990 ADV throttle bodies question

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by timbo45, Aug 27, 2013.

  1. timbo45

    timbo45 Been here awhile

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    Sep 4, 2010
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    174
    My brother said remove the butterflies. My friend Jeff spencer said put them back in . Do I need lock washers on these screws or blue locktight. I lost one screw so I replaced it with one like it .
    #1
  2. bikyto

    bikyto Dans le doute...gaz!

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    Jeff is right. After many hours testing various maps to improve the throttle response. The best configuration is with the butterflies. That said, I have oval ones since tuneecu did exist back then. Similar results can be achieved with just some time and perseverance.

    When I reinstalled mine, I opted for red locktight as I knew I would not remove them again. Not something you want to drop in the cylinder lol3
    #2
  3. renogeorge

    renogeorge Let's ride!!

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    Glad this thread was started. I have mine out but have been wondering if I should re install. I believe I read that they are operated by the stepper motors as directed by the ECU. I also think I read that they function below 5k RPM. I am wondering if they operate in response to something being measured by an O2 sensor or MAP sensor? Or do they follow some pre-programmed routine tied to the bikes emission testing/certification--with all the stock stuff?

    Is the consensus that they help IF you are changing pipes, using CPR intake, SAS removal etc.?

    Thanks
    #3
  4. Korruptio

    Korruptio Adventurer

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    Tip: Even if you don't have a TuneEcu cable, you can still download the software and some map files from the internet for free (http://www.tuneecu.com) and see by yourself what ECU is doing with injection, secondary flaps, ignition etc. It will make your thoughts about "how this engine gets it food and air" much more visualized than trying to figure it all out just by reading these endless threads in internet forums.
    #4
  5. renogeorge

    renogeorge Let's ride!!

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    I just got my cable and am learning the ropes with Tune ECU. Still would like to know more about the secondary butterflies and how they work....
    #5
  6. bikyto

    bikyto Dans le doute...gaz!

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    They are only affected by the input you give them in the map. Just like F1/F2, you can set them up to your specs.
    #6
  7. renogeorge

    renogeorge Let's ride!!

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    So, if the ECU is controlling the injectors and resulting air/fuel ratio, why would you want the second set of butterflies changing the mixture by adding or reducing air? And if the answer is-to meet emissions requirements, why would the secondary butterflies be needed when emission standards were not involved?

    Not trying to drag this out--just trying to get the best possible starting point for my tuning adventure.
    #7