Even though most karts typically use a horizontal axle motor, it is possible to fit a vertical axle lawn mower motor with a few modifications to give your little car its full power. Enjoy the speed, freedom and intense joy of the road once again by transforming your old lawn mower into the kart of your dreams.
Method 1 of 6: Remove the engine from the mower
Step 1. Drain the oil
Depending on the engine you are going to use, you will need to equip yourself with a pair of pliers to disconnect the spark plug in order to drain the oil into the engine. Use a suitable container to collect it and avoid getting it everywhere.
It is best if you take it out while it is still slightly warm, as it will be more runny than when it is cold
Step 2. Empty the gasoline
Undo the gasoline hose clamp before starting. You can find it by walking up the pipe from the engine to the outlet of the tank. Note the location of the pipe on the carburetor. Take a pair of pliers and undo the collar to slide it along the pipe. Now you can detach it and empty the gasoline into a bucket.
Step 3. Find the connection with the accelerator
Usually you will need to find it under the carburetor. There should be a cable connected to the throttle and if you remove the screw that holds it in place you can easily remove the connection.
Step 4. Find the starter
It sits on the side of the motor and it will be shaped like a small can. On lawn mowers with an electric starter, it should be connected to a battery with a red wire. Use an adjustable wrench to undo the cable connected to the starter.
Step 5. Take out the necessary nuts and bolts
The mower motor is usually mounted on a base. Take a wrench to unscrew the bolts and another to hold the nut underneath while holding the gear in place.
Step 6. Take out the drive belt
You will find it on a pulley installed on the crankshaft under the engine. Lean it forward a little and pull the belt out of the pulley on which it is installed.
Step 7. Take out the motor
Grasp it firmly in your hands, lift it out of the mower and carefully set it aside.
Method 2 of 6: Prepare for installation
Step 1. Measure the size of the motor
You are going to need a kart frame that can accommodate the motor depending on its size and weight. Most five to seven horsepower engines should fit in a standard frame. The vertical axle motor can come from a mower that you ride or push, both of which will work on the go-kart.
The larger 13-22 horsepower motors that you can find on some mowers you have to ride on could destroy the drivetrain or kart
Step 2. Find a suitable framework
You should choose one that properly supports the vertical axle motor and mower gearbox. The latter must have a non-transverse axle arrangement.
Step 3. Draw a plan
Draw a full-size plan with chalk. This will give you a better idea of the correct dimensions for your frame.
Most of them should have a base that is between one-third and two-thirds of the base of the kart's wheels, but larger models will give you better stability
Method 3 of 6: Assemble the frame
Step 1. Cut out the bumper frames
Drill the holes for the padding of the tubes. You need to round the edges of the bumpers by connecting the vertical pieces that will hold the frame and the horizontal piece parallel to the rear piece to the frame with a short 22 degree cut. Drill holes in the tube padding on the back of the bumper.
Drill 3mm centered holes in the bumper padding 3cm from the end
Step 2. Install the axle
Cut a piece of square tube 2 x 2 cm and solder the ends. You are going to put a 15 cm bolt on the driver's side and another 10 cm on the passenger side. Weld the axle under the base of the frame.
Always use appropriate protective equipment during your welding work. If you don't, you could seriously injure yourself
Step 3. Install the floor
A 16 gauge metal plate should suffice for the floor of the kart. Use the plans drawn earlier to drill holes in the plate and screw the seat into them later.
Step 4. Weld the seat bracket
You need to install a bracket on both sides of the kart frame made of 2mm thick flat steel. This is where you will install the seat.
Method 4 of 6: Assemble the steering column, fasteners, and spindle brackets
Step 1. Cut and install the steering column
You need to cut out a 2 x 30 cm section of tube and weld it to the clips. Insert a 2 cm spacer on the axle near the steering hoop, sanding the axle a little towards the hoop if it is too tight. Drill three holes, spacing them the same distance from the center of the seal at the end of the axle.
Step 2. Cut the steering hoop and switch bracket
Make sure the cuts are at a 39 degree angle to the hoop. At this time, you need to verify that all measurements for the steering assembly are correct to allow your kart to turn properly.
The roll bar and axle should be at a 90 degree angle to each other
Step 3. Add fasteners for the brake and throttle
These 5cm long, 4mm diameter clips allow the pedals to stay in place and point forward. The clip closest to the center of the frame should be attached a maximum of 1 cm beyond the cross piece to which the steering column is attached. The second clip should be installed 1.5 cm from it.
Step 4. Attach the spindle supports
You need to weld them on the front axle of the kart. The spindle should leave about 2cm of space above the front axle.
Step 5. Install a footrest
Use a 4mm rod that you secure to a vise to bend it with a hammer into the shape of the passenger footrest. This will allow you to have a support on which to put your feet.
Step 6. Don't forget the nail for the band brake
It will act as a pivot for the band brake. Weld a 4mm round bar to the frame 4cm from the axle.
Method 5 of 6: Assemble the motor mount, brake rod, and accessories
Step 1. Install the motor mount
Make sure the openings for the motor mount allow the motor to slide forward slightly, then install the mount in place. There are no dimensions included for this step, as the size of the bracket will depend on the size of the motor.
- The motor support will be welded during the last kart assembly step.
- The stand should be able to hold the lawn mower engine level.
Step 2. Secure the throttle cable tie
Solder it about 10cm from the middle of the hole in the accelerator pedal at a 45 degree angle.
Step 3. Install the clip for the brake rod
Take it and insert it through the clip, bending it to fit the band brake. Then take the tie with the rod inserted in it and weld it to the kart.
Step 4. Shape the brake rod into the correct shape
Bend this 6mm rod at an angle that allows it to touch the brake pedal assembly. Cut it to the required length and weld the eyelets to the rod with a return spring installed at the brake pedal.
Step 5. Install a seat
Most kart kits do not screw the seat directly to the machine. If yours does, use a simple frame and screw it into the seat frame. It should be cut at an angle of 37 degrees and the backrest should be tilted at an angle of 105 degrees.
Step 6. Choose the side rails
There are many plans you can follow, but traditional side rails are formed from three pieces joined to form a rectangular rail with the side and back of the frame.
Side rails are optional on a go-kart
Step 7. Attach the motor mount and accessories
Once you have finished the body of the kart, you can now weld the bracket to the frame. When you have finished welding it, you can add the tires, seat cushions and other necessary parts to the kart.
Method 6 of 6: Install the vertical motor and gearbox
Step 1. Install the motor and gearbox on the frame
The location of the motor is not as important as that of the gearbox. To install the latter correctly, align it with the rear axle gear and secure it in place with bolts.
Step 2. Change the size of the gearbox pinion
The pinion is a toothed wheel inside the gearbox that controls the gear ratio for the transmission. You need to install a cogwheel of about sixteen teeth.
Step 3. Install the clutch
Use the mower's manual belt for the clutch. One end of the clutch must be connected to the engine on the side that protrudes from the pinion connecting it to the gearbox. If you don't have the manual clutch belt, you can purchase a centrifugal force one from an auto parts store that you can install on the go-kart.
The ratio of engine to transmission should be 1 to 1
Step 4. Secure the throttle cable
Attach it to the connection on the carburetor. You can now clean off the oil residue on the go-kart, being careful. You should always allow sufficient time for the parts you are working on to cool off, such as the engine or welds, before cleaning them.
- This simple go-kart should be perfect for the average user, although they might struggle to convert a vertical axle motor to a horizontal axle motor.
- Most go-karts use a centrifugal belt and horizontal axle motor, not lawn mowers. If you use the right motor, installation will be much easier.
- If you want to get a used horizontal axle motor, you can take a look at the classifieds to find industrial equipment for sale like kärchers, choppers, hedge trimmers and generators. These devices are usually equipped with horizontal axle motors.
- Wear all necessary protective equipment when welding, including a helmet, gloves, and tight-fiber clothing.
- Wait until the engine has cooled before refueling or oiling to avoid explosions and fires.
- Only go karting on your property in a specially equipped area. It is forbidden to drive on the road with a kart.