New motor fires up, on one cylinder

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by Qwik, Oct 12, 2012.

  1. Qwik

    Qwik Adrenaline Addict

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    trying to figure out why. put in different coil and plug to no effect. Front cylinder exhaust gets hot rear does not..any ideas?
    #1
  2. NKL

    NKL Been here awhile

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    Fuel in carb?
    #2
  3. TcRulz

    TcRulz Been here awhile

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    You could take the air cleaner cover off and pour a cap full of fuel in the rear carb throat and see if it fires on that:eek1 or might be safer to pull the rear coil stick and stick another known good spark plug in it (making sure its earthed) and see if it sparks:D. Has to be fuel, spark or compression all working at the right time. Good luck.
    #3
  4. NKL

    NKL Been here awhile

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    Just read the title again, what do you mean "new motor" and I assume nothing else has changed, carbs, electrics, ignition.
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  5. Qwik

    Qwik Adrenaline Addict

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    Replacement motor. Original electrics that worked fine with the old motor. Old carbs as well. Gonna try dumpin fuel down the carb and see if that works
    #5
  6. Head2Wind

    Head2Wind MotorcycleMayhem

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    Did you check the valve clearances and/or verify that the cams are installed correctly? If the seller is considered trustworthy, then this shouldn't be a issue if they were selling a known good running engine. But generally a good idea to verify and establish a baseline of known settings.

    Also, depending on how long the bike was apart for the engine transplant, the fuel may have fouled the jets or stuck the float. If there is no fuel in the float bowl, then the needle is stuck in the seat.
    #6
  7. bykpimp

    bykpimp Live and let ride

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    Verify you have spark in both cylinders, if so move along to fuel, compression, oxygen.............
    #7
  8. NKL

    NKL Been here awhile

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    Took the words out of my mouth.
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  9. Qwik

    Qwik Adrenaline Addict

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    Had a few minutes to mess with it today. Poured a little gas down the throat of the rear carb. Cranked it a bit and it coughed and fired on both cylinders. Gonna pull the carbs off and clean em up. Obviously some debris in the system that has it plugged up. It didnt sit long enough to gum up before I drained the Carbs.
    #9
  10. Dustodust

    Dustodust Long timer

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    it helps to run it with just the left tank on until you get it dialed , you can see what the carbs are doing and have access to them
    #10
  11. Qwik

    Qwik Adrenaline Addict

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    Yup. Only have the left Safari tank on. New carb clamp came in today as well. ( old one stripped but its on the front carb with a different screw/nut making it work.
    #11
  12. Narsisco Lopez

    Narsisco Lopez Addlepated

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    Carb? What's a carb????

    Oh! You mean those old-fashioned things my great-grandfather's Edsel used to have to shoot gas into the pistons! :lol3
    #12
  13. Qwik

    Qwik Adrenaline Addict

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    Doesn't shoot gas it drizzles it
    #13
  14. Qwik

    Qwik Adrenaline Addict

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    Tossed some sea foam in the tank to see if it will clean the jets/carb up a bit. It's poppin a bit and doesn't want to run off choke.
    #14
  15. TA-Zappa

    TA-Zappa Been here awhile

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    Exactly, the ones that doesn't give you whiplashes from normal use...

    :huh

    /Zappa
    #15
  16. Sumi

    Sumi Long timer

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    Sounds like you'll have to pull the carbs ( I know it's a pita ) and clean the jets one-by-one..

    No vac. leaks, right (intake boots, vacuum ports)?
    #16
  17. 68deluxe

    68deluxe Long timer

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    Yeah, those old-fashioned things that did not surge.
    #17
  18. GZERO

    GZERO Fixing stuff around

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    Your idle jets are plugged!
    But hey, is not something hard to repair.
    So dig in, and you'll got it running in no time.
    Have fun.
    #18
  19. Qwik

    Qwik Adrenaline Addict

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    Replaced the pilot(Thanks GZERO) jets with a set I had in my Jetting box and it fired right up and runs GREAT. I am no longer with out a Running KATOOM!!!!!!!!
    #19
  20. GZERO

    GZERO Fixing stuff around

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    You welcome!!
    now go out and powerslide that bike
    #20