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Circus clown car convert to electric

I want to convert my gas gokart to electric.  Fully loaded with me and the dogs, it weighs less than 500 lbs and does not need to go faster than 15 mph.  We drive on level ground and only need to go around 3 miles per day at mostly walking speeds.

The rear axel has a 9" sprocket with what appears to be #40 chain and I would like to keep that sprocket and chain if possible.  I see that the motors like the the MY1020 have 8mm sprockets.  Is it possible to change the motor's sprocket to fit #40 chain, or should I replace the axel sprocket to accept the 8mm chain?

How many volts and how many watts do I need?   Is that 48 volt 1000 watt motor a logical choice?




A 36 Volt and 48 Volt 1000 Watt motor both have the exact same amount of power so it would require less batteries to use a 36 Volt motor which might keep the cost of parts down without sacrificing power.

MY1020 motors such as our 36 and 48 Volt 1000 Watt models have sprockets for 8mm T8F chain installed on them and sprockets for #40/41/420 chain are not available for MY1020 motors. So if a MY1020 motor was installed in the car then an 8mm T8F sprocket would need to be installed on the axle.

I ran some gear ratio calculation for your modification project using a 36V 600W gear motor and a 36 (or 48) Volt 1000 Watt MY1020 motor and here are the results.


An 8-3/4" sprocket for #40 chain has 54 teeth so that is what I used for the first calculation. The tires look like they are 16" diameter from the photos however if they are a different size then please let me know so I can recalculate.

If a MY1020 motor was used then a 95 tooth axle sprocket for 8mm chain would be needed. This is not a standard size sprocket so it would need to be custom made and we make custom sprocket which can be ordered on this page:

If you can live with a 4.25 MPH top speed then using the 36 Volt 600 Watt gear motor would be the best way to go because the existing axle sprocket and chain could be reused. The car would also have a lot of torque with this setup for going up ramps and inclines, such as when loading onto a truck or trailer, or going up steep driveways. We also have a 36 Volt 650 Watt gear motor with a 550 RPM output shaft speed which would provide a 4.89 MPH top speed with the existing 54 tooth axle sprocket.

For a 3 mile drive on flat ground at 3 to 5 MPH a battery pack made from three 12 Volt 22Ah batteries would do the job.

We can make a kit out of the parts that are needed which is prewired with matching connectors, or the parts could be purchased separately. Please let us know which direction you are leaning towards with the motors and if you have any questions.

Thanks for the quick reply.  Yes, the tires are 16" diameter.  The 36 volt 600 Watt motor sounds OK to me.  Torque to get up ramps is good, but we won't have the speed to get away from rowdy kids, so we'll have to go old school and bite them.  Let's talk about a kit.  Do you have a speed control that can be hooked up like a gas pedal?


Okay that sounds great. Yes we have gas pedal style foot throttles for speed control that can be included with the kit. Here are photos of our foot pedal options. We also have a wire pull throttle that can be used with the car's existing gas pedal if you would like to keep the original gas pedal.


The THR-89 and THR-91 foot throttles are designed to mount onto a flat floorboard and I notice that the floorboard on the mini model T car is angled upwards where the throttle is. So these foot throttles may not work very well at that floorboard angle and be too vertical at the zero throttle position to be able to comfortably use. You might want to consider using the wire pull throttle and the existing gas pedal if it looks to you like the foot throttles will not work very well with the angled floorboard.

All this looks good and I understand about the foot throttles.  The only hang up is the less than 5mph top speed.  Is there any way of keeping my axel sprocket and chain and getting more speed?

My sprocket does have 54 teeth. ( I counted) and it seems to me that it's 1/2 inch between the pins, so my guess is that it's #40 chain, but I don't know for sure.


Since the chain has a 1/2" pitch and is wider than 1/8" it is obviously not a bicycle chain, so it has to be either a #40, #41, or #420 chain. #41 and #420 chain are identical except for their pin size, and #40 is identical to #41 and #420 except its roller is slightly larger in diameter. The standard for go karts is #41 and #420 chain so I believe that it would be safe to presume that the chain is #41/#420 size since the car is built with go kart parts.

We do not carry any motors that sprockets for #41/#420 chain will fit onto other than gear motors, which would provide a 4 or 5 MPH top speed when used with the existing 54 tooth axle sprocket.

An industrial 1.5 horsepower 36VDC 1800 RPM motor would have a 7/8" shaft that a common #41 sprocket will fit onto and would provide a top speed of around 15 MPH when used with the existing 54 tooth sprocket. This type of industrial motor costs around $600 though. Our controllers, batteries, and other parts will work with this type of motor.

Another less expensive option would be to use one of our 1000 Watt MY1020 motors and have a 96 tooth sprocket custom made for the rear axle. A custom made 96 tooth sprocket would probably cost around $100 to have made so this option would cost a lot less than using an industrial motor.

Thanks for sticking with me on this.  I see how easy it would be to use that 600 watt gear motor, but we are going to need more than >5mph to keep up with parades.   I will check with to see about having a 96 tooth sprocket in 8mm made, but before I do I want ask about having a machine shop weld a #41 sprocket to the 8mm sprocket that is on the MY1020.  Could this be a practical solution to my problem?

Welding a #41 sprocket onto the 8mm sprocket that is included with the MY1020 motor sounds like a great idea to me. The MY1020 motor's 8mm sprocket is made from steel and most #41 sprockets are made from steel also so they should be able to be welded together. The 8mm sprocket can be removed from the MY1020 motor for welding so the motor does not overheat.

You would just need to use a #41 sprocket with a larger bore such as 3/4" so a socket wrench could fit inside of it to tighten the bolt when reinstalling the welded together sprockets back onto the motor. I searched online and found that #41 sprockets with 3/4" bores are fairly common.

The nut that holds the 8mm sprocket onto MY1020 motors is a 13mm hex nut and most 13mm sockets are in the 18-19mm outside diameter range and will fit inside of a 3/4" bore sprocket.


We have three practical solutions.

1- can make a 96 tooth sprocket for 8mm chain for $70.  The sprocket would be 9" inches in diameter which would be good.  I then use your MY 1020 motor and everything is groovy....right?

2- I get an industrial motor for $600 that can take a #41 sprocket and use my existing sprocket and chain and your controller, throttle and batteries....right?

3- I get a #41 sprocket welded onto your MY 1020 motor and save myself around $350 -$400....right?

Putting aside the additional cost of the industrial motor, does it have advantages over the MY1020?

Will it give me something for the money?

An industrial motor will work with our controllers, throttles, batteries, switches, and other parts. A 1.5 horsepower industrial motor typically weighs around 40 pounds compared to a MY1020 motor that weighs around 10 pounds so it is quite a bit heavier. The advantage of an industrial motor is that it should last longer than a MY1020 motor since it is made for 24/7 industrial use as opposed to the MY1020 motor which is made for consumer use. For your application though a MY1020 motor should be more than high enough quality. I would only recommend an industrial motor if nothing else would fit, or if the car would be used all day long everyday of the year such as at an amusement park like Disneyland. If you are only going to use the car once in a while then the industrial motor would probably be a waste of money though.

A #41 sprocket welded onto the 8mm sprocket that is included with 1000 Watt MY1020 motor, and a custom made 96 tooth axle sprocket is definitely the most economical way to go so long as the axle sprocket can be made and the motor sprockets can be welded together.

I'm going to dismantle my kart and take the existing sprocket off to see exactly how it is attached to the axle.  I'll then order the sprocket for 8mm chain from 

Please put together a motor, controller, throttle, battery package for me.  I want whichever MY1020 motor you suggest.  If the 8mm sprocket doesn't work out, then I can have a #41 sprocket welded to the 1020's 8mm sprocket and use my old sprocket and chain.  What do you think?

What about using your 8mm 74 tooth axel sprocket? #spr874 .  I believe the speed calculator showed 19.36 top speed.  Is there an advantage to using a 96 tooth sprocket?

I just realized that if a 10 tooth #41 sprocket is welded onto the 8mm motor sprocket with a 3000 RPM motor and used with the existing 54 tooth axle sprocket that the gear ratio would be fairly high. The gear ratio calculator shows a 26.53 MPH top speed with this setup which is too high of a gear for a 1000 Watt motor carrying a 500 pound load. The largest #41 go kart sprocket I could find has 60 teeth which would bring the speed down to 23.88 MPH however that is also too high of a gear for the motor and load. So with a welded-on #41 motor sprocket it looks like a custom sprocket would need to be made for the axle in order to bring the top speed down to a reasonable level.

Regarding using a 74 tooth sprocket for 8mm chain with a top speed of 19.36 MPH that is a reasonable top speed on flat ground for a 1000 Watt motor and it might work good, however if the car will be used in parades and be driven fairly slowly for extended periods of time then I am a little concerned that the motor will be lugged and overheat with this high of a gear ratio. It might work good at lower speeds with this gear ratio though, it would take testing to determine. I would feel more confident with a 10 to 15 MPH top speed for a 1000 Watt motor powering a 500 pound load.

I will start working on the kit for this project. Which throttle would you like included with the kit?

I'd like the wire pull throttle, so I can use my existing gas pedal. did say they could make a 96 tooth sprocket for the 8mm chain, so it looks like that would be the best way to go....right?

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