Adjusting motorcycle valves is an owner's task. Doing it yourself will save you time and money without having to go to a mechanic. Some motorcycle models require valve adjustments more often than others. In any case, a systematic check of the condition of these parts will keep them in working order.
It is necessary
- - probe;
- - hex keys;
- - tools for adjusting screws.
Instructions
Step 1
Read your engine specification before proceeding with valve adjustments. It should indicate the characteristics of the gaps (usually measured in millimeters). It also contains information on how to adjust the top dead center of the piston. Look for the marks on the flywheel that indicate at what level the piston reaches top dead center.
Step 2
Remove the spark plug. Remove the bolts holding the valve cover and remove it. Be careful and hold the cover, on some models the bolts can be removed very easily. In some cases, the cover and the gasket underneath can get stuck in place, if this happens, use a rubber mallet to push it out of place. Install the engine piston at top dead center.
Step 3
Place a feeler gauge in the gap between the valve stem and the rocker arm (curved metal piece at the top of the valve). If the gap is correct, you will feel a little resistance on the dipstick. To adjust the clearance, loosen the lock nut and turn the adjusting screw a quarter turn.
Step 4
Continue adjusting until the correct clearance is obtained. When finished, tighten the lock nut while holding the adjusting screw. Avoid tightening the locknut too tightly, as the gap adjustment procedure may need to be repeated if retesting with the feeler gauge does not produce the desired result.
Step 5
Repeat this procedure for the remaining inlet and outlet valves. Most one- or two-cylinder engines allow the valve to be checked when the engine piston is at top dead center, however the adjustment procedure may differ. Be sure to check with your engine specification.
Step 6
After completing the adjustment, reinstall the valve cover. Keep the gasket and mating surfaces clean. Tighten the bolts crosswise, use anti-seize compound to avoid stripping the screw threads. Clean the spark plug and reinstall it.
