My First Kart Project

[Motornerve]

So I know a lot about electrical engineering, a fair bit about welding, but not very much about motors. I am fairly mechanically inclined, however, so I thought I would give this a go.

I have a Craftsman 6.5 Horsepower 21' Mulcher
Model # 917.388519

I would very much like to construct a street Kart for fun and amusement. I realize it may take time, effort, and money, but I am certainly willing to put in the time, as this has been a project I have wanted to do for some time now.

Feeling a little overwhelmed by all the conflicting DIY guides out there, and hoping for some more situation specific advice.

Teach me, oh masters. Show me the first steps on my journey.

 

[souperman000]

welcome to the forum!

To start, it is much easier to have all the parts needed and a written plan/picture. Have you searched the forum for ideas or so you have a specific design in mind?

Is your mulcher engine horizontal or vertical shaft? you will want a horizontal for kart use.

 

[Motornerve]

As for the design, I really have no idea, I will look around the forums more. I was having trouble knowing how to correctly pick a design, mostly because I don't know what the pros, cons, and limitations of what I am trying to do are.

Also, how would I determine the orientation of the shaft? It's a lawnmower, if that's what your asking. So the shaft goes vertically down into the blades.

 

[Jonester 123]

Hello there welcome to the forum, here is a website that will help convert a lawnmower engine to work in a go cart. Hope it helps, www.gocartguru.com good luck

 

[souperman000]

Hello there welcome to the forum, here is a website that will help convert a lawnmower engine to work in a go cart. Hope it helps, www.gocartguru.com good luck

If this is his first build, I suggest he finds a horizontal shaft to use, instead of trying a conversion.

yea, you have a vertical shaft.

 

[Doc Sprocket]

So the shaft goes vertically down into the blades.

Then it's a vertical shaft. Not the first choice for powering a go kart, as you need a horizontal drive. You can roll the dice and try to convert the engine for horizontal operation*

Or use a 90* gearbox of some nature to convert the drive from vertical to horizontal.

Best bet, honestly? Source a horizontal shaft engine and go from there.

*Converting a vertical shaft engine to horizontal operation entails the following-

-Constructing an intake manifold that will re-orient the carb 90*
-Constructing an oil slinger for the connecting rod
-A method for sealing the oil fill correctly against leaks
-Understanding the intricacies involved in the fact that the governor will no longer work, and physically removing the governor internal parts.
-Adapting the output shaft to work with common, straight-bore, keyed drive components.

 

[Motornerve]

Hello there welcome to the forum, here is a website that will help convert a lawnmower engine to work in a go cart. Hope it helps, www.gokartguru.com good luck

This site actually looks like it has total conversion plans, as well as other things like specific boiler plate type plans that will greatly assist a new person.

I am going to give this a try and report back. May be a bit though.

 

[kendelrk]

Then it's a vertical shaft. Not the first choice for powering a go kart, as you need a horizontal drive. You can roll the dice and try to convert the engine for horizontal operation*

Or use a 90* gearbox of some nature to convert the drive from vertical to horizontal.

Best bet, honestly? Source a horizontal shaft engine and go from there.

*Converting a vertical shaft engine to horizontal operation entails the following-

-Constructing an intake manifold that will re-orient the carb 90*
-Constructing an oil slinger for the connecting rod
-A method for sealing the oil fill correctly against leaks
-Understanding the intricacies involved in the fact that the governor will no longer work, and physically removing the governor internal parts.
-Adapting the output shaft to work with common, straight-bore, keyed drive components.

These well define a good reason not to try it on your first build, but i pose one more reason. you would need to make a mounting plate that goes straight up for the engine to run

 

[Doc Sprocket]

These well define a good reason not to try it on your first build, but i pose one more reason. you would need to make a mounting plate that goes straight up for the engine to run

You're absolutely right, I forgot to mention the mounting headache!

Regarding the go kart guru stuff- I have perused that site deeply, and I have been thoroughly unimpressed. I wouldn't send a nickel that way... Without getting into the nitty gritty- I find that there is false/inaccurate/incorrect information in abundance there, as well as incorrect terminology. If it was just some dude saying "hey, I've got some go kart ideas for y'all", that'd be one thing. But a self-proclaimed "Guru" who is profiting, selling books and plans? Not acceptable to me. Sorry.

 

[Jonester 123]

I gather from what you guys are saying, the go cart guru site is crap information. I found it while i was browsing the internet, i have never done the conversion myself. Thought it might be good sorry.

 

[Doc Sprocket]

No worries. It does appear very informative, and not everything there is bullspit. That said, I still think it ain't what it's cracked up to be.

 

[OzFab]

Welcome to the forum motornerve.

Regarding design: you first need to consider where you'll be riding; pavement, grass, rough terrain. Once you've done that, the next step is to find a design that jumps out at you. Don't limit your search to this site, do a google image search.

Regarding the engine: Again, you have a choice to make; do you want this overall exercise to be easy or difficult? If you choose the former, get another engine that's already horizontally orientated. If you choose the latter then go ahead & have a go at the conversion.

At the end of the day, this is all about having fun &, if you're not having fun, you're not doing it right

 

[rwd4evr]

I just did some reading and fully agree with toystory. "guru" is talking real stuff and nonsense all in the same breath. dont give him your hard earned money.

 

[Doc Sprocket]

I just did some reading and fully agree with toystory. "guru" is talking real stuff and nonsense all in the same breath. dont give him your hard earned money.

Yeah- it's pretty crazy, isn't it? There is some serious, quality info there- along with a bunch of total crap. So- If you are uninformed enough to need all that info, you are uninformed enough to separate the good from bad.

 

[OzFab]

If you are uninformed enough to need all that info, you are uninformed enough to separate the good from bad.

Well, that makes sense