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I want some advice on motorizing my bike.

  1. Apr 10, 2012 #1
    Hi!

    I thought of motorizing my 2 wheeler.
    1) Now i want to know how much Voltage (DC motor) is required to turn my wheel.
    2) The source of energy? (Maybe Electric). If electric, I know it will be difficult to use batteries to run the motor. Considering car batteries, they are just too heavy. Any suggestions?
    3) Throttle. I need some help on that as well, as in synchornizing the wheel movement with the throttle.

    Thank You.

    Regards,
    math_way
     
  2. jcsd
  3. Apr 10, 2012 #2

    psparky

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    Gold Member

    I'm assuming you want to go more than 10 feet?

    If so.....4 car batteries hooked in series for 48 volts outta do the trick.

    I'm guessing 1 HP outta do.....that's about 746 watts for a 48 volt dc motor.

    P=IV

    746=I*48

    Current will be 15.54.....so figure 20 amps with magnetic field losses and so forth.....#10 wires outta do the trick to the motor.

    For throttle....use the same thing they use on the tyco trains....that little slide device that controls the speed of the train.

    Have a nice day.
     
  4. Apr 11, 2012 #3
    But each car battery weighs roughly 20 lbs... and 4 such batteries will weigh about 80 lbs. That's a little too much weight... any alternative?
     
  5. Apr 11, 2012 #4
  6. Apr 11, 2012 #5

    psparky

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    Sure.....two 24 volt batteries in series for 48 volts. Your motor scooter will now go half the distance as the 4 batteries.

    Electric powered vehicles are difficult to make....and as you can see the power to weight ratio is not very good. There are some electric cars now....but they aren't exactly lighting the world on fire. Not yet anyway.

    Try a gas motor. The power to weight ratio is amazing.
     
    Last edited: Apr 11, 2012
  7. Apr 11, 2012 #6

    psparky

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    Here's possibly a better idea that would be more fun.

    Power an DC motor with an AC generator into a full wave rectifier. The AC generator would be powered by your legs.

    If you could get 1 HP out of your legs....this would translate into less than 1 HP to your motor due to heat and magnetic field losses....but still would be kinda nifty since you are just looking to play around.

    Maybe you could add a small battery as well that could assist or get charged by your generator as well. Then figure out a way to charge your battery when you were going down hills and so forth.........just like the hybrids.
     
  8. Apr 12, 2012 #7
    Nice Idea! I too thought of converting Mechanical Energy to Electrical Energy, therby powering my motor bike with the electrical energy. Sounds great! I'll see what I can do. And I'll update you on my progress. Thank You!
     
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