Daelim S4 50cc Service Manual - Mojo

CYLINDER HEAD / VALVESVALVE GUIDEREAMERVALVE GUIDEINSPECTION● Insert the valve guide reamer from the combustionchamber side and ream the guide to remove anycarbon built-up before measuring the guide.NOTE•Take care to tilt or lean the reamer in the guidewhile reaming.•Rotate the reamer clockwise, nevercounterclockwise when inserting and removing.TOOL: VALVE GUIDE REAMER● Measure and record each valve guid inner diameter.SERVICE LIMIT: IN 5.04 MMEX 5.05MM● Measure the guide to stem clearance.SERVICE LIMIT: IN 0.075 MMEX 0.085 MM● Measure the inner diameter of the new valve guide.If the measure clearance is not within the servicelimit, replace the valve.VALVE GUIDEDRIVERREPLACEMENT● Heat the cylinder head to 130°C ~ 140°C.(270°F ~285°F).NOTE•Do not heat the cylinder head beyond 150°C(300°F).•Because there is burnt risk, do not unskifully work.•Do not heat locally by using of gas burner whengetting cylinder head warm.•When replacing valve guide, be sure to correctvalve seat.VALVE GUIDEDRIVER● Support the cylinder head and drive the old guidesout of the combustion chamber side of cylinderhead.NOTE•Avoid damaging the cylinder head when drivingthe valve guide out.● Install the new o-ring into the new valve guide.