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MIKUNI HSR45 SMOOTHBORE CARBURETOR KIT

MIKUNI HSR45 SMOOTHBORE CARBURETOR KIT

MIKUNI HSR42 SMOOTHBORE CARBURETOR

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S&S SUPER-E AND SUPER-G CARBURETOR KITS

S&S SUPER-E AND SUPER-G CARBURETOR KITS

Mikuni's Research and Development Department has spent many months to improve the HS carburetor series to meet all the street riders performance needs. First step was a larger body to fill the need for bigger throttle bores in all-out performance applications; step two had to be a smoother and easier throttle operation. This resulted in the design of the HSR42 carburetor. A major feature of the HSR42 is the flat throttle slide assembly with roller bearings. Unlike butterfly throttle valves, which obstruct the carburetor's venturi at all throttle openings, creating airflow turbulence and hindering precise air/fuel metering, the flat throttle slide allows an unobstructed venturi at full throttle, thus flowing more air and carbureting more precisely at all throttle settings. The roller bearings on throttle slide provide a light throttle action, which offers smoother control and allows the use of a very light throttle-return spring. With its 42mm venturi, the HSR42 flows 20% more air than the HS40, making the HSR42 an ideal carburetor for Evolution Big Twin and Twin Cam engines employing other performance modifications such as big bore kits, cams, pistons and an exhaust system (Mikuni still recommends the smaller HS40 carburetor for stock and mild tuned Evolution Sportsters). Flow bench tests by Jerry Branch show that the HSR42 Mikuni, while still being smaller in venturi size to some other popular carburetors, is able to flow more air to the engine once installed on the manifold and head. The HSR42 Mikuni actually flows more air at full throttle to produce more peak power. At partial throttle openings, the Mikuni's smaller, yet higher velocity flowing venturi, together with its advanced fuel-metering system provides a stronger overall powerband with improved ridability. Other performance features of the HSR42 include a larger capacity float bowl and a higher flowing needle-valve assembly to accommodate extended full throttle operation. Also, more positive action of the high leverage float valve prevents the possibility of the float bowl over filling or the needle-valve flooding. This eliminates the need for overflow and vent tubes on the carburetor body, giving the carburetor a cleaner look. An adjustable accelerator pump provides instant throttle response throughout the RPM range. Kits work with 1990 thru 2017 style Big Twin throttle and idle cables. Other features are instant engine response, improved rider throttle control, more mid range power for faster acceleration and passing with more confidence, good gas mileage and years of dependable service. Installation instructions and hardware are included with each kit. Mikuni developed several kits for special applications as well as "Easy Kits" that use stock manifolds, choke cable, air cleaner and throttle cable.

Throttle and idle cables for use with Mikuni HSR42, and HSR45 carburetors Early style HSR42 and HSR45 carburetors have the cable wheel on the left side of the carburetor and use cables as in the table above. Late style HSR42 and HSR45 carburetors have the cable wheel on the right side of the carburetor and use 1990 or later OEM style cables as used on Big Twin models. Most cables are available in black vinyl or braided steel.


Instructions

Specifications

Total Kit, fits Evolution Big Twin models 1984-1999, except 1984 thru 1988 FLH and FLT.
All 1984-1989 models require the seperate purchase of mounting flanges ZPN 234039 & 234040 and seals ZPN 740343
Includes performance intake manifold, rubber mounting flange, HSR42 carburetor, high flow K&N filter, Chrome air cleaner cover, breather kit and hardware. Uses stock style 1990-2017 Big Twin throttle and idle cables.
Article number Description Retail price Add to cart
720448
Total Kit £762.32
731452
Total Kit, approved £791.50

Total Kit, fits Twin Cam models 1999-2005

Includes performance intake manifold, rubber mounting flange, HSR42 carburetor, high flow K&N filter, Chrome air cleaner cover, breather kit and hardware. Uses stock throttle and idle cables.

Article number Description Retail price Add to cart
720542
Total Kit for Twin Cam £812.97

Easy Kit, uses stock manifolds, choke cable, air cleaner and throttle cable

Easy Kit for 1200 Sportster models 1994-2006
Includes HSR42 carburetor, special backing plate and hardware. Use the stock oval cover and a high flow replacement filter.
Note:
Use in combination with same year stock style Big Twin throttle cables. These must be ordered separately

Article number Description Retail price Add to cart
720447
Easy Kit for 1200 Sportster £533.09
Easy Kit for Evolution Big Twin models 1990 thru 1999
Includes HSR42 carburetor, air cleaner adapter and chrome cover. Uses stock style cables.
Note:
Does not work with cruise control.
Article number Description Retail price Add to cart
720445
Easy Kit for Evolution Big Twin £533.09
731451
Easy Kit for Evolution Big Twin, approved £562.27
Easy Kit for Twin Cam models
Includes HSR42 carburetor, air cleaner adapter for Screamin' Eagle filter, and instructions. Use with stock style throttle cables and air cleaner cover. Will not work with stock air box or cruise control.
Article number Description Retail price Add to cart
720446
Easy Kit for Twin Cam £479.78
Economy Kit
Includes 42mm HRS carburetor and air cleaner adaptor to install a 1990 to present style air cleaner. Uses 1990 thru 1995 stock style cables.
Article number Description Retail price Add to cart
234852
Economy Kit £471.15
731453
Economy Kit, approved for Evolution Big Twin FXR, Dyna and Softail models £500.33
720451
Mikuni HSR42 carburetor only £442.47
Early style throttle cables (pull)
Article number Description Retail price Add to cart
114557
Black cable, stock length thru 1995 £16.39
114561
Black cable, +4" thru 1995 £14.36
114559
Black cable, +6" thru 1995 £18.43
722894
Braided steel, clear coated, stock length, thru 1995 £91.54
232264
Black cable, stock length 1996 to present £45.77
232006
Black cable, Buell 1997 to present £98.56
722893
Braided steel, clear coated, stock length, 1996 to present £91.54
760407
Clear Coated, +6" 1996 to present £109.02
Early style idle cables (push)
Article number Description Retail price Add to cart
114558
Black cable, stock length thru 1995 £13.46
114562
Black cable, +4" thru 1995 £17.60
114560
Black cable, +6" thru 1995 £18.61
722896
Braided steel, clear coated, stock length, thru 1995 £91.54
232265
Black cable, stock length 1996 to present £45.77
232007
Black vinyl, Buell 1997 to present £98.56
722895
Braided steel, clear coated, stock length, 1996 to present £91.54
760408
Clear coated cable, +6" 1996 to present £106.29
Replacement parts
Article number Description Retail price Add to cart
236047
Manifold for Evolution £97.75
236049
Manifold for Twin Cam £97.75
237960
Air filter element £167.98
232600
Chrome air cleaner cover £85.55
232601
Chrome air cleaner cover with cutouts £82.49
234861
Rebuild kit, includes needle valve assembly, top cover gasket, spigot body seal, float bowl seal, rubber boot for accelerator rod, and O-rings £54.84
741712
Fuel screw washer £1.48
741713
Fuel screw O-ring £1.52
237958
Rubber carburetor-to-manifold mounting flange for early style manifold with round opening £39.70
236048
Rubber carburetor-to-manifold mounting flange for late style manifold with oval opening £39.70

Recommended Retail Prices include 20.00% sales tax.

Prices exclude shipping, import duties and installation.

Prices are based on EUR to GBP interbank rates obtained daily. The interbank rate is the rate that banks trade currency to each other. These prices must be used as a guide.