New set up , fine tuning

Discussion in 'Carb/Tuning' started by V4bandit, Jan 8, 2019.

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  1. Jan 8, 2019 #1

    V4bandit

    V4bandit

    V4bandit

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    Hey all! I just recently purchased the muscle jet kit from Sean. With reading every possible carb related thread with a bike near my elevation in Ontario, I've started with the following setup.
    155mains
    Pa1&2 stock
    Air corrector installed
    Stage7 needles, 3clip from blunt.
    Slides drilled
    Stock springs
    A/F @ 3 turns
    Float level set at 16mm dry
    Morley air box
    Dale Walker Holeshot exhaust

    Bike started right up. But had to run forever on choke, and occasionally puffing fire out the exhaust.
    Once warmed up seemed to run pretty decent.
    Synced the carbs and throttle response seems good. I'm unable to test ride until old man winter gives me a mild dry road day.
    Just wondering if there's anything I can do tuning wise on the lift, also what popping and fire out the exhaust means?

    Thanks
     
  2. Jan 8, 2019 #2

    one2dmax

    one2dmax

    one2dmax

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    Your float settings do have everything to do with the tune but sounds like you're where that needs to be. You can try to turn out the a/f mix screws a little bit and see if that improves it.
     
  3. Jan 8, 2019 #3

    caseyjones955

    caseyjones955

    caseyjones955

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    I sure dont know anything Sean doesnt, but I've read that stock springs and drilled slides do not play well together. I have no idea if that is the issue but it jumped out at me. I have the same jet kit and full exhaust, I think you will really like it. I hope you find the issue and get her sorted.
     
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  4. Jan 9, 2019 #4

    V4bandit

    V4bandit

    V4bandit

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    Thanks Sean! I forgot to say I originally had the a/f at 2.5 turns and it just idled down until snuffed out. I turned it to 3 and it idle ok, once warmed up.

    I guess I’ll have to wait patiently now. Woke up this am to fresh layering of snow on the ground
     
  5. Jan 9, 2019 #5

    Fire-medic

    Fire-medic

    Fire-medic

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    If Sean recommended 155 Mikuni mains, then that's a good place to start. Pretty-sure 152.5 is the USA stock jetting spec unless you're at some high-altitude.

    You could always try tying-back a few coils of the stock slide springs to shorten them. I'm not sure what is the length of the Stage 7 Dynojet springs, other-than they're shorter than stock. Maybe a couple inches? That' and the larger holes drilled in-place of the stock small base-of-slides holes, should make them react quicker than stock.
     
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  6. Jan 10, 2019 #6

    one2dmax

    one2dmax

    one2dmax

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    He may be a little fat with the 155's but each bike is different.
     
  7. Jan 10, 2019 #7

    Fire-medic

    Fire-medic

    Fire-medic

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    I've always heard, "better too-rich than too-lean," for engine longevity. Better safe than sorry.
     
  8. Jan 11, 2019 #8

    V4bandit

    V4bandit

    V4bandit

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    I was going to keep the 152.5 main, but my plugs are ghost white, and I seen a few others running 155’s, so I thought I’d try it.
    I really have no clue haha, going off trial and error
    I wish I could ride it to find out, damn snow!
     
  9. Jan 11, 2019 #9

    caseyjones955

    caseyjones955

    caseyjones955

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    It was suggested to me to try main jets until I found the ones that pull the hardest at WOT and tune down from there. It's monotonous but I found it effective. Seans jumping off point for me was very close on all settings.
     
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