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How can I mount a lawnmower engine to this RAD frame? Answered

I have this awesome frame and I want to know how to mount a lawnmower engine on it.  I'd appreciate a list of materials in you answer etc.
Thanks :-)


Lawn mower engines are in general expected to run at fairly low RPM - Although you can make them go faster it does them no goo at all.

A lot are also vertical shaft devices these days and unsuitable for your project.

You can buy small cc 2 and 4 stroke engines that have horizontal shafts at a fairly reasonable price.

e.g Northerntools



1 year ago

You can use the pulley method. People below are talking nonsense. Anything is possible. Use pulleys when you arrive at your 90 degree bend then go vertical and use pulleys at your two bottom bends. Use good bearing pulleys and you'll avoid friction. If you don't get what I mean then draw it out it will come together once you bend the v-belt at 90 you will know where to place the pulleys.

While pulleys will work like that, they will not do it under load. The belt either slips or snaps from stress.

you could go electric and get more power, no gas cost, and same price!

based on your pictures looks like you would need a horizontal shaft engine and judging by how far from center that sprocket on the rear axle is, you will need a gear reduction with centrifical clutch or just a centrifical clutch to get the drive chain out that far. Vertical shaft engines are difficult to use as you would have to have some sort of strong right angle gear boxes to transfer the power.

It also looks like you would need to have a better mounting plate for an engine. 1/4" plate would be more than enough and if you have a Honda engine, I believe the mounting holes are 8mm. You might be best off collecting some more materials and re posting the question as with this go kart, there is more than one way to skin a cat.

AFAIK, a lawn mower engine uses a vertical mount motor, and to use one with a go-kart requires a lot of customization (i.e. expensive, time-consuming). For this reason, most go-kart builders prefer to use a horizontal mount engine (where the shaft of the motor is horizontal) like a tiller uses. So you may want to rethink your plans.

I just read your update... I still think that using a lawn mower engine is going to be very difficult, because its more complicated than just "how do I mount it to the cart". The shaft on a lawn mower engine runs vertically (so the blade directly below it can spin), and you can't just place a lawn mower engine on its side because the engine was not designed that way, and it will fail to run properly. So, if you insist on using a lawn mower engine, you have to figure out a way to get a vertically mounted engine shaft to run your drive axel thats horizontal. This is precisely the reason why most DIY go-kart builds will use an engine with a horizontal shaft, such as a motorbike engine, a rotor tiller engine, a chainsaw engine, a mini-bike engine...

The speed you'll get is also determined by the go-kart's weight and the combined weight distribution.

I did a little research and found you some resources that you can use to learn what factors are important (at this point), and a couple calculators that you can use once you have all the specific points weighed. The whole process doesn't have to be complicated, but in order for your go-kart to run properly and do what you want it to, it requires a little homework...

Building a Go-Kart 

Rear Wheel Drive Assembly

Go-Kart weight Distribution (with calculator)

Go-Kart speed Calculator

I hope this information helps you. If you need more help, let me know.

I have the ability to weld
The cart w out the engive weighs around 60 pounds


6 years ago

Well, I don't think anyone can give you the information you're asking for without a lot more details from you. For example; what are the dimensions of the various components, can you weld or do you have access to someone who can, does the engine have a vertical or horizontal shaft and so on.
And, I'll throw in my two cents here: if the engine you are planning to use is a typical 3 to 5 horsepower lawnmower engine, you may want to re-think it. I'm guessing that chassis, including wheels, tires etc., weigh in the neighborhood of 200 pounds. Add the weight of the driver and you're looking at something around 350 pounds or more.
Put a lawnmower engine on that and you will have 3 year old kids on big wheels screaming at you to move over so they can pass.