How to Set the Timing on Shovelhead Pointsby Tracy Underwood
The term "Shovelhead" refers to a Harley-Davidson Big-Twin engine that was produced from circa 1966 to 1984. The first generation Shovelhead from 1966 through 1969 was actually the same engine as the Panhead engine that it replaced, except for the updated cylinder heads. All Shovelheads came from the factory with a standard breaker points ignition until the 1978 model year. While the later capacitive-discharge electronic ignition systems produce more top-end horsepower, the original points system is simple and reliable. One of its advantages is that even a neophyte can easily set the timing statically while the engine is not running.
Remove the spark plugs, the timing port plug (on the left side of the engine case between the cylinders) and the timing cover (on the right side of the engine case).
Place your thumb over the front-cylinder spark plug hole and kick the engine over slowly with the kick starter. Stop when you feel pressure on your thumb. This indicates that the front piston is approaching TDC (top dead center) of the compression stroke.
Look in the timing port and continue to slowly kick over the engine until the advance mark (vertical line) is centered in the port.
Connect the red lead of the test lamp to the negative coil terminal, and the black lead to a good ground. Turn on the ignition switch.
Sit on the ground facing the timing mechanism. Loosen the timing plate screws.
Reach into the timing mechanism and grasp the point cam, which is in the center of the mechanism. Twist the point cam counterclockwise until it stops. Hold it in that position while you move the points plate (the round plate that the points are mounted on) counterclockwise until the test lamp lights.
Turn the points plate slowly clockwise while holding the points cam counterclockwise. Stop as soon as the test lamp goes out. Tighten the timing plate screws to lock the adjustment.
Turn off the ignition switch. Replace the timing cover, timing port plug and spark plugs.
- The timing mechanism on model year 1969 and earlier bikes rotates clockwise, which is the opposite of later bikes. Thus on 1969 and earlier bikes you would twist the point cam clockwise and turn the point plate counterclockwise.
- Do not use the round dot mark to set the timing. If you see the round dot (TDC), you have turned the engine too far.
Items you will need
- Service manual
- Timing test lamp
- Spark plug wrench
- 3/8 inch hex wrench
- Flat-blade screwdriver
- "How To Repair And Maintain American V-Twin Motorcycles"; Sara Liberte et al; 2006
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