Introduction: Stock Go-Kart Conversion to Electric Power
A wanted to find a regular full-size go-kart for my older grandchildren but I did not want to mess around with a gasoline engine. In this InstructableI will show how to convert an old gas-powered go-kart into an electric powered go-kart. I think it will be much cleaner and less noisy and safer for them to use. I have had some practice working with smaller electric motors on some other mini go-kart projects I have made.
Supplies
See the attached PDF file.
Attachments
Step 1: Finding an Old Go-Kart Frame
I was able to purchase an old go-kart frame locally on the Marketplace App. I paid $120 for it. It was in pretty bad shape but did come with the axle and drive sprocket, spindles and old tires and rims. As I came to find out, it was a go-kart model called a “Dingo” manufactured by Manco Products, Inc. of Ft. Wayne, Indiana. I guess the company filed for bankruptcy in 2002. I was able to locate the serial number: 1469256. I was also able to locate an old parts manual that showed a schematic of the go-kart assembly. This helped greatly in the restoration.
Step 2: Disassembly
1. First, all 4 tires were removed. One lock nut held each tire on their axle. The tires were severely worn so they will have to be replaced.
2. The bolts for the rear axle bearing flanges were removed and the axle was dropped and removed from the frame. The bearings were shot and will have to be replaced.
3. The drum brake was removed from the axle and found to be severely rusted and coming apart. This will have to be replaced also.
4. The 1” diameter axle seemed to be true and in good shape. I was not able to remove the drive sprocket (welded or rusted on) so I decided to keep it on and reuse both the axle and the drive sprocket.
5. I removed the two tie-rods. They appeared worn and bent so they will need to be replaced.
6. I then unbolted and removed both spindles. They appeared to be straight and intact, but I decided to replace the old, rusted springs.
7. Both pedals were unbolted and removed.
8. Lastly, the protective side bars and front-plate were removed. There will be reused.
Step 3: Restoring the Frame
Once everything was removed, the frame could be cleaned up and repainted. I won’t spend a lot of time going over this since I just used standard metal restoration procedures you would use on a metal car or bicycle. I want to spend more time going over the electrical components used on the go-kart.
First, all grease and grime build-up was removed. Most of the old paint was removed with some paint stripper and a wire brush grinder wheel. Next, a rust remover was brushed on. I used a brand called Rust-Oleum Rust Dissolver. I used a wire brush and some elbow grease to remove a lot of the rust. All the metal appeared structurally intact. I then placed a metal preparation solution on the frame made by POR-15.
It was brushed on and allowed to work for 15-20 minutes and then rinsed off completely with a garden hose. I then allowed the frame to dry completely in the sun. A black Rust Preventive Coating made by POR-15 was then brushed on in two thin coats.
Now the frame was ready to paint. I suspended the frame in my garage and first used a gray primer to hide the black rust barrier. I then used multiple thin coats of standard Rust-Oleum spray paint to give a nice new look. I also painted all the parts I had removed and will be reusing. I used a paint color called “Ford Tractor Red”.
The brake and gas pedals were painted a metallic silver color. The steering wheel was painted a semi-gloss black color, but the middle hub was covered with painter’s tape. I wanted to maintain the original “Dingo” logo. All parts were allowed to dry thoroughly. I even kept some electric heaters running in my garage so the proper temperature would be maintained to cure the paint properly.
Step 4: Reassembly – Part 1
I first reattached the steering wheel with the original ¼” diameter bolt and nut. Then the new seat was bolted in place with (4) ¼” diameter x ¾” bolts. Next, I reattached the front spindles. This was a lot harder than I thought it would be because the new springs were very large and firm and did not fit inside the spindle bracket on the frame as they were.
I finally figured out how I could compress the spring so it would fit inside the spindle bracket with the spindle. I put the spring in a bench vise to compress it down and then held that compression in place with strong picture frame wire. Please see the photos. Once the long bolt was placed through the bracket to hold the spring and spindle in place, I cut the wire ties with a wire cutter and removed as much of the wire as a could.
Now the new tie-rods could be attached. These were new 3/8” diameter tie-rods with 3/8” diameter end openings. I used a 4-foot-long level as a straight edge that was secured at a right-angle to the midline of the frame. This helped me maintain the spindle axles in their correct position as the new tie-rods were fitted and secured in place with 3/8” diameter bolts. Please see the photos.
The pedals were much easier to attach with the original 3/8” diameter shoulder bolts. One bolt went through the frame tubing with the corresponding limiting bracket to secure each pedal in place and act as the fulcrum for the pedal.
I needed to divert from reassembly for a time to mount the new 2000-watt electric motor. This would be the first electrical component to be placed on the restored frame and was one of the most critical steps of the go-kart conversion. First, I temporarily position the axle in place with the attached drive sprocket. New bolts were used with the bearing flanges to hold the new bearings in place around the axle.
The original drive sprocket was ¼” thick and made for a #420 drive chain. The problem was that the electric motor came with a small size shaft sprocket that functioned with a small #25H chain. The key to being able to use this electric motor on the go-kart conversion was to find a motor shaft sprocket of the correct #420 size and diameter for the shaft. Fortunately, there is a company on the web selling the exact sprocket I needed. The company is called ElectricScooterParts.com. The link is provided here:
Motor Sprockets for #40, #41, and #420 Chain - ElectricScooterParts.com
The sprocket was called a “10 tooth 10mm Double D-Bore Sprocket for #40, #41 and #420 Chain”. The new sprocket was switched out on the motor shaft and bolted in place.
Now the motor was positioned so the new sprocket on the motor shaft was directly above the axle drive socket. Because the electric motor is so much smaller than a gasoline engine, I noticed the motor shaft was very low. Also, holes on the mounting plate had been pretty well hacked up through the years. For these reasons I used some 1 ½” square perforated steel tubing to mount the electric motor. Please see the photos. This raised the motor shaft 1 ½” and allowed for the motor to be firmly secured to the frame motor mount with (4) 5/16” diameter x 2” long machine bolts and lock nuts. I had to use some larger washers underneath the frame mounting plate to make sure the bolts were held firmly. This was all accomplished with the two sprockets perfectly aligned vertically. A straight edge was used to verify this.
The last step was to place the drive chain on the sprockets. The bulk chain piece was measured and sectioned one link short of matching up flush with a chain breaker. This allowed room for the master link to be inserted and secured. Any slight slack in the chain was then removed by loosening the engine mount screws and moving the electric motor slightly forward in the mounting slots. The screws were then tightened again.
Step 5: Drum Brake Installation
Once the motor was mounted in the correct position, the axle and bearings were removed again. This allowed for the brake drum and appropriate spacers and lock collars to be placed on the axle. Now the axle was lifted up again to the underside of the frame and mounted permanently. The new brake drum was positioned close to the left frame and locked in place with a ¼” x ¼” key and lock collars.
Once the brake drum was positioned on the axle, the new brake band could be positioned around the brake drum and attached to the left frame in the designated position. A 3/8” diameter x 3” long bolt, washers and lock nut was used to secure one end of the brake band. The other end was attached to the brake rod that ran forward to the brake pedal.
The new brake rod was made from a piece of ¼” diameter steel threaded rod I purchased at my local hardware store that was cut down to the correct length. The ends of the brake rod were adapted to attach to the brake pedal at the forward end and the brake band at the back end. I placed a ¼” diameter thread on the brake pedal end from the old brake rod (I had sectioned off) and used a modified ¼” diameter eye bolt to engage the drum band end. To complete the new brake rod, these modified ends were attached to the threaded rod with 2 coupling nuts. Please see the photos. Now when the brake pedal was pushed the brake band would constrict against the brake drum, and with friction, stop the turning of the axle.
Step 6: Adding Electronic Components - Part 1
The posterior aspect of the frame (behind the seat) had to be adapted to hold the electronic components needed for the electric motor. Plywood platforms were added to the frame to accommodate these components. This was the lightest material and the fastest way I knew to do this.
On the right side of the electric motor a ½” thick plywood platform was sized and cut to fit the frame. This plywood platform was mounted below the level of the frame with ¾” Rigid One-Hole Straps. These straps were perfect for grabbing the round frame pipes. Please see the included photos. This is where the batteries will be positioned and secured.
One the left side of the electric motor another ½” thick plywood platform was sized and cut out. It was shaped to go around the motor mount and provide relief for the top of the drum brake mechanism. This plywood platform was mounted above the frame with the same One-Hole Straps. I should mention that all straps were bolted in place with a ¼” x 1 ½” machine bolt, large washer, and lock nut.
With both the left and right posterior plywood platforms in place, I needed to make a chain guard before any electronic components could be mounted. Cardboard was used to make a back outline that would be wider than the motor sprocket and chain. This pattern was traced to 1/4" thick piece of plywood and cut to size and then mounted to the electric motor with (2) 6MM x 20MM machine screws. The chain cover was made to match the back piece and attach to the left plywood platform.
The left side is where most of the supporting electronic components are mounted. The motor controller was mounted directly behind the seat. The electronic terminal connection block (yellow) was also mounted on this platform. I followed the instructions that came with the motor controller to make all the electronic connections. The main connections to the terminal block are 5 cables that run from the motor controller and motor have to be matched up and secured with the provided washers and nuts.
Step 7: Batteries
With the right platform in place, I was able to find a battery holder for the four 12-volt batteries needed to run the 48-volt motor. I used Mighty Max batteries that can be found here:
Amazon.com: 12V 22Ah Baoshi 6-DZM-20 6DZM20 Scooter Bike Sealed Battery - 4 Pack : Sports & Outdoors
I bought a waterproof battery box that was marketed for marine use. However, I had to modify it. The front end of the box had to be trimmed a little bit to fit behind the seat frame. The posterior right corner had to be trimmed to fit the curve of the posterior frame. Auto body putty was placed to fill the resulting hole. The bulky top that came with the battery box had to be discarded once I shortened the height of the battery box and a new cover had to be fabricated to cover the modified battery box. I made this out of thin plywood and painted it black.
The four 12-volt batteries inside the battery box had to be wired in series. I soldered ring terminal ends to a thicker wire gauge to hook the batteries together. The resulting end positive and negative terminals were wired to a quick connect RV male plug that would fit into the receptable on the left posterior plywood platform.
For charging purposes, a quick connector was soldered between the second and third battery. After much research, I decided to recharge the 48-volt battery pack as two separate 24-volt batteries. Removing the connection between the second and third battery allowed me to use two 24-volt chargers to charge the first two batteries separately from the last two batteries. This would provide a more consistent charge for all four 12-volt batteries and a 24-volt charger was much cheaper than a 48-volt charger. With this charging scheme, the battery box did not have to be taken off the go-kart (it is quite heavy!). If for some reason the battery pack had to be taken off the rear platform (for transport), disconnecting the RV plug would make this a simple process.
Step 8: Adding Electronic Components - Part 2
The next electronic component to hook up was the speed or throttle device. There is a 3-wire connection for a throttle on the motor controller. There are electronic foot control throttles available to make this connection to the motor controller, however, I wanted to use the metal “gas” pedal that was already attached to the frame. The idea I came up with was to use a scooter handlebar throttle that was activated (turned) by a cable connected to the forward “gas” pedal. It is a little hard to explain but I secured the scooter throttle on a ½” diameter PVC pipe that was mounted underneath the right plywood platform. As the “gas” pedal was pressed, the attached cable made the handlebar throttle rotate to increase the speed of the electronic motor. Please see the photos. A hose clamp was attached to the scooter throttle to give an attachment point for the “gas” cable.
The last electronic component to fabricate was the dashboard. This would house the on/off key, the forward and reverse toggle switch, and the voltmeter. These were all connections coming off the motor controller. The electronic “transmission” or speed switch (Low, Medium, High) was mounted to the left steering wheel support (not included in the dashboard) since it had a circular type clamp already that was meant to attach to a scooter handlebar.
I decided to make the dashboard movable. I was going to attach it to the steering wheel brace, but I decided against this. The movable dashboard was made from a plastic electronic component box and tethered to the motor control with a ribbon wire bundle. Each dashboard control had to be connected to the matching plastic connector on the motor control. I used Glarks 2.8mm pitch Pin Wire Connectors with the appropriate plastic housing to match the motor control plastic connectors.
The correct diameter holes were drilled in the front plate of the electronics box to accept the switches. A rectangular hole was cut to match the dimensions of the voltmeter. I should mention that a third pushbutton was added to turn the voltmeter on and off. I discovered the voltmeter stayed on when the on/off key was turned off and I was afraid this would slowly drain the batteries.
I initially placed the movable dashboard below the steering wheel with 2-way carpet tape to the frame’s metal floor plate. If this position doesn’t work out it can always be moved (the advantage of a movable dashboard).
Step 9: Reversing the Electric Motor Direction of Rotation
I thought I was done with the electronic components of the go-kart conversion but there was one issue I didn’t foresee with the electric motor. The only spot where the motor could be mounted to drive the exiting sprocket on the axle was with the motor shaft and sprocket to the left (as you were looking at it from the rear). Most brushless electric motors come with a clockwise rotation so the motor, as mounted, was driving the axle in reverse. Fortunately, it was not that difficult to switch the motor rotation. These brushless motors are totally reversible on run properly in both directions. I referenced a U-Tube video that explained which wires to switch.
How to reverse DC electric motor direction for gokart - YouTube
There is a bundle of small wires and a series of thicker wires that run from the motor to the controller. With the smaller wires, you need to invert the yellow and green wires. That is, you can cut the wires and twist connect the yellow to the green wire and the green to the yellow wire. I then soldered the both twist connections and covered them with a heat shrink insulator of the appropriate size.
You do not have to cut the thicker wires. You simply switch their connection on the terminal block provided. You take the blue cable from the motor and connect it to the yellow cable from the controller and retighten the nut. Similarly, you connect the yellow cable from the motor to the blue cable from the controller and again, retighten the nut. The green, red and black cables stay the same.
You now have the electrical motor spinning counterclockwise to propel the go-kart forward. All the controller functions will work exactly the same.
Step 10: Reassembly – Part 2
As I stated before, the tires were worn and rotten and needed to be replaced. I used a Pittsburgh Mini-Tire Changer from Harbor Freight to remove the old tired from the rims. The bearings on the front rims were bad and rusted in place so I decided to just buy two new rims with the tires and bearings in place from GoPowerSports.com. These were 140/75 – 6 tires mounted on a 6” rim. The new rims were painted a metallic silver color to match the pedals.
The rear tires are much bigger and wider with an 8” diameter rim. These old tires were removed with the same Pittsburg Mini-Tire Changer. They were discarded and the new tires were mounted on the rims. The new tires are a size of 18x9.5 – 8. Then the rims were painted the same silver metallic color to match the front rims. Masking tape was used to prevent paint from getting on the tires.
Now the wheels were ready to be mounted on the go-kart. Spaces were placed on the axles to position the tires in their correct position at a safe distance from the frame. The front axle spacers had a 5/8” bore with a ½” width. The rear axle spacers were a 1” bore with an approximately 3” width. I cut the spacers from a 1” diameter galvanized pipe.
Step 11: Test Run
My grandchildren and son were able to test the completed electric powered go-kart.
Please see the attached video.
Initial results were mixed. The motor seemed to power the go-kart fine, but the steering and weight distribution were not correct. We came to the conclusion that there was too much weight in the back. The front wheels did not have enough traction to provide adequate steering.
Since the 4 sealed lead batteries weighed over 50 pounds, I decided to move the batteries to the front floor plate under the steering column. This would provide more weight toward the front of the go-kart and provide better traction and steering for the front tires.
Step 12: Relocation of the Batteries
The main battery holder had to be abandoned. It would not fit under the steering wheel. In fact, the 4 batteries barely fit on the floor plate. Light perforated angle iron pieces were used to hold and secure the batteries on each side. The dashboard fit perfectly in front of the batteries to secure the batteries in the anterior-posterior direction. A cut-down version of the wood battery holder top was used to fit on top of the batteries and cover the terminals. The top and batteries were then all secured with 2 nylon straps. Please see the photos.
Step 13: Second Test Run
The weight distribution seemed to be much better. Both my son and grandchildren found the go-kart easier to drive and steer.
Please see the attached videos. When first testing the Go-Kart, we had the motor set to Low Safety Mode. They are a little timid as they are learning to drive it but after a while, they were able to drive safely at a much faster speed with the electric motor switched to a higher mode.
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