any thing here look like it is built to fail?

Discussion in 'Motorized Bicycle General Discussion' started by tvc15, Aug 9, 2010.

  1. tvc15

    tvc15 New Member

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    Hey, I wanted to see if anyone has any comment on my electra engine mount. I milled the support from aluminum this weekend to some pretty tight tolerance so it is secure with stainless bolt down the center. The bracket is aluminium now but I'm thinking that steel is a better option. Please let me know if you guys have some thoughts...THANKS!
     

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    #1 tvc15, Aug 9, 2010
    Last edited: Aug 9, 2010
  2. 2door

    2door Moderator
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    If by "allow" you mean aluminum, by all means don't use it. Steel is the only way to go and it needs to be just a little heavier, thicker than what you have which looks to be about 1/8". I tend to build heavy but I'd probably go with 1/4" minimum. But that's me.
    Tom
     
  3. Mac

    Mac New Member

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    Concur!
    The mount to the frame looks substantial, the .125 Aluminum "standoff" I feel will be inadequate for 3 reasons. 1. with that thin of a standoff you are concentrating the shear points on the engine mount hardware to a very small area of the bolt shank. 2. The material the standoff is made of looks like 1100 series Al.(looking at bend radius) soft, will bend torsionally, causing chain misalignment. 3. The right side engine bolt will be under tremendous load(think of the chain pulling back on the motor real hard), this coupled with vibration = Failure. Suggest using the same material as the frame mount, angle drill and countersink a new standoff so the end result is the entire mount is the thicker material. Just my 2 cents. Still a good job!

    Mac
     
  4. Kevlarr

    Kevlarr New Member

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    Kind of confused, if you have access to a mill why not make the entire mount one piece extending from the motor right down to the frame?

    Do away with the standoff entirely.
     
  5. tvc15

    tvc15 New Member

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    Sherline mini mill, I use it to build scale steam engines, this build is out of it league
     
  6. Kevlarr

    Kevlarr New Member

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