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Low RPM motor propelling a highway vehicle

  1. Nov 12, 2009 #1
    Good Morning All!

    Is it considered poor engineering to gear up a 100 RPM high torque motor
    to achieve a 1000 RPM medium torque final drive?

    What would be the major drawbacks?


  2. jcsd
  3. Nov 12, 2009 #2
    Could be done no problem.

    Would be a pain to drive as you don't have much rpm to play with and would therefore require lots and lots of gears to get a decent range of speed.

    I's like an ultra extreme version of a truck engine, huge torque low power low rpm. therefore requires tons of gears.
  4. Nov 12, 2009 #3
    No problem. The other way is not preferred though.
    That's why diesel engines are used in passenger cars as well as in trucks while petrol engines aren't used for trucks though by gear reduction you could produce enough torque.. Frictional power loss and engine life are two dominant factors which decide the suitability here, i think.
    This reason is also linked to the one why people advise you not to ride in low gear very often.
  5. Nov 12, 2009 #4
    Hi Folks,

    Sorry, I should have been more precise...

    Assume enough torque is available to allow standing start without downshifting, as with a steam engine or electric motor.


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