Wrong size tires, chain, sprocket or clutch??

[Breakhard]

I have a homemade 1" square tube go kart. It's 74" long and 36" wide, live rear axle, 4.10 / 3.50 - 5 front tires and 165 / 65 - 8 rear tires. The engine is a new, out of the box 212cc Predator. Has a 60T #35 sprocket and I've put both a #35 10 tooth and a #35 12 tooth clutch on. No matter what size clutch I put on, the clutch burns up about 1/2 mile down the road. Take off is very, very slow, but as I get going the speed picks up remarkably. But that doesn't stop the clutch from burning. Is the 5:1 or 6:1 gear not right for the size tires?? I've checked the disc brake to make sure it isn't dragging and am pretty well satisfied that it isn't, so that lead me to believe that the gear ratio isn't right. But...from everything I've read a 5:1 or 6:1 ratio is suppose to be about the best. Is the ratio with a live rear axle the problem?? Where have I gone wrong or what have I over looked. Appreciate any help.

[2SlickNick]

I am no expert, but maybe it is the live axle.
Torque converter might solve that. They are expensive. Justsuggesting. Hopefully someone with some experience chimes in.

[Breakhard]

Man there has to be another way to fix this problem. Torque converter came to mind, but didn't stay long when I started thinking about the $$$'s. Could change out the live axle to a regular axle?? Thanks for the response 2SlickNick.

[Masteryota]

Your gear ratio is too high, 10T clutch with 60T sprocket will give you 6:1, which is a tad on the high side, as most karts like 7:1, than you have to add in the tires, which I'm not sure the formula for adding that up, but it makes the ratio even higher. If money is the limiting factor, might I suggest a jackshaft?

[x-bird]

other than shorter tires or going to a 9T sprocket, i think your at the limit for a centrifugal clutch. they don't like tall tires. they're fine for short tires, but with the power level beyond 5 hp and a taller tire, you've hit beyond what they're really made for unless you get into some high dollar racing clutches. jackshaft and a 30-series Comet set up is probably you're best bet--and it'll cure the slow take off.

[Breakhard]

I've got an extra set of shorter tires that I'm getting ready to put on and been looking on the net for a larger sprocket. Found both 70 and 72t sprockets but hadn't seen anything about a 9t clutch. I'll look further. A 72t sprocket with a 9t clutch would give me a 8:1 ratio. So with an 8:1 ratio and smaller tires, maybe, just maybe I'll get this problem licked. Thanks for all your help guys. If you think of something else let me know.

[Masteryota]

I worry that by downsizing tires, and going with a bigger sprocket, that you may run into the sprocket getting real close to the ground. I would take a look at jackshaft kits from one of the many kart part sites, they aren't too expensive and allow you to change the ratio without sacrificing ground clearance.

[Breakhard]

Masteryota, you're right. I'm going break down and go with the jackshaft. This go kart project is going to have to wait for those parts to come it. Well, it was worth a try to get this thing up and running so I can flip it and not spend too many $$$$'s. Thanks guys for all your help. Breakhard.

[SLESTAK75]

You kart flipper!!!!!!

[Breakhard]

Getting ready to retire in October, so need something to keep me busy.

[zman007007]

come on over to my house I have plenty to keep you busy. LOL