950SE running rich?

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by ToddLite, May 20, 2013.

  1. ToddLite

    ToddLite Been here awhile

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    So after a few rides on my new-to-me '07 950 SE I'm pretty sure the bike is running REALLY rich. Symptoms include:

    - able to start w/ little or no choke
    - ZERO popping on deceleration (never, not even once)
    - black crud at the exhaust
    - here's the kicker - I'm getting max 25-26mpg. Doesn't matter on/off road, easy highway cruising or tearing it up, whatever. 25-26mpg max.

    Bike seems to run great to me - no weird stalling or idle issues - with the exception that very rarely on a low gear hill climb or something I chop the throttle at the top it might seem to bobble and "almost" stall. After copious amounts of searching this forum it sounds like to improve the mpg I need to check/modify:

    - air filter isn't clogged/filthy
    - float heights (lower?)
    - needle heights, jet sizes, etc.

    I am far from a mechanic but reasonably handy so I was going to look into the carb configuration (with the assistance of a knowledgeable buddy). Any other recommendations prior to tearing into the carbs? easy things to check, etc?

    For the record, there have been a few diff exhaust configurations in its history. First stock then a 2-into-1 config and now it's been returned to a dual Wings exhaust with the "quiet end caps" in. PO claims he was getting 35mpg prior to selling it to me and is unaware of any re-jetting being done...

    Any other thoughts from the experts out there? I'd welcome them...
    #1
  2. Two Moto Kiwis

    Two Moto Kiwis Homeless Somewhere

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    Dirty filter is easy to see and a big cause or something stuck in the intake snorkel.

    Mixture screw settings will effect the bottom but more than likely jetting by the sounds of it.

    Also make sure the carbs are synced together or one may be working harder.
    #2
  3. David37

    David37 Been here awhile

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    I have an 07 KTM 950SE, like Twhiteside clean the air filter or better yet replace the air filter and replace the plugs while you have the bike apart. If you're still running rich, take off the carbs, clean and check what jet sizes are in your carbs.
    #3
  4. ToddLite

    ToddLite Been here awhile

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    Right on thanks guys that's what I figured... Thanks for the insights!!
    #4
  5. Afry

    Afry Why hike?

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    Huh?
    #5
  6. corndog67

    corndog67 Banned

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    Get it on a dyno and put a sniffer in the pipe. Hard numbers. No guessing.
    #6
  7. ToddLite

    ToddLite Been here awhile

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    I've actually thought about that but have never done that before... Have no idea how much something like costs or even where to go. Will certainly research and consider...
    #7
  8. corndog67

    corndog67 Banned

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    Well, at our local bike night, they put my Duc on there, one baseline run with sniffer, was $35 or $40. Cracked me up when "130 Cubic Inch, 130 HP, 130 lbs of torque" loud guy got called on the spot, dyno guy said, "Let's pull it and see..." and he agreed. It pulled 92 HP and 102 lbs of torque, my 916 pulled 95 HP and 67 lbs of torque, and the dude asked me how big it was, "900 ccs. Your bike just sucks, what is it, 2000 ccs?" He didn't like that.

    Seriously though, a sniffer on the dyno will tell volumes about how well tuned it is.
    #8
  9. TrentW

    TrentW MMmmmm....

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    It could be something as simple as the Choke cable(s) not seated properly in the carbs / junction box, thus the choke is partially on at all times.
    #9
  10. charlie264

    charlie264 Long timer

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    Howdy Trent....still got the SE?
    #10
  11. HooliKen

    HooliKen Awesome is a flavor

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    :lol3

    My thoughts exactly.

    Are you the original owner? If not did the PO do an jetting. I will second that you should check enrichment circuit on both carbs. And in lieu of running on dyno with sniffer, pull plugs, they will tell you volumes about how you are running
    #11
  12. triplenickel

    triplenickel Long timer

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    I wouldn't waste money on a dyno there's enough proven documented combos here, but figure out what you have now first after you check the basics.
    #12
  13. ToddLite

    ToddLite Been here awhile

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    sounds good guys - thanks for all insight. Jetting history is unknown at this point as the PO didn't do anything (and he was the 2nd owner) so getting a look at the current config is definitely a need. I'd like to start out with the simple stuff before really taking things apart... and for $40 or so bucks I'd be intrigued by the dyno/sniffer results. Will consider once I get a handle how it's currently configured...

    thanks again all
    #13
  14. TrentW

    TrentW MMmmmm....

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    Aye. It's soon to be winging it's way to NZ though... permanently. Can't wait... :clap
    #14
  15. Two Moto Kiwis

    Two Moto Kiwis Homeless Somewhere

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    May I ask, have you sold it to a Kiwi or are you moving there and if so where? there is only a handful in NZ now so adding one brings the percentages up quickly then we will bring ours home.
    #15
  16. ViperACR

    ViperACR Adventurer

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    I have an 08 and have the same issues 27 mpg and black crusty exhaust bobbles on mid- lower rpm roll on, and makes my back pack and jacket smell like I un-burnt fuel. My local KTM dealer was lost with it and said they returned it to stock jetting and charged me for no improvement. So took it to another KTM dealer and they have it running much better with re-jetting only. I haven't checked my mpg yet as I have been riding my HP2 for the last few weeks.
    #16
  17. TrentW

    TrentW MMmmmm....

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    We're moving back to Wellington (Johnsonville) - Yes, I can't imagine that there's too many over there - Looking forward to a few trail rides on it.
    #17
  18. Two Moto Kiwis

    Two Moto Kiwis Homeless Somewhere

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    Based on that welcome home!!!, there is only a handful in NZ so with yours and ours that is two more.
    #18
  19. ToddLite

    ToddLite Been here awhile

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    Just to give this thread a bit of closure for future inmates I finished my Head2wind jet upgrade last weekend and FINALLY got a chance to get a decent length ride in yesterday.... results are very satisfying as it looks like I'm getting about 35MPG now (instead of a solid 26-27mpg).

    Jetting in my '07 SE was surprisingly bone stock but the idle mixture screws were 2.75 turns out and I did have to "tweak" the float heights to somewhere between 3-3.5mm (they weren't super far off). After putting in the new jet kit, airfilter (mine was filthy dirty), prefilter and dialing back the IM screw to 1.75 it was way too lean (ton's of popping at idle and on decel). I bumped the IM screw to 2.5 and all is good. I have a feeling it's still maybe a tad rich down low with that 2.5 IM setting but at this point I've had my fill pulling carbs so i'm good for now.

    Bike seems to pull really smooth throughout the powerband now and I didn't notice it bogging down and nearly stalling after long low gear hill climbs when chopping the clutch/throttle at the top (like it used to...always a weird issue).

    So mission accomplished and I would highly recommend Ken's jet package for those with apparent jetting issues.
    #19