Question about 2001 Yamaha SR 125

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Just taken carb off of a Yamaha sr125

There are two plastic pipes coming off of it, not connected to anything, one was once a clear pipe and cut at an angle, other one is black.
Bike was ever so slightly lumpy and a small loss of power was noticed...checked plug, air filter, etc.,
Are these pipes supposed to be connected to anything?
This bike was bought recently, looked like it had never had an oil change or any basic maintenance. 22k on the clock
This bike is a T reg

Posted by on

  • kitten_art Nov 17, 2008


    Bike still running rough even though we have cleaned carb, changed air filter, checked plug, lead, fuel line. Wont tick over nicely. Throttle cable seems to be sticking, oiled it, but still not returning to tick over when revved. Oiled the carb throttle slide.

    Sounds very tappity, but local bike shop said that was nothing to worry about.



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Offhand, I would suspect the clear tube to be overflow while the black (smaller and connected at the bottom of the bowl near a bleeder screw) would be drain hose for removing stale or contaminated fuel inside the carb's bowl. As long as their is no suction on any of the tubes with the engine running, you should be OK. Should there be suction felt at the free end, then it should be connected somewhere and most likely would be to the fuel valve/petcock or must be plugged.

Just a start, do postback how things turned up or should you need additional information. Good luck and Thank you for using FixYa.

Posted on Nov 17, 2008

  • Louie  Role
    Louie Role Nov 18, 2008

    Hi again,

    Appreciate the postback and the rating.

    To your added concerns:

    • Bike still running rough - rough idling could be due to vacuum leak. This would be evident if adjusting the air jet does not affect the idle. Another that couold be tried is temporarily running the bike without the air filter and see if there is any change;

    • Throttle cable seems to be sticking - have you tried cleaning the accelerator cable out of the bike, using gasoline? Some cables could have frayed ends, rusted housing, crimped housing. Another idea is reroute the cable. One more area to look into would be the throttle itself;

    • Sounds very tappity...nothing to worry about - have to agree.
    Would appreciate update on any developments.


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