Mikuni HSR Series 42/45/48mm Smooth Bore Carburetor Kits

HSR Carbs use stock H-D® throttle cables. The latest 42/45/48mm smoothbore carbs install quickly using the original stock throttle cables. The HSR flatslide carb delivers excellent throttle response and improved rider control. The smoothbore allows the engine to reach its full power potential, so you accelerate and pass with confidence. You’ll get good gas mileage and many years of dependable, carefree performance. These kits cover more models with fewer part numbers. Kits include instructions and hardware for each application.

Total Kits

These Kits are complete with everything needed for a total installation. Kits include an HSR 42mm or 45mm carburetor, new performance manifold, rubber flange, high flow K&N filter, chrome cover, breather kit, and mounting hardware. Stock throttle cables from 1990 & later models can be used. NOTE: 1984 thru 1989 Evolution® models will need new cables from a similar 1990 thru 1995 model. SOLD AS KIT

HSR42 Kits
#42-153 Fits 1340cc Big Twin Evolution® models 1984 thru 1999.
Includes breather kit for 1993 & later models.
NOTE: 1984 thru 1989 models require cables from 1990 thru 1995 models.
#42-252 Fits Twin Cam® 88/95 1999 & later. Includes new breather kit for
Twin Cams®. NOTE: Use your stock throttle cables.

HSR45 Kits
#42-253 Fits 1340cc Big Twin Evolution® models 1984 thru 1999. Includes a 45mm big bore carburetor, breather kit and a 45mm flange.
#42-254 Same kit as above part No. 42-253 except without intake manifold.
#42-255 Fits Twin Cam® 95 1999 & later. Includes a 45mm big bore carburetor, breather kit, new manifold with MAPS location and a 45mm flange.

Easy Kits

These e kits are designed to work with your original H-D® intake manifold, choke cable, air cleaner and throttle cables. You can run other high performance air filters designed for the CV type carb by using the special adapter included in the kit.

#42-152 Fits Big Twin 1340cc Evolution® models 1990 thru 1999 with stock CV type manifold. Includes 42mm carb, airbox adapter, and chrome cover.
#42-156 Fits Big Twin 1990 thru 1999 and Twin Cam® 1999 & later. Includes 42mm carb, airbox adapter and instructions. Evolution® uses Screamin’ Eagle® air cleaner, Twin Cam® uses the stock oval cover.
#42-250 Fits Sportster® 1200 1994 thru 2002. Includes 42mm carb with special
airbox back plate. Requires the use of the stock oval cover and a Screamin’ Eagle® high flow replacement filter.
#42-251 Fits Sportster® 1200 models and Buell , 1994 thru 2002.
Must use with aftermarket performance air filter.

48mm race KITS for big inch motors

Designed for the serious race engine builder & extreme street motor enthusiast looking for more power. recommended for 120 C.I. engines or bigger with high flow heads & cams kits include a 48mm smoothbore carb, rubber mounting flange (78mm bolt hole centers), choke cable, and four main jets. Builder supplies manifold and appropriate air filter or velocity stack. Use stock CV type cables. SOLD AS KIT

#42-256 HSR48 race kit, standard cast alloy body, cadmium fittings.
#42-257 HSR48 race kit, hand polished cast alloy body, chrome fittings

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