How to Measure Whether a Motorcycle Igniter is Good or Bad?

[BrantleyFitz]

First, remove the spark plug for inspection. Under normal conditions, the spark plug gap should be between 0.5 and 0.7mm. Use the thickness of a small hacksaw blade to insert into the spark plug gap, and it should feel slightly stuck.

[Autumn]

I have some previous experience with motorcycle maintenance. The best way to test an ignition coil is using a multimeter. First remove the ignition coil from the bike and disconnect all connections to ensure safety. Set the multimeter to resistance mode and measure the primary winding resistance, which should normally be between 0.5 to 3 ohms - for example, my old bike measured around 1.8 ohms. Then test the secondary winding resistance, which should be approximately 5 to 15 kilo-ohms. If the values are significantly higher or lower, it indicates internal short circuit or open circuit issues. If there's no spark or only a weak yellowish spark, the ignition coil might be burnt out. Also check the high-voltage wires and connectors for aging or leakage, as this affects measurement accuracy. Safety first - wear insulated gloves to prevent electric shock. Common failures include aged coils, heat damage, or cracks from vibration. Regular maintenance can prevent problems.