Compu-Fire
Representative Photo, actual item may vary
Compu-Fire 55522 32 Amp High Output Charging System for Harley-Davidson Twin Cam
Compu-Fire 53735 High-Performance Starter Motor 1.6kW for Harley-Davidson Big Twin
About Compu-Fire
Compu-Fire is an electrical performance brand best known for starters, charging systems and ignition components built for Harley-Davidson motorcycles. Founded in 1993, the company quickly became a leader in the Harley-Davidson aftermarket for performance ignitions, charging systems and high-torque starters. It later added ignition systems for air-cooled Volkswagens and expanded into high-output alternators and starters, including units for Honda Gold Wing touring bikes. In 2015, PerTronix acquired the Compu-Fire and Spyke brands, and Compu-Fire continues today as part of that family.
Why Electrical Upgrades Matter
Big V-Twin engines with high compression are demanding on a starting and charging system. A weak starter, a tired stator or a worn regulator can leave a rider stranded, and heavy accessory loads like auxiliary lighting and heated gear make the problem worse. Compu-Fire focuses on this part of the machine, offering stock-replacement and upgraded components that restore, and often improve on, original performance.
Starter Motors and Starter Components
Starting hardware is the heart of the lineup. The Compu-Fire starter motors include the Gen3 design, which the company says is engineered for cranking large-displacement, high-compression V-Twins without the need for compression releases. Compu-Fire also supports its starters with serviceable parts such as replacement solenoids, pinion gears and heavy-duty starter gear sets, so a worn drive can be refreshed without replacing the whole unit.
Charging System Components
A reliable charging system keeps the battery topped up at idle and under load. Compu-Fire's 3-phase charging systems, for example, are rated to provide 25 amps at idle and 40 amps continuously above 2800 RPM. Replacement parts let you service individual components rather than the whole system:
- Alternator rotors for rebuilding or replacing the spinning field element in a 3-phase charging setup.
- Alternator stators, where the charging current is generated, a common wear item on aging motorcycles.
- Voltage regulators that manage output to protect the battery and electronics from over- or under-charging.
Ignition and Beyond
Compu-Fire's ignition heritage remains part of the brand identity, with single- and dual-fire ignition modules, coils and plug wire sets designed to deliver a stronger, more consistent spark. Its Volkswagen line brings maintenance-free electronic ignition to air-cooled engines in place of points-based systems.
Shopping Tips
Always match parts to your model and year, since Harley-Davidson charging and starting systems changed considerably across the Evolution, Twin Cam and Sportster eras. Confirm whether your bike uses a single-phase or 3-phase charging system before choosing a rotor, stator or regulator, and consider replacing related wear items such as gears and solenoids at the same time as the starter.