Setting Ironhead Points

Kevin is getting close to wrapping up the service of his 1977 Sportster. Now he will be addressing Ironhead points. After adding fresh motor oil and a replacement oil filter, Kevin gives one more inspection of everything front to back on each side of the motorcycle.

This Sportster’s ignition has never been updated to an electronic ignition. It is still running mechanical Ironhead points ignition. This is fine because, when set up and maintained correctly, points ignition systems work incredibly well.

Iornhead points are a mechanical ignition that tells the coil (spark plugs) when to fire. It is critical that points gap and timing is correctly set. If Ironhead points are not correctly set, the result can be a number of different problems. The motorcycle may run very poorly or not run at all. Incorrect spark or timing can severely damage a motor.

To set points gap, begin by removing the spark plugs and raising the rear wheel off of the ground or table lift. Shift the transmission into high gear so that the motor can be turned over by rotating the rear wheel. Remove the timing cover and timing cover gasket.

Now, turn the rear wheel while watching for the narrow cam lobe to be centered on the Ironhead points contact pad. Use a .018″ feeler gauge to check or set the gap between the contact points. If the gap is not correct, it should be adjusted by loosening the locking screw and rotating the contact arm until .018″ gap is achieved.

After the narrow lobe gap is set, rotate the motor until the wide lobe is centered over the points contact patch. Use feeler gauges to check this gap. Correct wide lobe gap should fall between. 016″ to .020″. If the wide lobe gap needs adjustment, it is very important that the narrow lobe gap is rechecked.

It is important to practice patience when setting Ironhead points gap. An accurate gap setting may take a few attempts before you are happy with your adjustment. Especially if you are setting points gap for the 1st time.

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