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  Oct. 9, 2011 3:50 p.m. SVreX SuperDork

  I don't know a thing about carts, other than that there is a pretty reasonable condition cheap kid's frame sitting in my garage that my kids want to see run.

  We are talking one of those 5hp single speed kid's versions, not a nice shifter cart.

  I thought a lawnmower engine would be the quick solution, but then I realized carts have horizontal shafts, and mowers have vertical ones.

  OK, there are probably better engines, but I've got several decent lawn mower vertical shaft engines around, and would love to use one if I could figure out how to hook it up easily.

  I thought of a worm drive gearbox from an industrial skillsaw. Too small. I thought of a differential from a full sized car. That's silly.

  There's got to be a simple grassroots solution, or a source for cheap cart parts.

  Thoughts?

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  Oct. 9, 2011 3:55 p.m. fritzsch Reader

  There was a article in GRM back in the summer of 2010? I think detailing how to make cheap go karts from lawnmowers. If you want to use a vertical shaft lawnmower engine you are probably best off doing it through a used lawnmower transmission. I know in the article they were basically able to get all their parts from "lawnmower junkyards" Id see if there was anything like that near you. Small engine repair shops will probably have some mowers in various states of disrepair you may be able to get parts from.

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  Oct. 9, 2011 5:19 p.m. turboswede SuperDork

  Golf cart differential/rear axle. Hit the local Golf clubs, chat with the maint. guys.

  Rotate nose down to align with chain drive off engine.

  Use large enough tires to ensure proper ground clearance.

  Or rotate nose up and mount engine to the nose.

  Otherwise, maybe you could use a twisted belt solution to drive the rear axle?

  Some more ideas from The Googles:

  http://www.diygokarts.com/vb/archive/index.php/t-4766.html

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  Oct. 9, 2011 5:20 p.m. TRoglodyte HalfDork

  Minibike centrifugal clutch? Small engine shop would be your friend or go to a place that sells new karts and do some recon.

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  Oct. 9, 2011 5:54 p.m. SVreX SuperDork

  fritzsch wrote:

  There was a article in GRM back in the summer of 2010? I think detailing how to make cheap go karts from lawnmowers. If you want to use a vertical shaft lawnmower engine you are probably best off doing it through a used lawnmower transmission. I know in the article they were basically able to get all their parts from "lawnmower junkyards" Id see if there was anything like that near you. Small engine repair shops will probably have some mowers in various states of disrepair you may be able to get parts from.

  I like this idea, but any lawnmower engine I have is because the transmission was no good.

  "Lawnmower junkyard" doesn't make sense here (deep rural South). It's a little like saying "Ferrari junkyard".

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  Oct. 9, 2011 6:49 p.m. fasted58 SuperDork

  There's always some horizontal shaft engines on CL (ugh)

  Haven't searched in depth but might be worth a look at this site for discounted new, overstock and discontinued engines:
  

  http://www.smallenginewarehouse.com/ProductList.asp

  or maybe here:

  http://www.surpluscenter.com/item.asp?item=28-1658&catname=engines

  Lawnmower trans may make the cart pretty slow.

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  Oct. 9, 2011 7:02 p.m. 2002maniac HalfDork

  SVreX wrote: "Lawnmower junkyard" doesn't make sense here (deep rural South). It's a little like saying "Ferrari junkyard".

  I figured "lawnmower junkyard" would be more like "bubba's backyard"

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  Oct. 9, 2011 7:03 p.m. oldopelguy Dork

  Riding mower transaxles are almost always like what you are looking for these days. Get one with real gears and not hydro for reliability, or like your mower with hydro if your kids don't want to figure out gears.

  Look for "peerless transaxle" on your favourite search engine.

  Typically the trans has a 8-10" pulley on it, and the engine pulley is 4-5". Smaller on trans=faster, and plenty of room to go.

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  Oct. 9, 2011 8:54 p.m. Toyman01 SuperDork

  Harbor Freight has the 212cc horizontal engine on sale for $99. I think that equates to about a 5hp. That and a clutch will do you on the cheap. A gear box that will handle the abuse of driving a go-kart will probably cost more than that.

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  Oct. 9, 2011 9:03 p.m. chaparral Reader

  Dirtbike. Craigslist. Don't fool around. Think about what will happen if a juryrigged drive system locks up at full speed, then think about what the worst/cheapest dirtbike on Craigslist costs and how much scarier/more fun the kart will be with it.

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  Oct. 9, 2011 9:18 p.m. Toyman01 SuperDork

  chaparral wrote:

  Dirtbike. Craigslist. Don't fool around. Think about what will happen if a juryrigged drive system locks up at full speed, then think about what the worst/cheapest dirtbike on Craigslist costs and how much scarier/more fun the kart will be with it.

  

  Used to have a go-kart with a 125 2 stroke on it. It would smoke 1st, 2nd, and 3rd on the street in front of my house. Talk about stupid fast.

  That thing used to go through back tires like they were going out of style.

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  Oct. 9, 2011 9:37 p.m. SVreX SuperDork

  chaparral wrote:

  Dirtbike. Craigslist. Don't fool around. Think about what will happen if a juryrigged drive system locks up at full speed, then think about what the worst/cheapest dirtbike on Craigslist costs and how much scarier/more fun the kart will be with it.

  A drivetrain lockup at 10-12 mph wouldn't be nearly as bad as hitting a tree at 40-50.

  I'm with you on the "Don't fool around", but tell me again why I'd want "scary" for a 7 year old??

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  Oct. 10, 2011 6:15 a.m. bravenrace SuperDork

  The first thing you need to know about your cart is that it is a kart.

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  Oct. 10, 2011 8:34 a.m. failboat HalfDork

  Toyman01 wrote:

  Harbor Freight has the 212cc horizontal engine on sale for $99. I think that equates to about a 5hp. That and a clutch will do you on the cheap. A gear box that will handle the abuse of driving a go-kart will probably cost more than that.

  add a 20% off coupon to that and its $80 for a brand new engine.

  The old greyhound 196cc engines were 6hp, i have been reading the new 212cc engines are around 7hp.

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