The Single Overhead Cam Four Owners Club

Tappet Adjustment Procedure

Added on by Glenn Stauffer.
  1. Remove the tank.
  2. Unscrew the tappet hole caps.
  3. When the No. 1 piston (pistons are numbered from left to right from the rider’s position (Fig. 1)) is at top-dead-center of the compression stroke.
  4. Remove the point cover and align the “T” (1.4) mark on the spark advancer to the timing mark (Fig. 2)
  5. Then check and adjust valve tappet clearances indicated by “0″ in the chart below.
  6. Measure the clearances using a feeler gauge, adjust by loosening the lock nut and turning the adjuster screw, and tighten the lock nut. (Fig. 3)
  7. Valve tappet clearances:
    INLET 0.05 mm (0. 002 in.)
    EXHAUST 0.08 mm (0. 003 in.)
  8. Next, rotate the crankshaft one revolution and realign the “T” (1.4) mark on the spark advancer to the timing mark (Fig 2)(in this position, the No. 4 piston is at top-dead-center of the compression stroke). Then check and adjust the valve tappet clearances indicated by ” X ” in the chart below. See item #5 above for proper valve tappet clearances.
    • Hold the adjusting screw so that it is not turned when tightening the lock nut.
    • Make sure the clearance is not disturbed when the lock nut is tightened.
  9. Cylinder Inlet Valve Exhaust Valve
    No. 1 O O
    No. 2 X O
    No. 3 O X
    * No. 4 X X