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Latest post Sun, Jul 15 2018 10:44 AM by Nevada Dave. 2 replies.
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  • Mon, Jun 11 2018 5:23 AM

    Carburetor Issues on 2003 HD Dyna Low Rider

    Hello.  Have a question...when I push choke in, bike backfires through the carburetor.  When I have choke all 1/4 way out, she runs fine.  Just wondering, why this would be? Also, wondering if it hurts the bike in anyway, to run with the choke 1/4 of the way out, at all times?  Thanks!

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  • Mon, Jun 11 2018 6:35 AM In reply to

    • FX
    • Top 10 Contributor
    • Joined on Sun, Mar 12 2006
    • Tonawanda NY
    • Posts 5,210
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    Re: Carburetor Issues on 2003 HD Dyna Low Rider

    skeezix, the engine is running too lean. If you haven't changed the exhaust or carb then I would look for a vacuum leak in the intake...It won't hurt running with choke partly on for a while. However, It may foul the spark plugs...


    Don't force it, get a bigger hammer.

  • Sun, Jul 15 2018 10:44 AM In reply to

    Re: Carburetor Issues on 2003 HD Dyna Low Rider

    Slow jet is clogged or the low speed circuit is clogged. Had the same thing happen to mine after it sat for a year and the gas went bad. I had to totally disassemble the carb and clean all the jets and needles - everything. When I put it back together it ran fine. 

    Technically it's not a choke but an enrichener. Chokes imede airflow. The enrichener adds fuel. Both tend to do the same thing, but approach it from different directions. That's why it runs with the "choke" out - it's getting fuel from that enrichener circuit. When you push the knob in, it closes off that circuit and the slow-speed circuit is supposed to take over. In your case it doesn't. That is the problem. 

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