80cc Mystery

Discussion in 'Motorized Bicycle General Discussion' started by MrLarkins, Jun 17, 2008.

  1. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    I doubt it's a misbalance - I think your needle taper could be ODD. Tell me this, in the video - when you get to the nasty early midrange flutter - if you hold it there, does the engine die?
     
  2. MrLarkins

    MrLarkins HS Math Teacher

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    hmm, i'll check
     
  3. Wheel Rush

    Wheel Rush New Member

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    Mr. Right,

    I am not a mathamatician nor a mechanic to speak of, but I

    am thinking 128 oz Divided by 20 = 6.4

    so 1/20th would be 6.4 ?

    Right ?
     
    #43 Wheel Rush, Jun 23, 2008
    Last edited: Jun 23, 2008
  4. MrLarkins

    MrLarkins HS Math Teacher

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    no, the vibration is so bad though that gas comes out of the carb through the primer!
     
  5. misteright1_99

    misteright1_99 New Member

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    I am not a mathmatician either so I use a calculator lol. I believe though, I entered the figures correctly. He has 8oz of oil and wants it mixed 20:1. So
    8 x 20 = 160 or 1 gallon and 1 quart 128 + 32 = 160. Correct? Sorry if I calculated wrong.....
     
  6. Wheel Rush

    Wheel Rush New Member

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    OK, but double check, I have a gallon of gas I need X amount of oil for a 20:1 ration, so 128/20=6.4 oz.

    Right Sir ?
     
  7. misteright1_99

    misteright1_99 New Member

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    You are correct but his question was "I have 8oz of oil, How much gas for 20:1"
     
  8. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Argghh...but hard to determine if this is a cause or effect.....
     
  9. MrLarkins

    MrLarkins HS Math Teacher

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    rgr that...bikes tore apart for two days whilest the rear wheel is in the shop for axel/freewheel repair and bearing overhaul!
     
  10. Norman

    Norman LORD VADER Moderator
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    you must have a flywheel let loose if its shaking the fuel out of the carb at least that is what I'd look for but to do that you need to take it apart and possibably split the crankcase.
     
  11. MrLarkins

    MrLarkins HS Math Teacher

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    :(
    i am not looking forward to that!
     
  12. jasonh

    jasonh New Member

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    I just thought I'd chime in here. I don't have one of these (yet) so feel free to give me the smackdown with a large trout if I'm wrong...

    Don't these motors have a choke system? Honestly the video sounds like what I get if I start up a leaf blower or weedeater without properly using the choke...

    Just a thought.
     
  13. Egor

    Egor New Member

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    That is an ignition problem, not with the fuel. If you are willing to do a simple check. Take the plug cap off put the wire on the plug and start the engine now have someone else turn the throttle and as they do pull the plug wire just enough away from the top of the plug to watch the spark. As you run the engine you will see it cut off and on. The reason I told you to get help to do this is you need to keep your hands off the bike so that if you pull it too far away it will not bite you. If you have an intermittent spark I would blame the coil first. There is a chance you can use some cold shot and spray the coil with it and chill it down, it will start to run when cold, sometimes. That is an indicator. I have had many motorcycles with that problem. Rich and lean refer to the amount of fuel you are delivering, you can't change the amount air. Your piston is washed, so it is rich from not com-busting, the result of bad spark. Have fun, Dave

    PS: If you don't have the courage to hold the wire away take a piece of clear fuel line and put it over the end of the wire, next slip the tube over the end of the plug, get the wire close to the plug and start the engine, you can look through the tubing and watch the spark.
    I will add another PS: Take the kill wire off before you do anything, they are junk.
     
    #53 Egor, Jun 24, 2008
    Last edited: Jun 25, 2008
  14. Kulana Kruiser

    Kulana Kruiser New Member

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    This was like reading a really good mystery, just like you had stated in your thread name. But it's still missing the climatic ending! -
    Did you ever discover the reason for the power loss?

    One thought not mentioned so far: is the carb perfectly vertical? - if not the float could be unbalanced, and closing off the fuel prematurely, thus starving the motor. You may have a full fuel bowl when starting off, and then it may provide only intermittent fuel as you ride due to vibration.
    It's something simple, but vital to have this right.

    I have a Powerking as well, so I have a vested interest in what you discovered.

    Kruisin style,

    Troy Fitz.

    Since this is my first post on this site, figured I should toss up a pic to validate my credibility:D

    [​IMG][/IMG]

    [​IMG][/IMG]
     
  15. Dave31

    Dave31 Moderator
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    Welcome Troy to the forum, glad you joined us :D

    :eek: That is one sweet looking ride (^) What kinda seat is that? how's it feel?
    :ride2:
     
  16. nogoodnic

    nogoodnic New Member

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    Hey Kulana, have you re-enforced your fenders yet? Wally World bikes are known for the fenders falling off while riding and causing some really bad accidents. There is a thread somwhere on how to re-enforce them, I'll try to find it for you...Kelly
     
  17. nogoodnic

    nogoodnic New Member

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  18. jf30cp

    jf30cp New Member

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    I feel the same way about it....looks like you ran it to lean. what is the elevation where you live? I live in Bend oregon about 3500 feet. i run my new whip with amsoil saber at 20 to 1 . also the carb needle is on the 2nd clip from the top and seems to be running a bit rich.. but anyway, when you get your new parts i would at least run the 20 to 1 with a good 2-stroke oil like Amsoil. also dont rev it up to much for the first 3 or 4 tank fulls. like half throttle. this has worked for me. I am no expert. if you have anymore questions i myself would ask NORM or PABLO....they seem to know what the **** is going on here. so good luck. jeff(c)
     
  19. Kulana Kruiser

    Kulana Kruiser New Member

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    Not thread stealing, just replying:

    you mean like this?(^)

    fairracing31::::
    It's a Schwinn comfort seat - $20.00 - very comfy when Kruising.:ride2:

    My elevation is 4,600 feet, I have a Powerking 80 - or whatever, and have my fuel setting on the first clip closest to the end of the end of the cable.
    I haven't had any problems at all and have 160 miles on mine now.
    I use a 20:1 ratio - which I use a paint mix ratio cup, and shows exactly 6.4 onces for 1 gallon of gas.
    I use Amsoil - Interceptor, and it has worked great. Almost no blow-by through the exhaust at all.
    I decided to check my plug today, and here is the result: - looks perfect to me. - ok, I guess not, I have been limited to only 4 pic's.
    I still think your problem is elsewhere. Again check the carb to see if it's perfectly vertical.

    Krusing Syle,

    Troy Fitz.


    [​IMG][/IMG]

    [​IMG][/IMG]
     
  20. Wheel Rush

    Wheel Rush New Member

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    Hey Kaluna,

    Don't mind me, but I was just thinking it would be a great idea if you could, I guess they call it, "tagging", photos or like captioning them and describing what the reader is looking at. I am only, conjecturing this, I am not suggesting it, but it's possible you may not have thought of it, I do that kind of thing all the time.

    Anyway, there really good pictures, . . .

    BTW, if you don't mind, what exactly is that in the first picture just above ?

    I thought I was going to get a look at a near perfect sparkplug.

    OK, I know now what I'm looking at !

    Did you paint the engine head black ?
     
    #60 Wheel Rush, Jul 9, 2008
    Last edited: Jul 9, 2008

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