High Altitude KTM 950 Jetting!

Discussion in 'The Rockies – It's all downhill from here...' started by Yellow Pig, Jul 18, 2007.

  1. Yellow Pig

    Yellow Pig Allergic to asphalt!

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    Hello Coloradoans,

    All those who have a 950 and have played with the jetting, what setting have you found work best?

    I'm still running the stock set up wick is OK, but I can tell I'm running rich.

    I'd like to tweak it a bit. Any input is welcome.

    Thanks Dan
    #1
  2. 309

    309 Special Purpose

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    :lurk
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  3. The Fist

    The Fist Knulp

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    Inquiring minds want to know -- I'm running rich too...I was just about to post the same question.
    #3
  4. Infracaninophile

    Infracaninophile Finding My Way..

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    Paging Neduro to the white jetting phone. White jetting phone... :ear

    t.
    #4
  5. 309

    309 Special Purpose

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    FWIW, I already asked Ned and Wayne Weber for jetting specs.

    Wayne: "Stock jetting and needle position, 2 turns out on the fuel screw. Or more, or less, a bit richer than stock."

    Ned: "155, 68, 42 is what's written on my whiteboard... :dunno"

    My bike has FMF's, and a full cannisterectomy and SAS removal. I have everything stock, but went a 1/4 turn richer on the fuel screws. I am currently experiencing two flat spots in the powerband at about 5k and 8k, and am getting a bit of surging at steady throttle.

    I just had the bike serviced, and the flat spots seem to have appeared with the service. The surging has been apparent for a while. I am going to look for a pinched hose..

    What's odd is that the symptoms my bike is having seem to be indicative of a lean condition that would be fixed by raising the needle. This is what I've gleaned from reading the endless jetting threads in Orange Crush. However, I've also got a bit of soot on the ends of the mufflers, and have been told that there is a gas smell behind me...

    I'm going to look for a pinched hose and see if that makes a difference. If not, I'm going to try raising the needles a clip and leaning the fuel screws by a half a turn. I'll report the results here.

    This would all be so much simpler if it didn't take so long to get to the carbs. Two hours per change makes chasing a jetting problem a real pain in the ass.
    #5
  6. Hayduke

    Hayduke ///SAFETY THIRD/// Super Moderator

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    I helped Sonny (HP2 Beater) re-jet his 950 Adventure when he was here a couple of months ago. His bike has Akropovic's and a canesterectomy.... We went one jet leaner on both carbs and left the fuel screws alone. He reported much better performance here at 7,000' :dunno
    #6
  7. 309

    309 Special Purpose

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    On the mains or pilots?

    Was it stock before?
    #7
  8. arroyo

    arroyo ??????????

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    are you sure it's the bike??
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  9. 309

    309 Special Purpose

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    Boy, I lobbed that one to you, didn't I?


    It was Forrest who said it. I think it was his upper lip.
    #9
  10. unaweep

    unaweep Uses lotsa band-aids

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    Dan- I have my SE set up with no SAS, Cannister gone, raised needles from the fourth slot up to the second. Haven't touched the screws yet. It runs real well up to 10,000. After 10,500, it's hard to start and doesn't idle well, but runs in the mid and top end just fine. I'm interested in refining my settings as well. I may move the needles down to the middle notch and adjust the air screws to see if I can smooth it out.
    #10
  11. Hair

    Hair Free to a good home.

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    I might as well get my name in the hat on this thread.
    #11
  12. Hayduke

    Hayduke ///SAFETY THIRD/// Super Moderator

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    sorry. Only changed the mains. I believe it was stock jetting before.

    FWIW, getting to the carbs on the 950 was easy. Compared to my V4's. :baldy
    #12
  13. Beemer Pat

    Beemer Pat ...

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    #13
  14. DakarNick

    DakarNick Swabee

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    I'm with you 309. I have a few flat spots that showed up after my canisterectomy and SAS removal. The ends of my stock pipes seem to be ok, though I haven't really checked if they're sooty.

    I need to pinpoint where the flat spots are, seems like 3rd gear about 4500 rpm.

    Guys, after the emissions removal won't the bike be running leaner since the air that was going to the cats is now staying in the engine to be burned?

    Nick
    #14
  15. Lomax

    Lomax Nanu-Nanu Adventurer

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    I don't know what was done to mine but I believe it was one size down on the mains and needles in second notch. I had Roger up at Elite do it with the initial service. Pollution crap gone and Akrapovic slip ons. It runs great I guess :D

    Marc
    #15
  16. RKeeble

    RKeeble Adventurer

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    I'm running with this setup and it's good for me:

    Akrapovics
    158/160 mains
    42 idle jets
    2 turns out
    70 idle air jets
    FactoryPro needle @ /2

    It is slightly lean at idle when it is colder, but with the recent heat wave it's been good so I haven't yet bothered to adjust the idle screws.

    I haven't noticed any flat spots.

    Denver altitude.

    Gas mileage is forty-something per gallon when cruising.

    The mains could probably go a skootch leaner.

    -Rob
    #16
  17. AntWare

    AntWare Lost In Translation

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    Fella's, one thing I haven't seen mentioned is the different jets front/rear.
    Stock jetting is 155 front, 160 rear, so if you want to go leaner swap the front to the rear and drop a 150 in the front,

    ...and put the money you save in your tyre fund
    #17
  18. Hayduke

    Hayduke ///SAFETY THIRD/// Super Moderator

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    oooohhhh yeah......That's what we did to HP2Beater's bike..... Now I remember!
    #18
  19. DakarNick

    DakarNick Swabee

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    I posted this, can anyone comment on it or am I totally wrong? :ear
    #19
  20. Hayduke

    Hayduke ///SAFETY THIRD/// Super Moderator

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    You're right. I think at higher elevations, it needs to be leaner still, though.
    #20