Fitment questions?
Call (855) 786-7101 or text (801) 304-3141. We check fitment by VIN.
Product details
Black powder coating covers this left-front GP310 motorcycle caliper. It has four equal 1.25-inch stainless pistons in a billet body and uses the earlier 3.44-inch fork-leg mounting pattern. The documented application is the supported 1984–1999 Harley-Davidson front brake, subject to the stated fork and model exclusions. Based in Camarillo, California, Wilwood Engineering was founded by Bill Wood in 1977. The manufacturer produces disc brake systems and components for motorsport, street-performance and specialized applications, with a range covering calipers, brake rotors, master cylinders, valves, fittings and brake lines. Individual components are chosen to suit the complete brake system.
Technical Details
- Manufacturer part number: 120-7737-BK
- Caliper type: GP310 Motorcycle Front (1984-1999)
- Construction: Billet Aluminium
- Finish: Black Powder Coat
- Piston bores: 1.25 / 1.25 inches
- Piston type: Stainless
- Piston count: 4
- Published piston area: 2.46 square inches
- Dust boots: No
- Nominal rotor width: 0.25 inch
- Rotor thickness limits: 0.18–0.25 inches
- Rotor diameter limits: 11.00–11.50 inches
- Mounting style: Lug
- Mounting side: Left Hand
- Mounting centers: 3.44 inches
- Mount height: 2.33 inch
- Hydraulic inlet thread: 3/8-24
- Required pad shape: 6208
- Published pad area: 3.65 square inches
- Published pad volume: 0.63 cubic inches
- Manufacturer-listed component weight: 2.0 lb
- Supplied brake components: Individual GP310 caliper with brake pads
Fitment & Compatibility
Confirm the left side, original or replacement fork specification and rotor package before selection. An 11.00–11.50-inch rotor diameter envelope is listed for the exact caliper. Check the thickness limits and 3/8-24 inlet, and make sure pad and wheel clearance remain correct after the brake line is installed. Wilwood also specifically includes the 1983 Harley-Davidson XR1000 front application; verify the same fork, rotor and mounting requirements.
PMB Performance has over 20 years of experience helping customers with brake and parts fitment. Share the installed component identification and relevant measurements when requesting assistance.
Brake-pad warning: Cancer and Reproductive Harm. www.P65Warnings.ca.gov. This warning applies to the brake pads.
