By Cody Leigh, J&P RSC Tech, Rider and Mechanic for 10 years

How to set Mechanical Points:

Points serve as the mechanical ignition that tells the spark plugs when to fire. If the points are not set correctly you could have a range of problems with the bike such as too advanced or retarded ignition timing which will make the bike run very poorly and can cause damage to the engine. The bike may not even run as there will be no spark or too weak of a spark. Once points are set you will not have to adjust them again unless you remove them due to working on another part of the bike. If you have a weak spark or no spark, it may be because the contact point has worn down over time (this is usually about every two years or roughly 20,000 miles, but can vary by bike.) At this juncture, the points need to be replaced.

Tools required:

Multimeter

Phillips screwdriver

Cut-out pliers (These can be made by grinding out a pair of pliers so you can reach around the head of the bolt to grab the points cam)

Feeler Gauges

Warning! Disconnect the battery and do not leave the ignition on while setting the points as this will overheat and crack the coil and ruin it.

1. We must set the points gap before setting the timing. In order to do this we must first remove the points cover, exposing the mechanical advance and the points themselves. In this scenario I am setting the points on a 1972 Shovelhead motor, but this process is the same for setting all points.

Centering of cam lobes and setting point gap. (Pic 1)

·  Rotate the motor by lifting the rear tire and putting the bike in its highest gear and rotating the wheel. Remove the sparks plugs to make this easier. Watch the points cam for when the narrow end of the cam lobe is centered on the points contact pad (Pic 1).

·  Using the .020” feeler gauge, check the gap between the two contacts (Pic 1). If it is not .020” then you must adjust it accordingly by loosening the Phillips head screw and rotating the contact arm to set the proper gap.

·  After the gap is set, rotate the engine again until the wide end of the cam lobe is centered on the points contact pad. Check the gap with your feeler gauges. The gap should be within .018” and .022”. If it is not, you will need to adjust the contact arm again.

2. Now we will set the actual timing. To do this, the front cylinder must be on the compression stroke. To achieve this, simply undo and lift the pushrod covers to expose the pushrods so you can view them and remove the timing plug from the side of the crankcase.

·  Rotate the engine while watching the pushrods. Watch for the exhaust pushrod to go up and then down and then for the intake pushrod to go up and down. Once this has happened, you are on the compression stroke.

·  Now watch the flywheel through the timing hole and look for the timing marks to appear. If there are a total of three separate marks on the flywheel, then you will want to position the second mark inside the window. If there are only two marks on the flywheel you are going to want the first mark. (You will have to make sure you are on compression after you figure out which mark you need so you might have to rotate the engine a few times).

Multimeter connections and standoff screws. (Pic 2)

·  Patience and a steady hand is going to be vital here. Using the multimeter, set it to continuity or ohms and have the alarm or beeper on to where you can hear it. Connect the positive lead to the points arm itself (Pic 2) and the negative lead to a good ground (I use one of the bolts that holds the cam cover on). If the mulitmeter’s alarm isn’t on and the points are closed, then your leads are not hooked up properly.

·  Once the meter is hooked up properly you need to loosen the standoff screws (Pic 2). Do not remove. Using the cut-out pliers, rotate the cam to the full advanced position (towards the rear of the bike). Holding the cam at that point, rotate the entire points plate slowly till the narrow cam lobe is pressing against the points arm and stop as soon as the multimeter’s alarm stops, then tighten the standoff screws.

·  VERIFY! Leaving the multimeter hooked up, let the cam rotate back to its original position and then rotate it back to the advanced position slowly, watching to see that the alarm stops at the same time that the points arm makes contact with the cam lobe. If this isn’t correct, restart the timing process.

Once you have completed these steps I recommend that you trust but verify your work by checking the points gap again to ensure that you are within the guidelines set earlier. If you are not within the specifications it will affect your timing.