Protorque Hitachi Style Starter For Harley 1974-1988
Protorque Hitachi Style Starter: High-Torque Power for Classic V-Twins
The Protorque Hitachi Style High-Torque Starter is the definitive electrical upgrade for vintage Harley-Davidson riders. Designed to replace the aging and often underpowered factory units used between 1974 and 1988, this starter brings modern 1.4 kW power to the Shovelhead and early Evolution platforms. If your bike struggles to turn over when hot or stalls against high-compression pistons, this Protorque unit provides the mechanical muscle needed for crisp, reliable starts every time.
Powerful 1.4 kW Performance
Most original Hitachi starters featured a modest 0.8 kW output, which can struggle with performance cams or big-bore kits. The Protorque assembly boasts a 1.4 kW motor, delivering up to 50% more cranking torque and higher shaft speeds. This ensures that your engine reaches the required RPM for ignition faster, putting less strain on your battery and reducing the wear on your starter drive and ring gear.
Heavy-Duty Internal Construction
Engineered for longevity, the Protorque Hitachi-style starter is manufactured using heavy-duty armature commutators and oversized bearings. It features high-quality needle bearings in the end caps to reduce friction and heat buildup during long cranking cycles. Unlike cheap reproductions, these units are individually tested to ensure they meet or exceed OEM performance standards before they leave the factory.
Authentic Fitment and Design
This starter is specifically designed for models originally equipped with a Hitachi-brand starter (easily identified by its 5-1/4″ body length). It is a direct “plug-and-play” replacement for OEM Part Number 31570-73. Housed in a compact 80mm diameter casing, it maintains the classic “short model” look of your vintage Harley while hiding a modern, high-output motor inside.
Fitment and Compatibility (1974–1988)
The Protorque Hitachi Style Starter is designed for the following applications:
- Harley Big Twin FX Series (1974–1986): Super Glide, Low Rider, Wide Glide.
- Harley Big Twin FL Series (1982–1984): Electra Glide models.
- Harley Touring & FXR (1984–1988): FLT and early Evolution FXR models.
- Harley Sportster XL (1974–Early 1976): Ironhead models equipped with Hitachi starters.
- Note: Not interchangeable with the 6″ long Prestolite-style starters. Uses 10-24 mounting bolts.
Protorque Hitachi Style Starter For Harley
Features:
12 Volt Hitachi Style High Torque Starter
Guaranteed to Meet or Exceed OEM Performance
Unit Contains Heavy Duty Armature and Oversized Bearings
Replaces OEM 31570-73 T
Note: For models originally equipped with a Hitachi Starter, identified by 5 1/4″ length as opposed to the 6″ Prestolite starter.
| Product Style | AmericanV-twin Item # | Catalog Number | Store Sku | MFR. Product # | Availability |
|---|---|---|---|---|---|
| Black | 18142 | 803-652 | 4397 | PH125-HD10-B | In Stock: Ships within 24 hours |
| Chrome | 18143 | 803-653 | 4398 | PH125-HD10-C | Only 6 Left: Ships within 24 hours |
This Product Fits
Harley Davidson
Electra Glide Classic FLHC 1981, 1982
Electra Glide Classic FLHTC/I 1983-1988
Electra Glide Special FLHX 1984
Electra Glide Sport FLHS 1981-1988
Electra Glide Standard FLHT/I 1983-1988
Low Glide/Low Rider FXRS 1982
Low Rider Belt FXSB 1982
Low Rider FXS 1977, 1978, 1981, 1982
Softail Custom FXSTC/I 1986-1992
Softail Heritage Classic FLSTC/I 1987, 1988
Softail Heritage FLST/I 1987, 1988
Softail Springer FXSTS/I 1988
Softail Standard FXST/I 1984, 1985, 1986, 1987, 1988
Sturgis FXB 1980, 1981, 1982
Super Glide FX 1974-1979
Super Glide FXE 1974-1985
Super Glide FXR 1986, 1987, 1988
Super Glide II FXR 1982, 1983
Tour Glide Classic FLTC/I 1983-1988
Tour Glide FLT 1984, 1985, 1986
Wide Glide FXWG 1980-1986
XLH1000 1974, 1975, 1976
