950 stalling problem

Discussion in 'Dakar champion (950/990)' started by blownaway, Jun 3, 2004.

  1. blownaway

    blownaway Been here awhile

    Joined:
    Jan 21, 2004
    Oddometer:
    273
    My 950 has started cutting out at low revs for no apparent reason. :huh

    Yesterday after riding on forestry tracks and coming into a small
    town as I pulled the clutch in then it stalls dead. I then
    pull over and hit the starter and it fires up like nothing had
    happened.

    I running on premium gas.

    The bike seems to go OK and only stalls at low revs or at idle, today 3 times at 2 sets of traffic lights. If the bike is idling the engine seems to just stop but if it has a few revs as it is idling down and when I'm about to pull the clutch in for a stop it stalls. The problem is very intermittent making it
    harder to track down. Idle is set at about 1250 RPM and bike has only 2,500 miles on it.

    At the first 600 mile service the dealer told me the valves were in spec and no adjustment needed.

    This has only happened from about 1,800 miles onward; after I added the 16T sprocket.

    One recommendation I read from another 950 board was

    " I would suspect that the valves have tightened up. Mine were tight and needed new shims at 1000km. I broke it in pretty hard though. A lot of people have stated that valves didn't need adjustments at the 1000km tune. It is a bit unrealistic to think that the settings at the factory are going to continue to be good as the motor breaks in. Hell, it's one of the main reasons that they call it a breaking in period. Things are changing in the bike.

    So while your valves may have been fine at 1000km it is probable that now that you've been opening up the bike more and putting miles on it that they have really broken in"

    Has anyone else had this problem or any idea as to the cause?
    #1
  2. seh750

    seh750 Been here awhile

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    Oct 14, 2001
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    My bike stalls a bit too. Seemed to get better when I raised the clip on the needles in the carbs, but it still does it. I didn't think of the connection with the valves, but I'm in the midst of my 600-mile service and the valves are quite tight. I'll report after I complete the service and see how it runs, but it might be a couple of weeks.
    #2
  3. AntWare

    AntWare Lost In Translation

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    Mine started doing the same, there's another thread here that mentions the air mixture screw adjustments.

    I've raised my idle a little which fixed it for now but if it continues to worsen I'll re-balance the carbs.

    It could also have something to do with clutch drag, which appears to be another inherant quirk.
    #3
  4. Stephen

    Stephen Long timer Supporter

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    Feb 19, 2002
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    Austin, Texas, USA
    It's happened to me a few times, seems to happen when I come up to a stop in say third and let the revs drop too low while in gear. Not a good practice anyway and easy enough to avoid.

    I've also killed the poor beast letting out the clutch with little throttle turning the bike out of a parking spot when the coolant is still warm (four bars) but the engine isn't really warmed through. Again, my bad, I've done it on beemers and the KLR.

    Ironic, in a way, as otherwise the silver stallion rarely sees the south side of 4000 rpm. There's the lesson, reckon. Also, otherwise, the stone-stock and post-first-service engine works brilliantly.
    #4
  5. woodsrider

    woodsrider .........................

    Joined:
    Nov 22, 2003
    Oddometer:
    587
    Location:
    Colorful Colorado
    Mine does it too, seemingly on a random basis (but always while stopped or coming to a stop). It always starts right back up, however.
    #5
  6. kirkmoon

    kirkmoon Making up for lost youth

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    I have heard several 950 owners comment on the same thing. Mine does it too. The bike will be idling normally and then just....ping....stops. Starts right back up again. Very intermittent and quite infrequent. I would guess that it has happened maybe six or seven time to me in 8500 miles. On my bike, it has always occurred when idling and I am not sure about this but it seems to happen more often when I make a quick little blip on the throttle (but before the engine has a chance to repsond) than when I leave things alone. But I may be hallucinating on that last one.
    #6
  7. Jean-Luc

    Jean-Luc Throttle committed

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    Same for me. And it does that in neutral too which means that it's not related to my clutch dragging issue. One easy thing to do is to increase your idle to 1400 RPM as per the manual (instead of the 1250 you have now). That will not solve your issue but maybe save a couple of stall. KTMax mentioned that a CO level at 4.2% should be the cure.
    #7
  8. Lone Ranger

    Lone Ranger Been here awhile

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    Apr 22, 2004
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    Location:
    San Diego
    Mine is not doing it but I only have 1300 miles on it. When I rode a demo bike from one of the dealers before buying it stalled at every stoplight. I was not impressed. When I pointed out the problem to the mechanic he seemed to brush it off. I think the bike had 1800 miles on it.

    Keep us informed with what you find as it can be a real serious issue in low speed offroad situations
    #8
  9. darmahman

    darmahman "Illogically Deluded" Supporter

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    My understanding of the 1400 rpm idle speed is to make sure the cams are getting enough lubrication at idle. I had mine turned down when I got it new to around 1100 - 1200 rpms and at the 600 mile service the lobes were slightly scarred. Needless to say the idle is now always @ 1400 rpms.
    #9
  10. AntWare

    AntWare Lost In Translation

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    That's interesting, when I did the valves at 1000 miles, my rear cylinder exhaust cams were slightly scarred/discoloured.

    I was waiting to see if anybody else had come across it. You can see them to the right of this picture.

    I thought it unusual because the way the cylinder is canted the rear stays in an oil bath.

    [​IMG]
    #10
  11. darmahman

    darmahman "Illogically Deluded" Supporter

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    That is similar to what mine looked like. I will be checking them soon. I have 2000 miles on mine now.
    #11
  12. Goss

    Goss LC8 Adventurer

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    All of you guys that find their cams with scars be sure and share it here. That is something that needs to be addressed by KTM for sure. Don't want this to turn into a Ducati flaking rocker nightmare. Flaking rockers ? What flaking rockers.

    Goss
    #12
  13. merlin

    merlin Been here awhile

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    OK guys..... I've know what the problem is but everytime I try to help there alway seems to be somebody trying to shoot me down. The problem is in the air screw..... If you open the air screw up (turning it out) then your making it leaner. You should try turning it in about a half turn in from stock. I did it on my bike and it runs and idles cooler with no stalling. (I had the same problem as you).
    #13
  14. Mully

    Mully Kineticist

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    [​IMG]

    Since fuel and air are mixed before reaching the idle mixture screw, turning it in towards the stop leans the idle.

    mully
    #14
  15. Renegade6

    Renegade6 Been here awhile

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    Feb 23, 2004
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    New Boston, TX
    There was someone last week from NZ who posted about cams flaking.
    #15
  16. airheadbruce

    airheadbruce Uncle Dumbshit Supporter

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    Jan 19, 2004
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    If the screw is before the carb,(carb to air cleaner), adjusting it out leans the mixture cause it is an air bleed screw..this is usual on older carbs I've seen. If the screw is after the carb, towards the engine, it is a fuel screw and adjusting it out richens the mixture ...letting in more fuel.
    That is how I have understood it.
    #16