installation hole of the left crankcase speed sensor to hold the middle driven gear
the gear lash measurement tool and dial gauge 4Gear lash measurement tool: PNYM-01467, 90890-01467