New stage 2 stuck at crankshaft

Discussion in 'Motorized Bicycle Trouble Shooting' started by Nanfoe, Nov 18, 2016.

  1. Nanfoe

    Nanfoe Member

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    I know we got stuff down there in the crankshaft but am trying to get Ebay to get a refund for me so I don't want to completely disassemble her just yet but for now here are some pics of 17 hours from new. Anyone can tell what it could be? Something came loose from the bottom I think and made its way to the top. This is one for those who know.
     

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  2. crassius

    crassius Active Member

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    well, it is not any of the needle bearings as they always make tiny circular holes

    whatever it was looks to have been soft as it seems to have broken up or smashed flatter when it hit

    there might be more info in a pic of the ports & piston skirt to show where it entered

    could be flashing from a port left after machining, or could be something that fell in before spark plug was in place (had a customer drop a lock washer from gas tank mount and it went right in the plug hole - locked up in 2 seconds and destroyed cylinder & piston both)
     
  3. Nanfoe

    Nanfoe Member

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    Thanks for the reply I've been here all night toying with her, put another cg on the frame with the big head. I know the piston is shot but the head is still good right? Jug look OK. Here some pics.

    Edit : The base of the rod is stuck. The shaft moves though.
     

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    #3 Nanfoe, Nov 19, 2016
    Last edited: Nov 19, 2016
  4. crassius

    crassius Active Member

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    will need to get to shop 'puter to see those pics well - old POS 'puter here just don't cut it : (
     
  5. crassius

    crassius Active Member

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    cylinder looks OK, but there may be some flakes of stuff in ports & maybe a nick in the intake that can all be cleaned up with a small file

    head needs to be smooth enough inside so that there are no sharp points sticking up to collect carbon and become hot spots
     

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