Noob Help Please

[jgreg07]

So i just bought this frame from a guy. Everything you see, minus the engine. I mounted a 420cc Predator motor on it. My clutch game in today. 1" clutch 40,41 chain. So i mount the clutch, add the chain, crank up the engine, give it some gas...and the clutch starts to spark and making a sound. The go kart barely moved lol So my question is, is my gearing that awful and or are those tires to dang big? I thought this motor would be able to handle this weight and setup. I thought this would be a quick little project, not taking everything into consideration i guess. Hence, all the thing needed was a motor, chain and clutch....yea so please let me know anything you got (dont beat me up too bad)! I was super excited when i got home from work to fire it up...:/

 

[chancer]

Not trying to beat you up: Is there a key holding the clutch to the crankshaft. I Ask cause they are usually built into the clutch, but maybe not on a 1"?

 

[jgreg07]

Yea there is one built in on the inside of the clutch. But its only like 1/4" long. The previous one i have for a different chain size had the key the whole length of the clutch. Weird

 

[jgreg07]

But it is def solid and set in that groove.

 

[crazykart]

Might just be that those tires/engine combo is too.kutch for a clutch. Whats your.tooth count on your clutch and axle sprockets? What size tires?
Is that clutch on backwards or is that just me? Hahaha

 

[chancer]

They can go both ways, Racers run them that way a lot.

 

[jgreg07]

40 tooth sprocket and 14 tooth clutch and about 18" tires

 

[jgreg07]

Yea i was about to say...someone told me it doesnt matter which direction lol

 

[jgreg07]

But i was thinking about that. And if i did swap ends, it wouldnt align with my sprocket :/

 

[crazykart]

If Im right thats a 2.8:1 ratio. Ya thats not going to work at all. Shoot for a 6:1 or get a TC. You could keep the clutch, find around an 80 tooth axle sprocket, and you SHOULD be ok...if I'm right lol.

I know chancer, I just always find it funny, and it freaks n00bz out when you say that lol.

 

[jgreg07]

Ok break that down for me even more. What exactly do i need lol that dang sprocket isnt coming off. The way its bolted the the axle and brake drum...thatll be hard for a replacement. im screwed lol

 

[jgreg07]

Ahh geeze TC. FML

 

[chancer]

First use the edit button, rather than post 3x.
and what he said except with 18" tires I think you need a torque converter. Clutches are only good to a max tire size of 15"
Where is Kartfab he knows about these big tire karts and torq conv.

 

[crazykart]

You're best bet is a torque converter tbh. Second is a bigger axle sprocket as you want it closr to the sizemof the tire, though idk if an 80 tooth sprocket would be bigger or not. You could possibly find a 6 or 7 tooth clutch but yoir cheapest option is the axle sprocket by far.

Right now for every rotation the tire makes the clutch makes just shy of 3, which with that big of tires will burn up that clutch before the tire ever moves.

IIRC you devide the axle sprocket tooth count by the clutch tooth count and that gives you your ratio. 6:1 is what most people would say is ideal, though for that probably 7 or 8:1.

More experienced members will weigh in and correct if I'm wrng or off.

Edit: I myself would spend the $100 on a TC from ebay and be done with it. All around its the best option.

 

[jgreg07]

I was looking at kits on ebay. Even a 10t sprocket would only give me a 4:1 ratio. Which isnt "ideal"

 

[crazykart]

Isnt ideal, and probably wouldnt turn the tires still. Imho you're gonna have to bite the bullet and get a tc, 40 series. Or drop your tire size and possibly jackshaft your kart.

 

[jgreg07]

yea thats what i mean. In that TC Kit the teeth on that sprocket is 10. Or does that not matter because of the belt? I am def going to be going with the TC and probably dropping tire size

 

[crazykart]

If you go with a tc you wont need to drop tore size I do believe. No I dont think it would matter all that much I think a 4:1 ratio with a TC would be fine.

Would give you a top theoretical speed of 48 mph. Not too shabby.

 

[jgreg07]

Niice. I will do this and update you guys with a pic when i am done. Thank you for the help and knowledge!!

 

[2SlickNick]

Just curious, but is that Clutch rated for that much hp?