Centrifugal clutch and gear ratio question

[SIMPLEARKANSAN]

I installed s 10 tooth Max torque clutch on a predator 6.5 hp(governed and no mods) with a 54 tooth rear sprocket. The tires are 13x5.00-6. After the break in period of the new engine, I had my 60 lb son take the kart for a very conservative first run. My questions are: 1. Is my gear ratio correct and 2. There was a small amount of smoke from the clutch after stopping. Could the smoke be from paint on a new clutch or burning off shipping oil. The clutch wasn't glowing red and I forgot to feel for excess heat. Again, it was a very small amount of smoke that quickly dissipated. Thanks for your help

 

[OzFab]

It sounds a little under geared; a 60t sprocket would be better...

 

[landuse]

As long as the kart is not too heavy, I think the smoke was probably just because the clutch was new. What is it like taking off? Is it really slow, or is there some decent pull?

Your ratio at the moment is 5.4:1, which is slightly high, but with small tyres and not a lot of weight you should get away with it. I would just keep an eye out on the clutch to see if it starts discolouring from heat, or smokes a lot

 

[SIMPLEARKANSAN]

It takes off like a rocket. I didn't apply any oil to the clutch as some have suggested and it had been stored in a cardboard box, which I read would suck up the oil like a sponge. Do you think I should apply some oil before the next use?

 

[Doc Sprocket]

You're probably okay- Best bet is another drive, this time feeling for heat. Watch for paint discolouration, too.

You should apply 2 drops of clean engine oil to the bronze bushing, and again after every couple hours of operation.

 

[mysteryboy28]

make sure your chain isn't super tight. should be about a half inch or so of wiggle room. a tight chain will ruin the centrifugal clutch very quickly!

 

[SIMPLEARKANSAN]

Thanks for the advice. I'll double check the chain. The kart is a Streaker without a cage, so I don't think it's considered real heavy. It's pictured in one of my earlier posts.

 

[anderkart]

a very conservative first run.

That might be why the clutch got hot enough to smoke a little. When you ride around at low speeds, the clutch is constantly slipping and building up more and more heat caused by friction between the clutch shoes and drum. Your clutch will say much cooler if kart gets right up to the speed/rpm where you can feel (and hear) the clutch is fully engaged/ not slipping.

 

[SIMPLEARKANSAN]

I think I may have found the problem. Chain was too tight and I applied a small amount of oil to clutch. I weight 215 lbs and i rode it around the neighborhood and no smoke and I could still lay my hand on the clutch.

 

[mysteryboy28]

as anderkart said - if the clutch isn't fully engaged, then there is a ton of friction causing a lot of heat. try to limit slow riding and stopping and starting a lot. accelerating on grass or a slight incline will be bad for the clutch too. try to get up to speed before riding on grass or small hills. your clutch will work better and last longer.

 

[SIMPLEARKANSAN]

Thanks again for your help.