55121 Compu-Fire Voltage regulator/rectifier. Black for Harley-Davidson
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Specifications
- Brand
- Compu-Fire
- Part Number
- 55121
- OEM Reference
- 74516-86
- Pack Quantity
- Each
- Category
- Regulators
- VAT Rate
- 20%
About This Product
This Compu-Fire voltage regulator and rectifier is a high-quality solid-state replacement for your charging system. Finished in black, this 22-amp unit features a 2-pin male connector for a straightforward installation. It is designed to meet or exceed original specifications, providing stable voltage control to protect your battery and electrical components. This regulator fits 1981 to 1988 Big Twin models and serves as a direct replacement for OEM part number 74516-86. It is an ideal choice for riders looking to restore the reliability of their early Evolution or late Shovelhead charging system with a modern, durable component that handles heat and vibration with ease.
Manufacturer part number: 55121.
Fitment
28 models81-88 Big Twin
FL Shovel 3 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 1981–1983 | Electra Glide FLH |
| Harley-Davidson | 1983 | Police FLH |
| Harley-Davidson | 1983–1984 | Touring Electra Glide Classic FLHTC |
FX Shovel 5 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 1983–1984 | FX Low Rider FXSB |
| Harley-Davidson | 1984 | FX Super Glide FXE |
| Harley-Davidson | 1981 | FX Super Glide Fat Bob FXEF |
| Harley-Davidson | 1981–1984 | FX Wide Glide FXWG |
| Harley-Davidson | 1981–1982 | Super Glide B80 FXB |
FXR 9 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 1985–1987 | FXR Custom FXRC |
| Harley-Davidson | 1982–1988 | FXR Low Glide FXRS |
| Harley-Davidson | 1988 | FXR Low Rider FXLR |
| Harley-Davidson | 1986–1988 | FXR Sport FXRS-SP |
| Harley-Davidson | 1983–1988 | FXR Super Glide FXR |
| Harley-Davidson | 1986 | FXR Touring FXRD |
| Harley-Davidson | 1984 | FXR Touring FXRDG |
| Harley-Davidson | 1983–1987 | FXR Touring FXRT |
| Harley-Davidson | 1984–1988 | Police Low Rider FXRP |
Softail 9 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 1983 | Dyna Glide Glide Custom FXDG |
| Harley-Davidson | 1985 | FX Low Rider FXSB |
| Harley-Davidson | 1985 | FX Super Glide Fat Bob FXEF |
| Harley-Davidson | 1985 | FX Wide Glide FXWG |
| Harley-Davidson | 1987–1988 | Softail Custom FXSTC |
| Harley-Davidson | 1988 | Softail Heritage Classic FLSTC |
| Harley-Davidson | 1986–1988 | Softail Heritage FLST |
| Harley-Davidson | 1988 | Softail Springer FXSTS |
| Harley-Davidson | 1984–1988 | Softail Standard FXST |
Touring 2 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 1987–1988 | Touring Electra Glide Classic FLHTC |
| Harley-Davidson | 1983 | Touring Tour Glide FLTD |
Planning other changes? Find your model in the bike customiser.
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Who are we? Leeds Harley-Davidson - Iron City Motorcycles
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