Noob with a problem

Discussion in 'Motorized Bicycle General Discussion' started by joabthebugman, Jul 16, 2010.

  1. joabthebugman

    joabthebugman New Member

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    I bought a used Gary Fisher mountain bike with a Skyhawk motor and a broken chain for $100

    The motor supposedly ran and I figured for the price I at least had a good bike and a bucket full or kit parts

    The problem I'm am having is that the motor seems to have compression only half the time

    When I first tried to start it I would pedal and sometimes I would get good compression and it sounded like it would start, and sometimes it had nothing

    I put it on a stand and pedaled by hand with the clutch engaged
    Half a sprocket worth of turning had compression and half did not

    Any ideas, or am I looking at the wrong thing
     
  2. corgi1

    corgi1 New Member

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    Might look in the clutch side(water drop shape)and see if the little gear is cracked or there is some metal powder(shavings) around the small gear,,,If the motor is on the bike and the clutch handle works ,you mightlock the handle and adjust the flower nut(clutch adj.)while the cover is off
     
  3. Creative Engineering

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    You sir...have a long road ahead of you! From reading your post, it is impossible to diagnose what is going on!

    Once a bike is run-in a bit, I can stand beside it, lift the rear wheel, and kick start it with the pedals...by hand, not a chance!

    Jim
     
  4. joabthebugman

    joabthebugman New Member

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    No no
    Wasn't trying to kick it over by hand
    just checking the compression issue

    I noticed the on again off again compression issue while I was trying to pedal it off
     
  5. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Sounds like the clutch was slipping?

    You can't have part time compression.
     
  6. Mind_Reader7

    Mind_Reader7 New Member

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    Actually, you can. I haven't expereinced it on these motors, but when a motor becomes really crap, once they're warm there's basically no compression, but for a cold start they're fine.
     
  7. joabthebugman

    joabthebugman New Member

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    Haven't had time to work on anything yet, but I will check the clutch tomorrow

    If that doesn't do it I'll just buy another motor kit

    I'm gonna need some of the parts for my grand daughter's bike anyway
     
  8. Dougan

    Dougan New Member

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    Has to be the clutch.

    Easy to find out too. Just take teh cover off of the clutch and do what you were doing. See if both gears are always moving.
     

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