Bearing Came Apart

Discussion in 'Motorized Bicycle General Discussion' started by Retmachinist, Apr 21, 2010.

  1. Retmachinist

    Retmachinist New Member

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    After haveing built fifteen bikes with the Chinese in frame two stroke, and no major engine problems I finally had one come apart. I figured it was due to over winding a new motor, since I was beating it pretty hard with only about 18 miles on it. I was breaking it in with 32:1 non synthetic oil.
    After tearing it down I see the cage on one of the crankshaft bearings came apart. I also noticed the fit in the case of the other bearing is way to tight. When you turn the bearing you can feel every ball in it. I was wondering if other people who have torn these down have noticed the bearings being fit to tight in the case. I suppose they are all different. Just a crap shoot if you happen to get one where the bearings fit perfect.
    I guess I can't complain since it is the first one I have had a major problem with. At this price they are disposable.

    John
     
  2. flybytaco

    flybytaco Metal Molding Madman

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    ive seen the non caged crowded lower come apart hardcore before never a caged.. 1 in 15 is great john lol
     
  3. Retmachinist

    Retmachinist New Member

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    I forgot to attach the photo of the Crankshaft bearing, missing the cage. Here it is. Motor only had 18 miles on it.

    John
     

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  4. Goat Herder

    Goat Herder Gutter Rider

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    Wow some of these need a little time before they start getting better power. So I keep hearing. I will keep going easy on my break in with the china fo sure now!
     

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