Bicycle Motor Refuses to start

Discussion in 'Motorized Bicycle General Discussion' started by Mopedamauter79, Apr 7, 2008.

  1. Mopedamauter79

    Mopedamauter79 New Member

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    Re: Motor Refuses to start

    I got a hold of my friend and he told me the following:


    - Motor is not flooding

    - Not getting any gas at all.

    - The spark plug was not even wet.

    - It has good compression

    - It has good spark

    - The carb was rebuilt

    - The gas is mixed properly

    - Is possible that the carb ports are blocked somewhere
     
    #21 Mopedamauter79, Apr 11, 2008
    Last edited: Apr 11, 2008
  2. deacon

    deacon minor bike philosopher

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    Re: Motor Refuses to start

    If you are having to deal with the choke in that manner, you have air leaks. Which would screw up your air/fuel mix. If your air fuel mix is not right it won't run either. Most of the air leaks not all but most are from the manifold tube not being sealed.

    Have your mechanic friend check for air leaks. I'm sure he knows how.
     
    #22 deacon, Apr 12, 2008
    Last edited: Apr 12, 2008
  3. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Re: Motor Refuses to start

    Sounds to me like you have a fuel flow problem, maybe an air leak too.

    Just start at the fuel line and check for flow, then go to the carb and take off the float bowl and turn on the gas and see if there is flow there. If, after you confirm fuel flow to that point, check the jet (where the needle goes into it) you may have chunk of crud in there.

    Keep us posted.
     
  4. Mopedamauter79

    Mopedamauter79 New Member

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    Re: Motor Refuses to start

    Here is a quick shot I have of the carb from last year. The carb is fine it's clean. The lever is beside the fuel line. I don't how u don't know what im talking about. The kits all have the same type of carb.

    [​IMG]
     
  5. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Re: Motor Refuses to start

    Well - the carb may not need to come part - but if the bowl is full (is it?) - then either your jet is too small (or has belly button lint in it) or the needle is too large (happened to me)......

    Oh and your clutch spring doesn't go there.
     
  6. Norman

    Norman LORD VADER Moderator
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    Re: Motor Refuses to start

    take off the fuel line to the carb, turn on the fuel, you should have a good flow if not your tanks fuel valeve is clogged with tank crap.clean the fuel tank valve and srceen if it has one.
    take the carb apart under the float arm is the needle either tke it out and blow air through it or hook up a chunk of fuel line and blow throught the inlet of the carbs fuel line to make sure the flost needle is not plugged.
    take off the float chamber and blow through the main jet make sure it is open. the main jet should measure 0.025. your needle should measure around .0700 up at the top close to the clip slots and taper to about 0.065 at the end of the needle.
    there is a vent on the carb take off the aircleaner and look close you will see a smalll 1/8" hole that is drilled and makes a 90 degree turn to the float chamber it needs to be open clean with compressed air ot carb cleaner.
    I've been over all this before with others last resort send me the carb I'll either make it run or we can put it in low earth orbit. its up to you.
    with it all together take the sparkplug off and put a teaspoon of fuel in the cylinder put the plug back on and pedal it.

    Check out my post on the classics on carb tear down and reassemby if you still can't get it going pm me and I will get you going no need to post on this anymore. ok!
     
    #26 Norman, Apr 12, 2008
    Last edited: Apr 12, 2008
  7. paul

    paul Active Member

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    Re: Motor Refuses to start

    i always have to use the lever (choke) on my bike to get it started. full choke or just a little less or the bicycle engine does not even think about starting
     
  8. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Re: Motor Refuses to start

    I was gonna send him my left over NORMAN (DARTH) MOUL carb - but I noticed he lives in one of those foreign countries!
     
  9. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Re: Motor Refuses to start

    Oh and your clutch spring doesn't go there.[/QUOTE]



    Yes it does... there are two clutch springs, this one does go here to keep tension on the clutch lever & cable end.
    He's actually missing the bigger one that is a heat shield so the engine doesn't melt the cable housing. ;)
     
    #29 Venice Motor Bikes, Apr 12, 2008
    Last edited: Apr 12, 2008
  10. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Re: Motor Refuses to start

    Venice - OK yes per the instructions, you are correct. Lots of us don't use that smaller spring. No need. The spring there looks like the larger heat shield one, but I could be wrong.
     
  11. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Re: Motor Refuses to start

    You're right, you can leave it off. (which will also make it easier to pull the clutch lever!)
    I've had many problems with the adjusting screws on the hand levers striping out, & just a little slack in the cable can cause the cable to fall off the engine lever...
    I might actually try removing this spring for a few days to see if I like it better? (it does seem like a better way to go) :oops:

    But yeah.. he needs to put that heat shield on!( you can see how his cable is melting)
     
    #31 Venice Motor Bikes, Apr 12, 2008
    Last edited: Apr 12, 2008
  12. Norman

    Norman LORD VADER Moderator
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    Re: Motor Refuses to start

    it won't melt if he can't get it to run.
     
  13. Mopedamauter79

    Mopedamauter79 New Member

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    Re: Motor Refuses to start

    The carb gets the gas but it's not sending it to the engine or the engine isn't grabbing it from the card. My friend has actually blown through the carb to make sure there would be fuel flow. I will take the air filter off and take a look at what you said. What do you mean exactly by putting a small amount of fuel in the cylinder ? The hole in which the Spark Plug goes into ?
     
  14. deacon

    deacon minor bike philosopher

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    Re: Motor Refuses to start

    My problem is with the top of the carb. Isn't that knarly nut supposed to be down on the carb top.
    [​IMG]
     
    #34 deacon, Apr 12, 2008
    Last edited: Apr 12, 2008
  15. paul

    paul Active Member

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    Re: Motor Refuses to start

    all that is is for taking slack out of the bicycle motor throttle cable.
     
  16. Mopedamauter79

    Mopedamauter79 New Member

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    Re: Motor Refuses to start

    It's also a pic from last year. It was on a different frame last year.
     
  17. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Re: Motor Refuses to start

    If it WAS running good, with this carb... check to see if the jet or inlet needle are clogged!
    Take the float bowl off.. the jet is the long brass tube screwed into the carb housing. make sure there's no dirt clogging up that tiny hole!
    Blast everything with carb cleaner!
    Also put on a in-line fuel filter.
     
    #37 Venice Motor Bikes, Apr 12, 2008
    Last edited: Apr 12, 2008
  18. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Re: Motor Refuses to start

    Yes, the bigger, round one should be down on the barb, it's to lock the cable housing adjustment nut.
     
  19. Mopedamauter79

    Mopedamauter79 New Member

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    Re: Motor Refuses to start

    The needle is brand new. I didn't even have to proper one before. I do now. The entire carb is clean.
     
  20. Norman

    Norman LORD VADER Moderator
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    Re: Motor Refuses to start

    Yes pull the sparkplug out of its hole take about a teaspoon of gas pour it into the sparkplug hole put the sparkplug back in tighten it up put on the plug wire. Turn on your fuel. Breath in and out get on the bike put your feet on the pedals pedal it and then get out the clutch. If it won't fire then you have a problem get your buddy to look at it.
     
    #40 Norman, Apr 13, 2008
    Last edited: Apr 13, 2008

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