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How can I make my electric scooter go faster

  1. Oct 2, 2005 #1
    I have a 400W electric scooter and it's just too slow. It uses a 400W, 20Ah motor. So I have a few questions:

    What is the easiest way to make this thing go faster without changing the controller?

    Will I burn the motor out with a 36V battery pack (the pack is 3 twelve volt, twelve amp cells hooled up on paralell--does that make is a 36amp cell?)

    Will the increased voltage increase the RPMs of the motor?

    I am trying to do this on the cheap, which means changing as little as possible. I have two of these 36V batteries and a charger, so ideally I would like to be able to solve my problem just by using them. Will it work? Or will I thrash the motor to pieces overnight?
  2. jcsd
  3. Oct 2, 2005 #2


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    Science Advisor

    Bad idea, you're likely to burn out the controller if you apply too high a voltage.

    And if your batteries are in parallel then you have increased the current capacity - in other words longevity - not voltage. In series you gain voltage but the capacity remains the same as the weakest cell in the series.

    To find a cheap solution, the first thing to establish is if the motor controller allows for a full duty cycle (assuming its a PWM) and/or if it automatically speed limits based on back-EMF. If this were the case, then a simple high-current relay bypassing the controller would allow you to increase the speed for cheap with the existing battery system. The relay by itslef would last a decent while before the inductive kick-back would pit the contacts too much, and you could add a flyback diode to prevent that too.

    Otherwise, to go faster you'd need more voltage AND current - in essence more power. And likely a larger controller to handle that, and better cooling for the motor that may need brushes replaced more often and so on.
  4. Oct 2, 2005 #3


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    Gold Member

    You could also, of course, swap the whole drive system from a more powerful bike—motor, batteries, the works. The advantage to that is that everything will already be compatible.
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