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Home » Topics » CARB Tuning

CARB Tuning

Home › Forums › Parts & Technical Info › CARB Tuning

  • This topic has 1 reply, 2 voices, and was last updated 9 years, 10 months ago by Kevin Chopper.
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  • July 21, 2015 at 3:02 pm #3320

    @sittn-duck
    Subscriber

    Update: the 032 intermediate jet did the trick. Once it is warmed up it runs smooth. It pops a lot and loudly through the exhust when I let off the throttle and am slowing down in gear but it runs good otherwise. I took it out on the freeway and ran it at 65 in 5th gear and at 75 in 6th gear for 92 miles and am getting 40 mpg so I am done with the carb…I never expected it to do that good.

    My Raider came out of Texas back to it’s CA home.
    I have fixed all the little things,Starter, master Cylinders, Brake lights, Gas Cap, so now I figured it is time to attack the spitt’n and sputter n going on when holding a steady throttle at say…45 or 50 mph.
    It is running a 078 Main and was running a0295 intermediate jet.
    I increased the Intermediate to a 031 but it is still pulsing, not smooth and steady. When I open it up and it gets on the main jet it runs very smooth and steady, not a single miss. so I figure the ignition system, Plugs and wires are good.
    Things did improve a lot when I put in the 031. But not completely fixed.
    So I put in a 032 tonight and will try it tomorrow. I checked the intake for leaks by spraying but got no change in rpm, so that check was ok. How high on the Intermediate should I go before going to the next size main jet. I know they work together.
    Thanks

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    July 23, 2015 at 10:27 pm #3321

    @chopnoh10
    Subscriber

    Jetting is determined by intake and exhaust, how much air gets in and how it flows out. Baffles in the exhaust hold back pressure on the exh. valve giving more lower end torque as you reach the power band. Popping or back fire while backing off throttle is a sign of exhaust leak near the exhaust pipe meets the cylinder head, air is leaking in the pipe and lighting the unburnt gasses, change your exhaust gaskets and torque the pipes at the head before clamping or tightening rear pipe mounts. The best way to rejet is on a dyno with a master tech. Good luck! B)

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