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Info Jetting for temperature & elevation

Discussion in 'Tech Tips' started by maelstrom, Jun 23, 2018.

  1. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

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    I know you have come here to find out what size big jets you can put in your bike to make it go faster, sorry to disappoint.

    http://www.hotrod.com/articles/hrdp-0406-density-altitude-tuning/
    I liked this part so much that I had to highlight it.

    "Otherwise, out in the field there are at least three real-world methods used by hot rodders and racers to dial-in a carburetor: reading the spark plugs; actual on-vehicle testing, beginning with deliberately rich calibration and gradually leaning the system out until performance falls off; and (in more recent times) tuning using the newly available wide-band oxygen sensors."

    This is the opposite of what motorcycle owners do. They increase jet size until their spark plugs are black enough to match the ones they have seen posted on the internet by like minded creatures. Then they can say "Yeah man, I'm running 180s with needles raised to the max".

    Now I just need to find the formula to show how much slower your bike will be when you fit that 180 section rear tyre that you have been drooling over to your 250.
    Cheers
    Blair
     
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  2. Frankster

    Frankster Grey Pride...Adventure before Dementia Staff Member Premium Member Ride and Events Crew

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    That's a good article. Cold, dry air with low barometric pressure...hmmm...naturally aspirated heaven!
     
  3. kiffsta

    kiffsta Senior Member

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    I had a very spirited convo with a customer who swore 125 mains in his cbr was going to give him 50 horses , but it’s true he said, it’s on the internet
     
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  4. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

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    Unleash the power! If only those stupid Japanese engineers knew how to do things right.
     
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