# Electric go kart

I know this may be a physics question but, will a 48 V 1000 W motor with 3000 rpm be able to move a 500 lb go kart on a concrete sidewalk? And, can I use one 12 V 101 Ah 27 A deep cycle marine battery with a step up converter (For the 48 V) to power the motor? If so, what step up converter would I need? A 12 V to 48 V 27 A step up converter or can I use a regular 12 V to 48 V 1A converter?

• is the sidewalk going down a steep hill?
– jsotola
Jul 17, 2020 at 3:41
• " or can I use a regular 12v to 48v 1A converter?" - 48V @ 1A = 48W. Your motor is rated at 1000 Watts. What do you think? electricscooterparts.com/motor-power-calculator.html Jul 17, 2020 at 5:02

This cannot be answered as is because almost all the critical information is missing.

Mechanical Power required to move to the go kart is determined by the force and speed required

Motor Power can converted from mechanical power and be put in terms of motor torque and motor RPM.

Battery power can be converted from motor power and put in terms of voltage and current.

Force required (specifically the force at the edge of wheel) is determined by the rolling friction (wheel hardness and terrain roughness and hardness), incline, mass, wheel radius, and acceleration.

Acceleration is determined by speed and the time you want to reach it in.

Speed are related to each other wheel RPM and wheel radius. You choose the speed and wheel radius you want and we can tell you the wheel RPM required.

Motor torque is calculated using force, wheel radius, and the gear ratio

Motor RPM is calculated by using the wheel RPM and gearbox ratio

We can estimate the rolling friction if you tell us the type of wheel and terrain. But we can't guess things like acceleration, incline, wheel radius, top speed. You have to tell us those. Technically you don't need to tell us the gearbox ratio. If you give us everything else and the motor you have we can tell you whether it's possible and we can tell you the gearbox ratio you will need if it is possible.

In short, if you tell us your mass, wheel type, terrain, acceleration, wheel radius, and top speed we can tell you the mechanical power, wheel torque, and wheel RPM required.

From there, if you give us the motor, we can tell you if it will work and what gearbox will be needed to make it work. If, instead you give us the gerabox, we can tell you what motor will be needed to make it work.

Once we have the motor, we can tell you what battery will be needed.

You could figure this out of yourself if you learn the following relationships:

• force, mass, and acceleration
• acceleration, velocity, and time
• power, torque, and RPM
• power, current, and voltage
• torque, force, and wheel radius
• and understand how torque limits acceleration in a wheel while max RPM limits top speed and how the two work together (basically why you change gears in a car)

Then all of that comes together and you can figure things out by using this: How can I calculate the power and torque required for the motor on a wheeled robot/vehicle?

All that is to say you need to cover some basics, particularly the most basic power calculations before even attempting to think about a project like this. Someone can't really be expected be able to figure out how to calculate the power and force required to move a vehicle on their own after some Googling, but to not recognize that 12V@27A and 48V@1A are nowhere near 1000W means you haven't done enough basic research.

Oh, and do not run use a DC-DC converter for your motor. That's a bad idea. Converting voltage for a high power device means a high power DC-DC converter which means, big, heavy, and expensive plus you get all the associated inefficiency, fragility, and complexity. Even nastier than it sounds because motors can have current surges so your DC-DC converter will have to be even bigger. Much better to cut out the middleman and just get the actual battery voltage you need straight out of the battery.

While DKNguyen's answer is accurate. I believe you're looking for a more holistic answer.

1. Will it move? Absolutely it will move if you give it enough gear reduction. You could move the cart with a minuscule motor and a worm drive if you don't mind it creeping along. So the question is, how fast will it go? Or more accurately, how hard can it accelerate? and what will the top speed be?

2. Ok how fast? Well, without getting into a bunch of math; the best way to determine this is to compare the motor to what other go carts have (in terms of wattage). 1000W is 1.3 horsepower. A 50cc 4stroke motor by comparison has about 2.7hp. So this thing is going to be a bit anemic, slower even than a golf cart. Keep in mind that the gear ratio will have to be correct to even get this level of performance.

3. Can you drive it using a step-up converter? Well.. because 1000W is quite low for a 4 wheeled vehicle ..maybe. I'm seeing some chinesium converters amazon that meet these specs. But afik this is not a common thing. A 48V 1A converter can only supply 48W, so no you can't use that. I would try to find 4 smaller batteries instead and wire them in series.

https://www.amazon.com/Hyuduo-Converter-Voltage-Regulator-Stabilizer/dp/B07NM52VV5 that is over a horsepower.

One HP is 550 foot_pounds.

Thus one-foot radius wheels will have 550 pounds of push.

And 6" radius wheels will have 1,100 pounds of push.

So, yes, the go-kart will move.

• Why are you treating horsepower as torque? Jul 17, 2020 at 5:14
• This is not accurate. You cannot convert horsepower into torque.
– Drew
Jul 17, 2020 at 8:55
• 1HP is NOT 550 foot pounds. Jul 17, 2020 at 9:51