Fixing up an old go-cart

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I bought a neglected, beat-up go cart designed for what appears two small kids, as the steering wheel and the place where the pedals belong are inconveniently located toward the left of the frame, like a car. It also has a very wide seat (aka an old piece of wood pilfered from tech theatre). Anyhow, this thing basically was a filthy, somewhat rusty frame containing nothing but the steering wheel and mechanism, front wheels, and a rod in the back for the brake. So I went and fabricated or bought parts as needed to prepare it for the addition of an engine, which is currently a 3.5 hp edger motor. It does "work" but I have had a TON of trouble with the chain, which was too loose and flew off. To combat this I shortened it by a link, and this made it too tight, but not so that it wouldn't run. As a result, I ruined the clutch, bent the engine mounting plate and burned a gallon of gas in one day. It seems like there's no 'in between' where there's just enough slack so that the chain stays on and isn't so tight that the back wheel (this is a dead axle go-cart) won't turn without force. I've tried moving the engine about on its mounting plate without success and I'm probably going to buy one of those half-link things.

That's it for the background info; now for the questions:

1) This vehicle has a 72 tooth gear on the drive wheel and a 12 tooth gear on the cutch; will reducing the amount of teeth on the drive wheel gear make any difference in speed? I'm curious as to how few teeth on the gear there can still be and have enough force to get the cart moving from standing still. Fewer teeth = more speed, right?

2)If the back wheels are larger (in this case I think they're actually thicker, not taller) than the front, what impact on performance does this have?

3)Is this thing worth my time and money?

I'd like to get this done before I get my driving licence (just turned 16) in August...

After that, I have a car and can't really enjoy it as much. But I suppose it'll make a nice present for my younger Brother.

Thanks,

Tim in Iowa

-- Tim R. (tim87529@email.com), June 30, 2003

Answers

For your motor problem try sloting the holes and ajust the motor where you want it. or buy a pulley with a spring to tighten up the chain. A>1. reducing the teeth on your drive wheel would make it faster but it will reduce your force (torque) that the motor would give you. its all about gear ratio. A>2. Thicker back tires mean better traction but also means more work for your engine. A>3. yes it is worth it. your almost homefree with it just a few bugs to work out and when you get your licence buy a trailer for your car and you will be able to bring it to much better places and have a blast!!! HINT HINT!!! I am 30 yrs old and had my licence for over 10 yrs and you can do more things with a gokart than a car. (legally) Also you might want to get a bigger engine for it i would suggest (9hp) runs faster I got mine upto 30mph

-- JAMES (thismonstersfriendly@yahoo.com), July 01, 2003.

I've tried moving the engine about on the plate (which has slotted holes) but I don't notice a difference in tension.

Would putting a smaller gear on the go-cart have any undesirable / easily noticeable unwanted effects on operation?

Traction isn't an issue here so I'll get thinner wheels.

-- Tim R. (tim87529@email.com), July 01, 2003.


Dear Tim, As someone said in a earlier response switching the drive sprocket will lower torque. It is worth doing though as you may not be able to take off from a stand still as quickly once it starts moving you got it made. I curently own a red fox lxt. I switched out the engine with a Honda 16 hp. I STRONGLY SUGGEST you at least put a 6 hp engine in your go cart especialy if you are going to be messing with the gear ratio! I have a 9 tooth sprocket going to a 24 tooth and with the Honda 16 hp I have no troble with torque. I also put tires off of an old cub cadet lawn mower in the back. it rides alittle rough once you do that so if you do reinforce the frame!!!

Robert K. from Missouri

-- Robert K. (bobeq@hotmail.com), July 24, 2003.


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