TM40 Jetting for 5,000 Feet

Discussion in 'Thumpers' started by Hipster, Mar 14, 2005.

  1. Hipster

    Hipster Long timer

    Joined:
    Aug 31, 2004
    Oddometer:
    2,436
    Location:
    Mpls, Mn.
    KTM 640LC4 owners with Mikuni TM 40 carb riding at 5,000 foot elevation, what are you running for jetting?

    Next month I'm heading to Mexico and will be spending most of my time riding at 5,000 foot elevation. My setup for 800 foot elevation is;

    Pilot Jet: 17.5
    Pilot Air Jet: 1.1
    Pilot Screw: 1.5 Turns
    Needle: 9DJY4-98
    Needle Jet: Y6
    Needle Clip: 3rd From Top
    Main Jet: 157.5

    Will I need to change my setup to get the bike to start and ride well at 5,000 feet?

    Thank You,
    Tom
    #1
  2. Hipster

    Hipster Long timer

    Joined:
    Aug 31, 2004
    Oddometer:
    2,436
    Location:
    Mpls, Mn.
    Oops, the Needle Jet is a Y4 (not Y6).

    Tom
    #2