Why does my FI bike have a choke plate? TE449/511

Discussion in 'EFI/carb' started by huskylove, Mar 24, 2014.

  1. robertaccio Husqvarna
    Pro Class

    Location:
    San Diego, Ca
    Husqvarna Motorcycle:
    2021 Husqvarna TE300i
    Other Motorcycles:
    99 HusqvarnaTE610, 94 Husaberg FC501
    Dangermouse449 likes this.
  2. Dangermouse449 Husqvarna
    Pro Class

    Location:
    Sunshine Coast QLD Australia
    Husqvarna Motorcycle:
    2011 TE449
    Other Motorcycles:
    2009 CRF450R 2000 YZ125

    You are right about the MAF being more cumbersome & dearer, I wasn't suggesting they should have fitted one, just that they are quicker to log changes of throttle opening.
    And yes, you get a much better 3D map for fueling/timing using the MAP rather than a TPS.
    A TPS-only system is a 'best guess' of the actual load on the engine, just knowing the throttle is open to 'x' position doesn't tell it how much air is coming in.
    So yeah, more dyno time to trim up the maps.
  3. Dangermouse449 Husqvarna
    Pro Class

    Location:
    Sunshine Coast QLD Australia
    Husqvarna Motorcycle:
    2011 TE449
    Other Motorcycles:
    2009 CRF450R 2000 YZ125
  4. huskylove Husqvarna
    Pro Class

    Location:
    norcal
    Husqvarna Motorcycle:
    1999 cr125 in progress
    Wow, that throttle body is "genius"...


    I want one! Lets send them a te511 throttle body to reverse engineer ;)
    Dangermouse449 likes this.
  5. Kyle Tarry Husqvarna
    Pro Class

    Location:
    Portland, OR
    Husqvarna Motorcycle:
    2012 WR 300, 2006 TE 610
    Other Motorcycles:
    Ducati Monster S2R 800
    That really depends on where the MAF is located. On many MAF cars, the MAF is out at the air filter, so the air pulse has to travel all the way from the filter to the valve, which takes time. MAP is measured right at the manifold (essentially at the valve), so it's near instantaneous. In this case, the MAP/TPS system is much quicker to respond.
  6. Tinken Husqvarna
    Pro Class

    Location:
    Hesperia, CA
    Husqvarna Motorcycle:
    MY12 WR511
    Other Motorcycles:
    Yamaha