NOOB needs crank help

Discussion in 'Motorized Bicycle General Discussion' started by BossKoops, May 25, 2012.

  1. BossKoops

    BossKoops New Member

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    i have a macargi cruiser motorbike with an extra wide pedal crank to fit around my 49cc flying horse engine///
    ok so, i was riding down the street like norm when all of a sudden my crank came loose. The chain came off and i couldnt even brake seeing as i have coast brakes
    ANYWHO
    i dont know how to or even start to fix it. it looks like i just have to take it off and tighten these bearings things that are next to the chain sprocket.
    also it looks like theres metal shaving all inside there. is that terrible?
    .
    HELP
    &
    Thanks
    .
    [​IMG]

    >

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  2. Ibedayank

    Ibedayank New Member

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  3. BossKoops

    BossKoops New Member

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    alright.....
    that didnt explain anything....
    *NEXT*
     
  4. BossKoops

    BossKoops New Member

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    actually that did help a bit
    im a jackass
    but more advice would be helpful
     
  5. killercanuck

    killercanuck New Member

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    On each side of the crank you should have a bearing cup, and on one or both side(s) a locking ring.
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    The outer locking ring(or nut) is what locks the bearing cup in place. Once the cups are set, I lock mine with a screwdriver and some good whacks with a hammer. Remembering that the left side is a left hand thread(!)

    Snug up the cup first, then lock it down good, being careful the cup doesn't tighten too much to bind up the bearings while hammering.

    That's all there is to it.

    gl.
     
  6. biknut

    biknut Active Member

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    Did you actually need a wider crank? I built a Micargi Rover, and the crank arms cleared the motor with no problems.

    You can probably just screw yours back together. I think you'll need a special tool for tightening the lock ring.

    Is the crank you're using a 3 piece, with square tapers on the crank arms? If so you might be able to buy a sealed bottom bracket for about $10 and never have to worry about maintenance.

    [​IMG]
     
  7. donphantasmo

    donphantasmo Member

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    That happened to me once before.. The next morning, I was at my local bike shop, looking at front brakes!!
    Let me just tell you, you need to make sure you have front brakes. Go to a local bike shop, Wally world, or get it from a million places online.
    I also have a cruiser. Relying on coaster brakes alone can get you hurt, or even killed. Invest 20$$$ on front brakes and save your life...
     

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