Results 1 to 11 of 11

Thread: Throttle sticking open on hills

  1. #1
    Join Date
    9th December 2005 - 20:11
    Bike
    Several old ones
    Location
    Waikato
    Posts
    750

    Throttle sticking open on hills

    My KDX 200 has a habit of the throttle sticking on steep up hill climbs, this happened in Taupo recently and almost caused me to crash.
    I thought it may be dirt in the carburettor slide but it appears all clean except for the top of the slide where it appears the a little dirt has dropped into it from the inside of the throttle cable, I have now cleaned this out but dont know if it will fix it.
    This will only happen, like once in every 3 hours riding?? beats me.
    the cable is not pinched anywhere, the throttle snaps shut very quickly, so not binding the petrol tank is clean.
    The throttle appears to stick at near full revs , which as can imagine, can give you a fright.
    The jets are all clean as is the bowl.
    Anyone had this happen, or can offer any good advice it would be appreciated

  2. #2
    Join Date
    22nd April 2005 - 21:18
    Bike
    2009 Husqvarna SM610ie
    Location
    Zork
    Posts
    1,725
    Have you checked the throttle slide for damage?

  3. #3
    Join Date
    10th June 2005 - 21:17
    Bike
    None
    Location
    Waitara
    Posts
    805
    see if the needle is tight in the slide (or resonably firm)needle could be coming out of alignment and leaving the throttle jamed wide open

  4. #4
    Join Date
    13th January 2004 - 11:00
    Bike
    Honda PC800
    Location
    Henderson -auckland
    Posts
    14,163
    Take your twist grip assembily to bits.Dirt inside can jam things up OR there might be a bit of damage to the grip or the bar tip.
    Do you have barkbusters? Maybee when the throttle is opened up to a certain point the tube is rubbing and jamming on the barkbuster
    To see a life newly created.To watch it grow and prosper. Isn't that the greatest gift a human being can be given?

  5. #5
    Join Date
    10th June 2005 - 21:17
    Bike
    None
    Location
    Waitara
    Posts
    805
    He said the throttle snaps shut quickily so rules that out....

  6. #6
    Join Date
    3rd February 2004 - 08:11
    Bike
    2021 Street Triple RS, 2008 KLR650
    Location
    Wallaceville, Upper hutt
    Posts
    5,227
    Blog Entries
    5
    If the carb snaps shut - is this with the engine running or stopped?
    If the slide is worn, when there is no intake manifold vacuum the slide will move up and down fine, but when running under a high load condition (ie hill climbing, wide open throttle) it's possible vacuum is pulling the slide against the side of the carb bodyand it sticks. Are there any wear marks on either the slide or the sides of the hole? How old is the carb?
    Somewhere I've seen references to air flow through the carb at WOT being enough to hold the slide up but can't find it.
    Last edited by pete376403; 21st January 2008 at 22:34. Reason: addition
    it's not a bad thing till you throw a KLR into the mix.
    those cheap ass bitches can do anything with ductape.
    (PostalDave on ADVrider)

  7. #7
    Join Date
    29th October 2007 - 18:48
    Bike
    SOLD, looking for a new one.
    Location
    Hamilton
    Posts
    343
    far, stuff that. would scare the shit out of me!!

    good luck finding a solution though!
    My choice is what I choose to do,
    And if I'm causing no harm, it shouldn't bother you.

  8. #8
    Join Date
    25th March 2004 - 17:22
    Bike
    RZ496/Street 765RS/GasGas/ etc etc
    Location
    Wellington. . ok the hutt
    Posts
    21,234
    Blog Entries
    2
    PWK slides wear in these with a grin line when they are at idle, but this could cause an issue at higher openings esp as Pete says. The price of a new one will make you sit down but it does help Carburetion throughout. Erm mine 7 yrs ago was like $187. Maybe it was $87, but I think the former. But a full throttle crash could cost you more than that & you'd still have to fix it - if you were up to riding it again.

    I would also remove the slide & try the throttle itself if slightly over extended does it hang up esp if there is sideways force on it?
    Don't you look at my accountant.
    He's the only one I've got.

  9. #9
    Join Date
    7th December 2007 - 12:09
    Bike
    Valkyrie 1500 ,HD softail, BMW r1150r
    Location
    New Plymouth
    Posts
    2,144
    This may sound stupid, but with the cable being a bit to lose,I have had cable itself on full throttle go outside its guide on carb body and thus stay open, no matter what you do with throttle.... worth a quick check...( maybe combined with some pull on whole cable in certain conditions....
    good luck
    Opinions are like arseholes: Everybody has got one, but that doesn't mean you got to air it in public all the time....

  10. #10
    Join Date
    9th December 2005 - 20:11
    Bike
    Several old ones
    Location
    Waikato
    Posts
    750
    Thanks for these items of advice guys, very interesting, I firstly thought it was grit getting sucked bythe air filter somehow and causing the slide to stick. But the filter is clean, so is the carby side of the filter intakes.
    I have cleaned up the throttle control, and looks well greased and clean.
    The slide looks in very good condition and only has some very fine slide marks on it. It does not appear to bind or stick anywhere, even after many times of twisting the throttle
    The idea that the slide holds up under vacuum is interesting but the return spring although not strong should take care of that pressure, I would have thought.
    Im wondering if dirt can get sucked down from the inside of the throttle cable at max vacuum and into the carb, ie.trying to get passed the slide but causing it to stick instead. I also thought the return spring was expanding when fully compressed into the slide and causing it to expand inside the slide and jamb it, but these are only ideas I have. everything else appears just fine.
    The bike is a 1998 model, so the carb doesn't appear too worn

  11. #11
    Join Date
    25th March 2004 - 17:22
    Bike
    RZ496/Street 765RS/GasGas/ etc etc
    Location
    Wellington. . ok the hutt
    Posts
    21,234
    Blog Entries
    2
    The vacuum isn't that strong on a 2 stroke esp compared to a large bore 4 stroke. May be enough to hold the worn slide against an edge. But from the sounds yours is mighty fine so scratch that. The top doesn't have much vacuum either. However if water gets in it can cause issues.
    Don't you look at my accountant.
    He's the only one I've got.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •