2007 KTM 990 S Lc8 Engine Mods

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by BikeBandit, Apr 4, 2008.

  1. BikeBandit

    BikeBandit Adventurer

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    I was wandering if anyone has done any major performance mods to their Lc8 engine, more than just removing the SAS system and re-mapping of computer? Mods such as working with the cams, bore, valves, serious engine re-build type of stuff for increasing horsepower.

    I can't help it, I 'm never happy with the standard factory set-ups, conscidering I intend on racing this beast. :clap
    #1
  2. gweaver

    gweaver NorCal is Best Cal!

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    I haven't done anything personally, but I've heard that the cams from the 990 Super Duke are a direct replacement. I think the SD puts out a few more horsepower, so a cam swap might help out.

    G
    #2
  3. BikeBandit

    BikeBandit Adventurer

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    Thanks Gweaver I'll look into it.
    #3
  4. cpmodem

    cpmodem Orange Caveman

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    You may also need the SD heads to go with the SD cams. They are a different part than the ADV.
    #4
  5. str

    str Adventurer

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    Sry for hijacking the thread a bit but read in a swedish forum about a mod where you disconnect two cables on the 990 and when you do this the limit on 2 and 3 gear is removed. I tried search but translating the swedish technical terms to english don´t work for me. So help is needed :-)
    #5
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  6. byker_tr

    byker_tr Fenabahce

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    Fenerbahce Cumhuriyeti , Bursa - TURKIYE
    #6
  7. str

    str Adventurer

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    #7
  8. pauloston

    pauloston Adventurer

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    I'm putting together a 1090cc stroker for my SE ATM, if anyone's interested...
    #8
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  9. catalina38

    catalina38 Long timer

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    I didn't think the SAS removal was considered a performance/power upgrade.
    #9
  10. uk_mouse

    uk_mouse Aquatic adventurer

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    It's not really, it's just removing supurfluous hoses :)

    Although someone did suggest, when you remove the SAS, leave the left hand exhaust port vent attached, and connect the crankcase breather hose to it. Obviously plug up the hole in the top of the airbox. This will lower the air pressure in the crankcase giving less resistance to the movement of the pistons and allegedly increase power :D

    It's also a way of preventing the oil that comes up the breather from ending up in your front carb.
    #10
  11. tahoeacr

    tahoeacr Long timer

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    If you are still sporting the 07 then 07 Superduke cams will drop right in.
    [​IMG]
    red is stock cams
    green is SD cams/some airbox mods/DNA filter
    blue is custom 2-1 exhaust


    [​IMG]

    This graph quality sucks but all of these runs were strictly airbox changes
    [​IMG]

    Since your in Aus. and I here KTM parts are pricey down there you might want to check in to WEB cam in Los Angeles. They have cams for the SD but I don't know if they will fit without cutting reliefs. Superduke R heads have bigger valves and flow better.
    Airbox gets heat soak and is too restrictive. Insulating will drop 50+ degrees off of Intake Air Temps.
    Lots of gains can be had in the exhaust.
    Wouldn't be hard to get 30+hp. KTM engineer has told me the engine was designed for 145 reliable hp.
    #11
  12. they

    they bewilderness

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    Uh yeah. Weld and grind, billet or what? Bore too?
    #12
  13. 990s

    990s Adventurer

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    Mr tahoeacr:

    First sorry about my English! (This is my first post to!)
    I was wondering about a sd cam swap on my 06 990, could you enlight me about what needs to be done with the FI mapping, or do the "selflearning" EFI adjust fuel/air ratio and (possibly ignition) itself ?

    And
    Does the motor needs to go out for cam swapping?

    Are you happy with the modification?

    More information on the airbox modification? :evil

    990s
    #13
  14. Dan950ser

    Dan950ser Two Wheeled Addict

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    Sorry to hijack but will SD cams fit in a SE. Seems worth it for 10 extra ponies. Oh and please more info on the 1090cc stroker. Thanks
    #14
  15. mousitsas

    mousitsas Long timer

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    +1090 :ear
    #15
  16. pauloston

    pauloston Adventurer

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    Ok, here it is...
    STD 950 Se Motor is 100 x 60

    Mine will be 105 x 62.4

    Custom made forged pistons, HC
    Crankshaft from 990 (62.4 stroke)
    40mm Titanium Inlet Valves
    Heads ported and flowed
    Balanced and lightened bottom end
    990 SD R Camshafts

    I have 2 spare pistons if anyone's interested.

    A lot of people ask me "why?"

    I did a RTW on this SE, Cape Town to Magadan. The bike was throwaway by the end, so it's having a rebirth. So, while it's apart, "why not!"

    Attached Files:

    #16
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  17. gixxersteph

    gixxersteph Been here awhile

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    This is cool. Cannot wait to see your progress Paul. I presume that the second set of pistons were bought to pursuade the manufacturer to produce them in the first place.
    :clap:clap
    #17
  18. viola-tor

    viola-tor Needs to ride!

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    I'll be keeping an eye on this thread. I too have an '07 adv., want more power. Thinking about the SD cams and I'm planning on trying my hand and FI maps this season. Already have the Ned 2-into-1 and FMF can.

    30+ HP!?!? Yes PLEASE!!! (with the disclaimer that I'm on a KLR-ish budget)
    #18
  19. pauloston

    pauloston Adventurer

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    Well, I expected a bit more interest from this, for the few of you that are interested, its done.

    It's a stonking motor that makes me laugh in the helmet a lot...

    IMG_0294.jpg
    #19
  20. pauloston

    pauloston Adventurer

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    1080 se r

    Attached Files:

    #20