Vent Problem

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by marcel, Sep 18, 2005.

  1. marcel

    marcel Banned

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    This started after and oil change, When I would acc... hard 1 to 3 the bike would start poping and stalled. Mine is and 04 with the crap remove. I figured that a vent line was pinch to the frame rails, after three removale of the tanks, I couldn't find anything wrong with the vents and the problem was still present so I decided to blow some shop air in vent and voila the anoying promblem was gone. Has anyone seen this before with there 950?
    #1
  2. Flanny

    Flanny Flanny-it-up!

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    Sounds like your carburetor vents that are clogged with oil from the crank-case breather. Check your oil level - it may be too high...
    #2
  3. marcel

    marcel Banned

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    I forgot to mention this, the bike would only start after I open the tanks filler caps. And I could hear a pitch noise, so the tanks were not venting correctly, I figure some sort of crap was getting inside the vents line.
    #3
  4. marcel

    marcel Banned

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    Can and over fill cause this? It's one of the worse bike to get the proper oil level , when changing the oil , I'am only putting in 2.5L of oil and only re-check after 100km run.Ading maybe .25 of a liter.
    #4
  5. jsrider

    jsrider Long timer

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    In my experience if you follow the instructions in the owner's manual exactly, you will get exactly the right amount of oil in the bike after a change.
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  6. RAGrote

    RAGrote Long timer

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    Yes. If the vent line has a dip or rise in it (after the initial rise out of the tank) gas will trap there causing the bike to run like crap or not start at all. The problem doesn't show up until you try to open the throttle then the vacuum builds and the carbs starve.

    I have my vent end exposed so that I can blow through the lines in the event of a tip-over. Haven't had to use that option yet, however.

    I've seen the problem on a couple other toomers though....

    Make sure you don't have any "traps" in the run. After the line comes up and out of the tanks and starts it's downward path the line MUST continue down with no rises in it.
    #6
  7. marcel

    marcel Banned

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    I will exposed my lines also , thanks,
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  8. YOGOI

    YOGOI Prick

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    After the lines come up out of the tanks they should connect to a "T" connector under the head-light. Then I run a single vent line off of the "T" up as high as it can go (behind the instruments).

    If you run the single vent off the "T", DOWN or under the bike it can create a syphin effect and on real hot days you'll have gas pour'n out that vent line (I have seen this happen).
    #8
  9. RAGrote

    RAGrote Long timer

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    I've never had a problem. I think the syphon happens when gas gets trapped in a dip - when it starts to flow out of that dip a suction is created. I've never had an issue and have ridden on 90+ degree days on trails with the fan running non-stop.
    I think mine works because the gas never get's trapped along the run of the line.

    I'm gonna try your method but I had some problems when I tried this.

    c-ya
    #9
  10. YOGOI

    YOGOI Prick

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    The one prob. with the tanks venting into the dash is that you can get a strong wiff of the fumes from time to time.
    #10
  11. Pantah

    Pantah PJ Fan from Boston

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    Does anybody know if the carbs will work right if I vent both tanks to the atmosphere and just plug the two hoses running to the motor from the cannister?

    One of those two hoses seems to be a vacuum line because when I run the motor it sucks air. I have no clue what the other hose does.

    I unplugged the right tank vent and rode around awhile and didn't notice any difference. But those carbureters are pretty goofy working gizmos. I was thinking maybe they need those hoses to do something and if I plugged them or left them open, something bad might happen.

    Thanks in advance. -p
    #11