It Ain't the Spark Plug !

Discussion in 'Motorized Bicycle General Discussion' started by Wheel Rush, Sep 28, 2008.

  1. Wheel Rush

    Wheel Rush New Member

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    The engine revs fine, the carb is getting plenty of fuel, it just doesn'r want to run when I let out the clutch !

    It starts jerking and bogging down.

    I checked the filters there OK.

    Any ideas, what I'm looking at ?

    This seems to have started, when I loaded the basket on tthe back with fishing gear for a sprint to the beach, Maybe thirty pounds, I adjusted the clutch about that time, it may have been to tight, I just loosened it a bit, still no change.

    Could this be a clutch going bad, I'm a little mean to it.

    Or could it have some grease on it, I noticed the cover was a little greasy around the edges, however last time I grease those gears, I thought I only dabbed it.
     
    #1 Wheel Rush, Sep 28, 2008
    Last edited: Sep 28, 2008
  2. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    So it idles fine? Revs fine with clutch disengaged?

    Only khraps out when you load it?

    So I assume by your header you have a new plug and plug wire.

    Have you checked for air leaks?
     
  3. Wheel Rush

    Wheel Rush New Member

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    No new plug wire, just a new plug, right, it starts stuttering when I engage the clutch, I have not checked for air leaks, what the sure fire way to check the manifold connection that meets the carburetor, that's the only one to check in this case isn't it ?

    If its leaking then it is sucking air, correct ?
     
  4. stude13

    stude13 New Member

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    yes, squirt some starting fluid or something like it at carb connections, base gasket, head gasket and head bolts.
     
  5. Wheel Rush

    Wheel Rush New Member

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    Ok I'll let you know.
     
  6. Wheel Rush

    Wheel Rush New Member

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    I didn't have any starting fluid but I tried some Carb Cleaner, nata !

    As soon as the work load is applied it bogs down, I just tried it and it seems not to stutter or jerk quite as much but it bogs down readily as if the demand for gas has gone up and it isn't getting it. I can see the gas gurggeling through the line filter, but I put a connection line in its place and there was no difference, so if it's a fuel demand problem its in the carb, I guess ?
     
  7. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    So you have a real fuel filter, right?

    I suspect something might be clogging your jet.

    How many miles on the thing? It was running great before right?
     
  8. Wheel Rush

    Wheel Rush New Member

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    Pablo,
    Exactly, I did find a lump of garbage in the inner tank filter but it was not enough to make any changes, I don't know how many miles I have but I think this is the end of the fourth gallon.

    I have an inline filter the paper kind in the see through plastic container, so how would anything get past that ?

    I'm ready to take the carb off and give it a once over but I would like to have some instructiuon graphics, know where I can get what I need ?

    Thanks for your help.
     
  9. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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  10. Wheel Rush

    Wheel Rush New Member

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    Ok I'll check it out the photos are still downloading, let me ask you, how can I find the timing mark ? I mean I may have to check the igniting time.
     
  11. Wheel Rush

    Wheel Rush New Member

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    Like I said the in line paper filter should make it impossible, so before I rip off the carb, can anyone tell me is there a way to check the ignition timing, on a 2 cycle engine, I mean if it were off as by a degree like a four stroke, with eight cylinders I can understand adjusting, however if a two stroke single cylinder is off, I think that it would have to be something like 180 degrees ? So, there must be something I'm missing, where's it at ??
     
    #11 Wheel Rush, Sep 28, 2008
    Last edited: Sep 28, 2008
  12. misteright1_99

    misteright1_99 New Member

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    There is no ignition timing, it is set in place by a key on the shaft, now if the key is partially sheared that would change the timing. I read a post that someone had an armature where the air gap was too wide, and he closed it with channelock pliers. When I was jetting my carb I came across a similar problem got it running fine in the garage but when I rode it it bogged real bad, turned out to be too small a jet, you might try moving the needle clip down one slot and richening the air/fuel mix, or check that the jet is not plugged...
     
    #12 misteright1_99, Sep 28, 2008
    Last edited: Sep 28, 2008
  13. Wheel Rush

    Wheel Rush New Member

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    misteright1_99,

    " you might try moving the needle clip down one slot and richening the air/fuel mix, or check that the jet is not plugged..."


    Do you mean, . . .

    " you might try moving the needle clip down one slot and," thereby richening, "the air/fuel mix," . . .

    or is there an adjustment to do that ? I have not had these off or apart since I put this machine together in June.
     
  14. misteright1_99

    misteright1_99 New Member

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    Yes that is what I meant. That is the only way to adjust the mixture on the stock carby...

    Post # 5 http://motorbicycling.com/f30/motorized-bicycle-carburetor-install-rebuild-302.html
     
    #14 misteright1_99, Sep 28, 2008
    Last edited: Sep 28, 2008
  15. Wheel Rush

    Wheel Rush New Member

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    OK, I have it apart and I'll look at that assembly to see if I can make the adjustment down, but I did not find any dirt in there where the needle is, unless it was microscopic.

    Can you tell me, why all of a sudden this would need adjustment ?

    Just what does the adjustment do ? I assume it allows a wider gap for the needle, and thereby letting the gas flow be greater than before.
     
  16. misteright1_99

    misteright1_99 New Member

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    Yes that is true moving the taper of the needle up sooner. While apart I would also unscrew the jet and spray it with som carb cleaner also. That is the smallest orfice in the carb...

    If it is a piece of carp in the jet it would be all of a sudden...
     
  17. Wheel Rush

    Wheel Rush New Member

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    OK, it all looks pretty clean, I'm going to Kings to check out that needle slider assembly before taking it a part to move the adjustment. I put it in there a few months ago, but I'm going to need the schematic. I'll let you know how it works out. Thanks much.
     
  18. misteright1_99

    misteright1_99 New Member

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  19. Wheel Rush

    Wheel Rush New Member

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    Hey Misteright1,

    Got it back together and pretty darn sure the intake is sucking air. . .so I am gonna need to check out the solution, which I will more than likely find in the archives, I did see where Norman used silicone something or other, in a previous thread. I see you posted the schematics in last post and have made note of it, and will check it out, much appreciated, thanks!
     
  20. Large Filipino

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    Only because it hasn't been mentioned here yet but when this happened to me my exhaust was restricted because I go a bit heavy on the oil mix. After opening it up and scraping all the gunk she ran like a banshee.
     

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