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Sizing a mototr to the right torque

  1. Jan 4, 2004 #1
    Hello- new to the board and had a question for anyone that can help. I am trying to figure what size motor I will need for a project. My brother has built a custom motor cycle and to showcase it at the carshow we were going to mount the motor cycle on a platform and rotate it at approx. 1 revolution per minute. the bike weighs approx. 650 pounds. I am not sure if we should use a AC or DC motor. I know the length of the shaft and will need to be figured as well. I am open to any suggestions. We thought a DC moto rated @ 1.5 RPM and 18 ft/lbs of torque might work but I thought I would check with someone that knows a bit more on the subject. Thank you. Please feel free to email me any suggestions-Rick
  2. jcsd
  3. Jan 5, 2004 #2


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    Science Advisor

    The torque sounds about right. I calculate that your display with motorcycle on it will spin up to the desired 1rpm in about 1 second. That's provided your friction is small compared with the motor torque.

    I would guess you should use an AC synchronous motor. A DC motor wouldn't operate at the correct rpm without some kind of speed sensor and feedback.
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