2006 suddenly stalls once warmed - idle mixture?

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by motoracer51, May 13, 2012.

  1. motoracer51

    motoracer51 Been here awhile

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    Sep 18, 2009
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    662
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    Western Colorado
    Bought the bike used with about 18K miles on the odo a few months ago. I noticed that once it began to get into the warmer temps the bike would stall randomly, once warm, when idling - usually on coasting to stop lights/signs. It's usually takes a few seconds on the starter to re-fire.

    I'm thinking it's the idle mixture too lean? What do you guys think?

    This is really bugging me as I love the bike, but this stalling is making it a pain to enjoy. I would love to take the bike on some linger trips but refuse to until I rectify this stalling.

    Thanks for any help
    #1
  2. dad2bike

    dad2bike Cranky Old Fart

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    I suggest you get familiar with your carbs. May be time for some cleaning and possible float adjustments.
    You could run some cleaner thru your next tank of fuel to see if that helps first.
    One of the best additions I did for mine was the remote mixture screws to allow me to adjust on the road. :D
    #2
  3. motoracer51

    motoracer51 Been here awhile

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    Just curious - Is it an air or fuel mixture screw on these bikes? Hopefully I can tackle it today.
    #3
  4. Pete156

    Pete156 I love to eat!

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    Make sure your idle is above 1400 RPM. (Just my $.02 worth)
    #4
  5. motoracer51

    motoracer51 Been here awhile

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    Yeah, it's at about 1500. When I tried to increase it a bit higher, it would stop stalling, but it would then have trouble coming back down. It would stay around 2K and then settle to say 1800.
    #5
  6. motoracer51

    motoracer51 Been here awhile

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    Rear was 3.5 turns out, and the front was 2 turns out. Is this because the rear runs hotter, thus running leaner?

    Also, what would you do - 1/4 turn richer? 1/2 turn?

    Thanks
    #6
  7. dad2bike

    dad2bike Cranky Old Fart

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    You really need to look at all your jets to understand why the PO did that. I suggest finding out what all your jets are so you know where you are to know where you need to go. ;)
    Your pilot jets should be the same. Typically a 42 or a 45. The mixture screws should be about the same. I've never had them more than an 1/8 turn different.
    Typical starting point for the mixture screws is 1.75 or 2 turns both.
    #7
  8. motoracer51

    motoracer51 Been here awhile

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    Well, I took the thing apart and noticed that A. There was MASSIVE soot build up on the canisters:
    [​IMG]
    Also seemed like the intake tract of the rear cylinder has a decent amount of carbon build up on it.

    I ended up leaning out the mixture on the rear 3/4 turn, and on the front 1/2 turn. Started it up and brought it up to temp and it seemed to be running SWEET. I wont know 100% till I take it out for a ride sometime this week.
    #8
  9. Head2Wind

    Head2Wind MotorcycleMayhem

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    Was the bike ever tuned for the aftermarket exhaust and/or for your elevation prior to you purchasing it?

    anything greater than 2.0 IMS turns usually means that someone has been changing things. I usually run the IMS the same front/rear on these engines, however it may be necessary on some to get them to fuel correctly.
    #9
  10. motoracer51

    motoracer51 Been here awhile

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    Western Colorado

    I know that the guy that traded it into the dealer lived out here in the same valley - so the altitude should be the same. Not sure if the PO did the exhaust install, or if it was tuned by someone else.

    I'm going to try to ride it some this week and see how she goes. I'd like to take it to Salt Lake City for the World Superbike races in 2 weeks.
    #10
  11. motoracer51

    motoracer51 Been here awhile

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    662
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    Just an update.

    I finally was able to ride the bike with the new idle mixture adjustments and it still stalls out - perhaps even more so. I'm thinking I went the wrong way?

    What a PITA to get to the carbs on this thing.

    I know about the fuel pump issues - do any of you guys think it might be that?

    Thanks
    #11