I'm running a 70 AC pump and was told a 50 is what I should be running.. I don't care about MPG just looking for the best jetting for making the most power. I'm running stage 1 with Andrews 21 cam

 

Anyone?

 

Just wondering...did you buy this carb new in kit form or used? The HSR 42 Easy Kit comes with an additional pilot and main jet as well as a smaller accelerator pump nozzle.

This is the information that is included with the Mikuni HSR 42 Easy Kit...


Twin Cam Optional Tuning
Suggestion: Certain Twin Cam 88/95 cubic inch configurations may improve fuel mileage by using our #20 pilot jet, #50 A/P nozzle and #2 needle clip position. These parts are now included. Refer to the HSR Tuning Manual (page 8-9) for detailed instructions.

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You can find PDF files on Mikuni's web site for the HSR 42 Easy Kits parts contents as well as the Tuning Manual.

I have an HSR 42 kit on the way and I'm running a TC/88 SE intake and exhaust with Andrews TW 21G's.

If you're running rich you are not making peak power from the carb and wasting fuel too. How does it run, does it seem lazy? Black smoke?

Tech23

 

Seems good to me. But not sure if there be added power if I add the 50

 

Anyone?

 

Never mind totally misread the question... Tossing more gas down a stock engine just won't make it faster. at a certain point you are just tossing gas out the back end.

 

I have a cam but it seems even guys with more work run the 50

 

To me that would suggest you're running too rich then. You have the same cam I have. It's not a high performance cam it doesn't have high lift or long duration. It's a bolt in cam. It's as close to the stock cam profile as you can get from Andrews. Put the suggested jetting in I posted above and see how it goes. I'm thinking it will run better and get better gas mileage too.

Tech23

 

I have the jetting u posted I'm just missing the 50 ac pump ill have to change it

 

The #50 should have come in the 42-18 carb kit. I asked this in my first reply....Did you buy the carb new in kit form or just a used carb?

Tech23