1. TM42-6, HSR 42mm Mikuni Carburetor, Natural or Polished/Chrome

$540.00 AUD$695.00 AUD


Only the chrome and polished version comes with a choke cable supplied

The Mikuni TM42-6 , HSR42 is supplied with the following factory jetting installed:

Pilot jet 25 (VM28/486),  Needle 8DDY1-97,  Needle Jet Y-6 (723 Series),  Main Jet 160 (N100.604),  Air Jet 0.0 Blank,  Slide Cutaway 3.0 (TM42/08),  Needle valve 4.2 (786-27001)

Dimension A= 46.5mm, B= 90mm, C= 176mm, D= 65mm, Total Width 100mm

Going fast has never been so easy. The number one performance carburettor flows 213 CFM, 17 CFM more than the TM40-6 and delivers around a 25% improvement in performance and power over stock carbs.

This carburetor can be adapted to a number of different applications where space allows.

On Harleys they use the original throttle cables. Mikuni’s Big Twin and Sportster/Buell Easy Kits fit the bike’s existing manifold, choke cable and air filter. The air-cleaner Adaptor HS42/001 and O-ring HS42/003 will need to be purchased separately to fit OEM CV and S&S air-cleaners to these carbs.

In other applications where some modifications are required for fitting, any effort and time spent is soon forgotten once you experience the better throttle response, improved acceleration, increased power and torque. Mikuni’s smoothbore, flatslide with roller bearings, and accelerator pump technology delivers peak performance from idle to Wide Open Throttle.

These carburetors are available in the standard natural finish or for show bikes and some Harley Davidson owners there’s the chrome and polished version.

NOTE:  The polished and Chrome version comes with a choke cable which is not included in the TM42-6 natural finish, which will use most stock cables from CV type carb Keihen and Mikuni carbs.

The in carb jetting is suitable for twins with a 900cc and bigger engine capacity whilst just purchasing one size up and one size down in the main jets to be able to fine tune the top end would be an adequate starting point. But for fitment to big singles does require the replacement of nearly all the jets to perform properly so the requirement of purchasing a tuner kit from our tuner kit listing is essential. This carb delivers exceptional performance improvements on any 4-stroke single engine over 600cc and on any 900 or bigger twin that they will physically fit to.

Compare your existing carbs dimensions against the A, B and D  above for direct replacement compatibility and study the pictures taken on our graph board (the black lines are at 10mm spacings with 1mm increments in between), to determine available space if fitting in an unpublicized application.

With an unmatched air-cleaner spigot diameter or carb length and if still wanting to use the OEM air box rather than a Pod, check out our “Air-cleaner adapter listing”. If you can’t find a match, the manufacturing of special sleeves or extensions for some applications may be necessary. This is easily done by your local machine shop or any muffler shop with a pipe expander and the results far surpass the inconvenience.

If your OEM cables don’t match and if not available in our “Throttle and Cable assembly list”, you may well also need to have yours modified or new ones made for your application.

(The picture with the cables for applications other than ’89 and later Harley Davidsons shows the required length of inner cable protrusion and securing fitting at the carb end on basically a minimum length adjustment. The back board is divided into 1 and 10mm increments)

All international buyers are responsible for the payment of their domestic customs duties and taxes charged on imported goods. The duty free threshold and duty/taxes payable rates differ from one country to another and we strongly advise you check your liability before ordering if unsure. Please check your tracking on all international shipments within 7 days to follow their progress and determine if it is being held by your local customs dept. or on their behalf by the Postal Service, who you will need to make contact with using the provided tracking number.

Please Note: Other than exact replacement OEM carburetors, all Mikuni Aftermarket Carburetors and Tuning Components are sold “As Is” for Off Road / Racing Use Only and are not intended or approved for use on vehicles operated on Public Roads or in locations where applicable engine tampering and anti-pollution laws apply.


Additional information

Purchase Options

Natural Finish, Polished & Chrome


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