Motorcycle Glossary
Ignition coil
In Turkish: Ateşleme bobini
In short
The ignition coil is a transformer that steps up the low voltage from the CDI or ECU to the many thousands of volts needed to fire the spark plug.
When the current in the coil's primary winding is cut suddenly, a very high voltage is induced in the secondary winding and carried to the spark plug through the HT lead and plug cap. Modern engines may use a "stick coil" that sits directly on the spark plug.
Symptoms of a problem
- A weak or yellow spark
- Misfiring in the rain or after washing (cracked body, damp cap)
- Cutting out at high revs
Plug caps and HT leads harden and crack with age, so check them together with the coil.
Also known as (including Turkish names)
- Bobin
- Buji bobini
- HT coil
Related products
CDI Units & Ignition Coils
Last updated: October 9, 2026
