42-18 Mikuni HSR Easy Kit-1990 to present Harley Davidson Evo & Twin Cam Models. For the maximum available increase in all round performance and power available, this kit will instantly impress.
Mikuni’s HSR Easy Kit dramatically improves the performance of Harley-Davidson’s new Twin Cam engine and delivers unmatched throttle response and acceleration! Used with a Screamin’ Eagle Air Filter and an aftermarket exhaust system like the optional Screamin’ Eagle Mufflers, the HSR42 Easy Kit adds 25% more horsepower to the output of Harley’s Twin Cam engines. In the 88 CUI motor, maximum horsepower is increased from 57.8 to 72.2 hp, and Max torque from 71.4 to 80.7 ft/lbs.
These kits are designed to work with your original Harley-Davidson intake manifold, choke cable, air cleaner and throttle cables. You can run S&S Shorty or other high performance air filters designed for the CV type carb. by using the special adapter included in the kit.
For the fitment of some versions of the S&S Shorty air-cleaner to a Mikuni HSR carburetor, the breather on the backing plate may need to have some material removed with some others requiring material to be ground off the outer edge of the S&S backing plate to allow for clearance giving total unimpeded movement of the return arm on the carburetor. See the picture showing this required modification.