WTD: Cheap engine for go cart

[Dirtydog]

Howdy folks,

decided im going to build a couple of go carts as i have quite a few of the family coming down for christmas, one for the older kids and one for the youngins.

i have two 4 wheeler frames, ones been cut up, and modified to be the older kids go cart, the other is made from box section, with steering componants from the other 4 wheelerz and tyres off an old ride on lawn mower.

im looking for something between 3-8 hp for the little ones, going to be running a pulley setup, with a idler pulley attached to a lever as the clutch, or if i can find a cheap enough centrifugal clutch engine.

for the larger one i am looking for a bike engine, hopefully around 200cc, or a 2 stroke 125 with a decent powerband. also a bike brake master cylinder that works, and the lines.


the frames are suzuki king quads, so anything from them i will look at too.

cheers for any help.

[Swamped]

I use mower engines and mower frames. easy to gear up, plenty of pony and provided they aren't totally abused the stock driveline holds up ok. If you don't remove the governor you want to tie the lever back.
The most common engines are 28ci sidevalves which are 460cc. I've been given them in the past as they would just be scrapped.
If you go a bit further you can end up with something like this:


I built one with a tf125 engine in it and it was ok for little kids. no powerband but you also didn't have to rebuild it each time you blinked.

[Dirtydog]

i was going to use a ridon frame and driveline but i found these for free, and the one i was going to use didnt have suspension, did grab the front wheel/axle and back tyres though.

i might even go for a bigger engine for the bigger one, its got a chain drive rear axle, but dont want a big engine other wise it will be too long and not wide enough.

fronts heavy enough that i can mount motor over rear and not affect weight bias too much.

[Swamped]

Suspension is just something more to go wrong and makes the build more complex imo.
The one pictured has a 575cc twin. When geared for it, it will easily run out over 80kmh and it has no suspension
Steering is all cloned off a grass cart. I messed with a quad and found it too restricting with the frame. Mowers just have a flat stamped pan or can have 2 runs of channel making it easier to use any axle and other driveline bits you want.

Underneath of another I built looked like this. You wouldn't need to reinforce yours like this one but more to see a possible belt clutch and the space you have to work with.

[Dirtydog]

man that looks like alot of fun.

and at 80k its quite fast too lol

the place we are going to take it there is heaps of potholes etc,

but i may build one like that aswell, i suppose its good practice for building 4x4s etc working out steering and drive train issues etc.

i eventually want to build a dunebuggy with a rear mounted engine, so toying around with different suspension ideas.

by the looks im guessing that you were into racing of some sort? id love to get into to something like that on a small scale, i thought of racing carts but they are quite expensive. and restrictive on what you can do with them..

do you know of anything around southland?

[Swamped]

Nah theres very little racing of those 'mowers'. they run grass karts down there which are cheaper to build and run than the tarmac models so maybe thats why people havn't really had a go. A lot of em would be as fast as the karts. Could look at this link.
http://www.grasskarting.org.nz/
A mate from invercargill used to race em and said the rules weren't nearly as strict as normal karts.

I've driven up a gravel farm track and you wouldn't want to go on anything rougher than that. Ya teeth would fall out.
I only built a few cos they're CHEAP and its cool to have a mower wheel walking
Might cost me 4 bux fuel for a day racing and they're made of what most people just turf anyways.

[Dirtydog]

thats what got me into making a go cart to start with, and i love the idea of rat rods, plus, anything free is a bonus lmao

[Dirtydog]

managed to get a ride on rear diff today, so lawnmower engine will be awesome.

[Swamped]

The gbox diffs last ok IF you run gear oil in em. The MTD 2 speed job is the other I've seen and they don't like abuse. I've seen em poo themselves just mowing the lawn.
I run a right angle box in one - ie raid a fert spreader; the other has a peerless 700 mower gearbox in it.

[Dirtydog]

might look into that for the larger one, but it should be fine on the smaller one wouldnt it?

id say if anything i will be underpowering it, dont want it to go too fast as 8-12 yr olds will be riding it.

as for the other one, i think it will be around 14-20 yr olds. maybe even older lol.

[Swamped]

Put a right angle in the older kids one and the gbox in the slower one. IF you had a free to a good home mower that you could drive (most have rotted out decks) just swap the pullies to gear it up and your done.

[Tarmac]

Track karts are a cheap way into motor sport but grass karts are a lot less, even only with a 250 4stroke they still go well and sideways for grown ups (unless ya fat) and I wld say go the briggs reel mower motor n clutch for the kids

[Dirtydog]

sounds good, grass karts look like heaps of fun.

ill have a look around for a right angle drive but i think it might be easier with a bike engine, as they already have clutches and gear set up, and the rear diff is chain drive anyway, so its really just up to putting it in place and getting a chain that works.

found out the diff/gearbox is an auto one with fwd and reverse, so that will come in handy for the kids to play around with.

might have found a cheap lawnmower for 1dollar researve, so will keep an eye on it but still looking.

[Dirtydog]

bumpedy

[Dirtydog]

bump

looking for motorbike engine that goes, and a lawnmower engine,

any considered. cheaper is better.

[Dirtydog]

Nothing at all?

been keeping an eye on trade me but havnt found much in the area