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Old 01-11-2011, 09:20 AM   #1
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Questions?? How exactly does it work???

Hello all! Im the kind of person who cant just know somthing but has to understand it. SO, what exactly causes my Sprint 2 drift to stop? When I apply the brakes, what is causing it to brake? Thank you!
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Old 01-11-2011, 10:50 AM   #2
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Hello all! Im the kind of person who cant just know somthing but has to understand it. SO, what exactly causes my Sprint 2 drift to stop? When I apply the brakes, what is causing it to brake? Thank you!
Any electric motor acts just like a generator when a load is applied to it. The amount of load determines the amount of drag.

Think about a generator you might have at home for power outages. It's basically just an electric motor being turned by a gas motor to produce electricity. When you start it up with no devices plugged into it, the gas engine has enough power to keep spinning at idle. As you plug in more devices to it, the load increases and the gas engine has to throttle up to deal with the increased drag.

So, brakes work by basically creating a short across the motor. This causes drag on the motor, slowing the car down. By varying the resistance of that short, you can vary the amount of drag.

You can test this yourself with a simple experiment. Hook two brushed motor together at the shafts, just like an old Buds dyno or CE Turbo dyno. Hook a battery up to one. It will run and spin the unpowered motor quite easily. Hook a volt meter up to the unpowered motor and you will see that it is generating a voltage. Now short out the terminals on the unpowered motor. You will hear the rpm's drop dramatically due to the increased load. If you use resistors of varying values to do the shorting, you will get different changes in load. This is exactly how the old Buds dyno worked.
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Old 01-11-2011, 03:53 PM   #3
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Now that everthing is electronic with speed controls, how it works is not clear. Back in the old days when everyone used a wiper arm and a reostat (big resistor with varying degrees of resistance) it was more obvious because you can see where the power is going by following the wires. Brake was a dead short on the reostat. I had one with reverse which had a micro switch at the brake end which when engaged would reverse polarity and give me full reverse.
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Old 01-11-2011, 08:07 PM   #4
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Thank you gentlemen for the responses I appreciate it!
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Old 01-11-2011, 08:40 PM   #5
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SO, what exactly causes my Sprint 2 drift to stop?
Curbs, parked cars, etc.
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