[Kartbuilding] Fwd: my kart

Stephen Burke kartbuilding at gmail.com
Mon Oct 9 10:03:01 IST 2006

Hi Joe,

I know exactly what your problem is. 1/2 of it is the 22 inch rear
wheels - there massive.
You need to gear down those ratios.
If you have 22 inch rear wheels, you will need a gear ratio of 7:1 or 8:1.
If them wheels were only 12 inches (1 foot) then the gear ratio could be halved.

So twice the size of the wheels - twice as fast - twice the torque
required. Get the idea!?

Now a gear ratio of 8:1 (which you need !!) is fairly big to build up
with 1 set of pulley wheels.
I.E. you would need a pulley wheel on the rear axle 8 times the
diameter as the one on the engine.
You may need to use a idler axle inbetween the engine and the rear axle.
So from the pulley on the engine to a pulley, 4 times its diameter on
the idler axle. From this idler axle, a small pulley wheel goes to a
pulley on the rear axle - 4 times its diameter. This will build up ot
a ratio of 8:1.

Gear ratios is your problem.

Best of Luck,

On 7/15/05, Joel Mewton wrote:
> Howdy, I stumbled across your site as I was looking for some
> troubleshooting suggestions for my go kart. The problem is that it's
> big. I tried to put a comet centrifugal clutch on and didn't move six
> inches before it started smoking. So realizing the need for more
> power, I decided to go with a torque converter. It's not working a lot
> better though. The belt on that is slipping like crazy and I can't get
> the thing moving without pushing it and it still doesn't like to go
> too far. I am entertaining the idea of scouring the surface of the
> drive pully to get more grip on the belt but think it would tear the
> belts up quickly. And at $50 bucks a pop for the ones that fit my old
> torque converter, I'd rather not destroy too many. I also though about
> coating the pully surface with something similar to a rhino lining,
> basically some sort of rubberized material to improve grip as well.
> The rear tires of the kart are 22 inches in diameter and the whole
> thing weighs around 200-250 pounds completely assembled so it's not
> ridiculously overweight. The engine is a 11hp, 399cc briggs and
> stratton. If you have any ideas or suggestions I'd appreciate your
> help as I have been racking my brain on how to solve this this entire
> week. Sorry to bother you like this but I haven't found too many sites
> or forums on things of this nature and yours was one of the few that
> led me to believe you might know something. Thanks again!
> Joel

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