Starfire 69cc - Will turnover but seems reluctant to do so...

Discussion in 'Motorized Bicycle Trouble Shooting' started by buzzingbicycles, Mar 1, 2012.

  1. buzzingbicycles

    buzzingbicycles New Member

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    Hi guys,

    Hello from Ireland!!

    Ok so I have a few MBs and one of my Starfire 69cc will not start.
    I've problems before but never this one-

    When I pedal to start and then release the clutch lever the engine will turnover. But it seems strained when it is turning over and it's impossible to pedal for more than 10 seconds because it's so difficult to turnover the engine..

    Sometimes she will get close to starting but something in the engine is making it difficult for the piston or something to run smoothly.. I think..

    Any ideas/people who've had similar problems?

    Is there any way the piston could be misaligned?
    And if so, what is the best way to out the 'head' on and line up the piston..



    I've built around 20 MBs so I'm not a complete newbie..

    Colm
     
  2. rustycase

    rustycase Gutter Rider

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    Gosh, Colm, if you got experience, perhaps you should pull the cylinder and have a look at things just to be safe?

    Good luck
    rc
     
  3. FileStyle

    FileStyle New Member

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    have you tried adjusting the clutch? or maybe a little much compression! try adding another head gasket. just my two cents worth! ( not my first rodeo, but always willing to learn something new)
     
  4. Al.Fisherman

    Al.Fisherman New Member

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    Before I pull the cylinder, I'd remove the chain, (this will let you know if its in the engine or bike) and peddle the bike. If it's not in the bike, remove the spark plug, and magneto cover, and take a 14mm socket and turn the magnet nut clockwise. This will also tell you if the compression is too high.
     
  5. nightcruiser

    nightcruiser New Member

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    Pull the spark plug and turn it over, that will release all compression and it should turn over very easily. If it does turn over easily with the plug out maybe you got liquid fuel in the cylinder, turn it over a bit to clear it out (make sure there is no spark or flame to ignite fuel that may come out of the spark plug hole). Then put the plug back in and see if she runs... If so, you either have a stuck float, a hole in the float allowing fuel inside, or maybe some junk in your needle valve. Make sure you turn your fuel valve off when not riding.....
    If you pull the plug and she is still hard to turn over then you have an issue with the rear wheel, or chain jam, or a clutch issue or something jacked up inside the motor. I would work my way from the rear wheel to the drive sprocket making sure things are ok, then look inside the gear cover, and magneto cover, if you still dont find an explanation I would pull the head and take a look (I would pull just the head at first, not the whole jug). From there you can pull the jug and see if the bottom end seems frozen up. Inspect all your bearings as you go. Hopefully you will have it fixed long before you get to the bottom end....
    Good luck
     
    #5 nightcruiser, Mar 1, 2012
    Last edited: Mar 1, 2012

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