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Latest post Tue, Aug 18 2015 9:47 PM by Ironhead. 1 replies.
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  • Tue, Aug 18 2015 3:05 PM

    • bojake
    • Top 500 Contributor
    • Joined on Wed, Sep 10 2014
    • Posts 78

    Keihen butterfly Carb

        I picked up an ebay carb a month or so ago and posted a few questions. After surfing the internet for al the info I could find on the carb ,I got it dialed in.

      Lots a guys say junk that Keihen and get an S&S. Sorry! Can't afford it! When you get a keihen butterfly carb tuned right, the heck with S&S. Out of the hole that keihen is quick as any. I'm satisfied.

      Anyway..I found the answers to my questions. You don't need the Oring for the intake flange. A paper gasket works. But..take a mill file and file a flat surface on both sides of the phenolic insulator block. (be sure to use a block so the cab doesn't overheat). I gaurantee it's not perfectly flat. And don't worry about covering up the little hole on the carb flange. It's nothing.

    Make sure both float adjustments are right on. My carb came with a 65 low jet and a 165 main. Prolly Sporty jetting. My Shovelhead ended up running best with an 80 low and 180 main. Fires up immediately.No Keihen carb farts or pops between gears or let off. I Titelocked the fast idle screw set with the end of the screw about a 1/4" from the stop. Manual says 6mm. The slow idle jet is set at about 1 5/8 turns. I had issues with the spring loaded valve needle that came with the fix kit. Hanging open and draing out the overflow.So I swapped the other one that came with the kit. Worked fine. 

    Andrews hi performance fuel regulators are available, but I really ain't needing it. Maybe down the road I'll try one.

    I have a Turbo air cleaner on the carb. Works great.

    I'm not missing the old S&S 2 throat at all.

    Oh Yeah!..Easy Riders #2 Tech tricks and fix manual has a great chapter on Keihen butterfly carb high peformance tuning. Which I found after the carb was already mounted. next time.



  • Tue, Aug 18 2015 9:47 PM In reply to

    • Ironhead
    • Top 10 Contributor
    • Joined on Tue, Mar 21 2006
    • Near Sunset at Sunset Beach, O'ahu, HI Oct 23, 15
    • Posts 2,670
    • Moderator

    Re: Keihen butterfly Carb

    thanks for the update - glad you got it working the way you wanted.

    The first tool out of the box should be the "book"  Geeked

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