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Idle going crazy!

Discussion in 'Bling and Appearance' at netrider.net.au started by e, Feb 8, 2007.

  1. only about a month ago I got my bike's carbies balanced and replaced all spark plugs.

    now, every once in a while the idle fluctuates and the revs go low to a point where the bike stalls. sometime i have to adjust the idle to 2500 to avoid stalling.



    does this mean the jets and needles need to be replaced?
    what causes this to happen? It seems as though there is not enough fuel going into the carb.
     
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  2. sounds like an electrical problem. get ur regulator checked.
     
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  3. As far as I can see its nothing to do with electricals. its definately lacking fuel intake. bike keeps running as long as i keep the revs high enough to prevent stalling. this is on idle, like at the traffic lights.

    otherwise it rides fine.
     
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  4. who tuned your carbs?

    did they just balance them or did they also do / not do the mixtures?

    EDIT: what bike you got?
     
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  5. got a cbr250rr. got a mechanic to do it.
    I thought balancing/tuning them involved adjusting the mixtures also???
    sorry for my ignorance. kinda new to riding.
     
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  6. Hmmm, sort of sounds like a sticking needle and seat, or other fuel delivery problem to me.

    Regards, Andrew.
     
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  7. so carby rebuild... you think?
     
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  8. Don't dismiss the electrical just yet. I chased my own tail recently on a problem that I swore was carbies.

    Turns out the non-R type spark plugs specified in the NGK cataloque are no good for Australian modles. Other models must have a resistor in the cap.

    It worked OK at speed, but would stall accasionally at the lights. when I pulled a plug, one was sooted up and it's mate (two plugs per coil) was fine.

    thought it must be carbies. Turns out the lack of resistor means it fires fine on one cyclinder at the expense of the other.

    I too was getting by, by turning up the idle.

    Check your plugs, your caps and make sure all the connections are good
     
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  9. Man.. that sucks. :(
    mine's not an Australian model.
    would you know what I should be using iBast?
     
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  10. I would start there also. Check the connections to your battery, the earths to the frame, and get the reg/rec checked out.

    If the system isn't supplying enough voltage to the plugs the bike will stall, up the revs and the spark may be strong enough to allow the bike to run.

    If you have a multimeter follow this fault finding chart to eliminate all potential electrical problems:

    http://www.electrosport.com/electrosport_fault_finding.html
     
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  11. whack some carb cleaner through it. worked wonders for my old thing when it played similar tricks. if it is fuel it might save a mechanics bill and if its not its $20 or so.
     
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  12. ok things to try/look at before a waste $500 on a carby rebuild.

    1. Check spark plugs and connections.
    2. try a carby clearer... Which one do you recommend? would a car one work or will it fark up the engine?
    3. Check out the regulator. What does a regulater do adn where can I find it on the bike?

    thanks for all your help so far guys.
     
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  13. Nulon total fuel system cleaner is great.
    I also cannot stress highly enough fitting a fuel filter to teh bike if it does not have one. It almost totally guarantees you'll never have to touch the carbs again. Be sure and use a decent one though, one with ends the same size as your fuel line, tto avoid ccreating a restriction.

    Regards, Andrew.
     
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  14. :WStupid:
    nulon total fuel system cleaner, but adjust the amount to your tank size.
     
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  15. is this nulon stuff specifically for motorcycles or are they for cars. sorry for the stupid question. :?
     
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  17. thanks dude!
    will be going to Super Cheap this afternoon to get me some.
    who knows it might just solve the problem.

    the bike's been good though for the last couple of days. wasn't playing up last night either.
     
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  18. lookin good so far. changed oil and applied nulon total fuel system cleaner (500ml) into a full tank, idling fine at the moment. really hoping this has solved the problem but i'll see if its the same tomorrow.

    Not putting my $500 back into my wallet yet :cool:
     
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  19. http://www.ducatimeccanica.com/dellorto_guide/dellorto_4.html
    good page about tunning carbs
    http://www.ducatimeccanica.com/dellorto/dellorto_manual5.html
    and another good page ,site
    http://www.ducatimeccanica.com/dellorto/dellorto_manual4.html
    step 5 is great for max performance , and as said in step 5 check the needle and seat closes the fuel of when it should, a easy test for that is when carby is of bike turn it upside down ,attach a vacuum gauge to were the fuel line went in carb ,it should hold vacuum if needle and seat is working correctly
     
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  20. thanks for the insight dude. i will check that out.
    too bad i don't have a vacuum gauge. is this something thats easy to get hold of?
     
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