Compufire 40A 3-Phase Charging System - Vented Rotor Harley Evolution & Big Twin
About Compufire
Compufire parts and accessories are stocked at Vtwinbikers for Harley-Davidson and Indian Motorcycle applications. Every Compufire item we list is new and sourced through authorized distribution. If you are not certain a part matches your year and model, use Shop by Bike or email our team before you order and we will confirm fitment first.
Keep your Harley Evolution or Big Twin powered up with the Compufire 40A 3-Phase Charging System. This robust system is engineered to provide consistent, high-output charging, essential for running modern accessories and maintaining battery health on older bikes.
Why riders pick this
- High output: 25A idle, 40A above 2800 rpm
- Vented rotor for superior heat dissipation
- Maintains 14.25V with high-output regulator
- Designed for OEM primary compatibility
- Made in the USA for quality assurance
The Compufire 40A 3-Phase Charging System is a direct upgrade for 1981-1999 Harley-Davidson Big Twin and Evolution models. It's designed to deliver strong charging performance, producing 25 amps at idle and ramping up to a full 40 amps above 2,800 rpm. The key feature is its vented rotor, which actively dissipates heat, ensuring the stator runs cooler and maintains optimal output even during extended rides or heavy electrical loads.
Consistent Power and Enhanced Durability
- Delivers 25 amps at idle and 40 amps above 2800 rpm
- Vented rotor design significantly improves heat dissipation
- High-output voltage regulator maintains 14.25V from idle
- Narrow rotor and stator profile designed for OEM primary compatibility
- Made in the USA for reliable quality
Reliable Power for Your Classic Harley
This Compufire charging system is an ideal solution for riders looking to improve the electrical reliability of their 1981-1999 Harley-Davidson Softail, Dyna, or FLT models. The narrow profile of the rotor and stator ensures a direct fit with OEM primary cases, simplifying installation. Investing in a high-quality charging system like this means more consistent power for your lights, ignition, and any added accessories, preventing common electrical issues on the road.
Specifications
- Brand: Compufire
- Manufacturer Part #: 55560
- UPC: 694342548056
- Length: 9 in
- Width: 8 in
- Height: 8 in
- Weight: 11 lbs
Common questions
What Harley models and years does this charging system fit?
This Compufire 40A 3-phase charging system is designed for 1981-1999 Harley-Davidson Big Twin and Evolution models, including Softail, Dyna, and FLT chassis with OEM primary cases.
What is the amperage output of this system?
This system produces 25 amps at idle and ramps up to 40 amps above 2,800 rpm, providing ample power for your motorcycle's electrical needs.
Does this system require any modifications to my primary case?
No, the narrow rotor and stator profile of this Compufire system are specifically designed for direct compatibility with OEM primary cases, making it a straightforward replacement.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | Compufire |
| TYPE | Electrical |
| SKU | 139-10021 |
| WEIGHT | 11.0 lb |
