F650GS to F800GS engine conversion ?

Discussion in 'Parallel Universe' started by diegoteck, Dec 7, 2012.

  1. diegoteck

    diegoteck Adventurer

    Joined:
    Oct 25, 2012
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    Can you "convert" a F650GS engine to be a F800Gs.

    They are both parallel twin 798cc but the F800gs output is 85hp vs 71on the F650gs.

    I'm sure more than 90% of the parts in both engines are exactly the same, but what is the difference.

    Anyone ???
    #1
  2. LukasM

    LukasM Long timer

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    Cams and throttle bodies are different, and the map on the ECU.

    The first two are easy and not that expensive, the third could be solved with a Power Commander, at least the fuel map, with slightly less aggressive timing. Since the stock mixture is too lean you could probably get more power out of it anyway.
    #2
  3. JGoody

    JGoody Been here awhile

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    Isn't the radiator bigger on the F800?
    #3
  4. pkbinder

    pkbinder Kissing Moose

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    Lukas, Have you done this conversion? Are you sure the ECU will cooperate? Paul
    #4
  5. vtbob

    vtbob wanderer

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    besides the cam and ecu difference the F800gs engine has air inject to burn the exceess fuel in the exhaust due to more cam overlap...all to meet the emissions requirement......

    also the need to burn h-itest gas. It is not clear to me that the f800gs engine running on regular has more power than the f650gs engine due to ECU compensating for anti knock.
    #5