12hp gp kart

[grandam88]

i was just wondering what yall thought about a 12 hp go kart it a engine from a generator and yes it is horizontal shaft, i just recently got the 12 hp motor and frame with everthing for free from my brother in law all i have to do is get the clutch and chain, but im really herte to ask what gear ratio i should use. like a ragular ratio like 5 or sumthin. i dunno but i would really like yalls help on this one what im looking for is like fast acceleration like capaple of a burn out maybe but still a good top speed and still capable of riding on hills and stuff, thanks

[robertdjung]

hmm. that's a good question. I don't know if I've ever heard of such a big engine on a kart.

Have you measured the output shaft to make sure you can find a clutch for it? I know that northern tools sells a big one -- 1", because I've bought one there.

The best performance will be a torque convertor -- if you can find one that fits. Otherwise, I'd go with a 12 tooth clutch to a 60 tooth sprocket.

Problem with these engines is they generate the torque at high rpm -- but you can't immediately get high rpm's from a standstill... A 72 tooth sprocket is also available, that would give you better low end power.

[grandam88]

i think its a 3/4 shaft, im not 100 percent sure, but i really just wanna go with a clutch because their not in the 100's of dollars i mean they can be but a torque converter is just to expensive for me right now. but what i"m trying to ask is does anybody know where to get a 3/4 bore clutch that is go for the 12hp range. cuz every where i go either doesn't specify or is only up to like 8-10tops hp. thanks

[robertdjung]

Here's a 3/4" clutch (http://www.tkqlhce.com/click-1815552-10291266?url=http%3A%2F%2Fwww.northerntool.com%2Fw ebapp%2Fwcs%2Fstores%2Fservlet%2FNTE_CJjump%3Fstor eId%3D6970%26langId%3D-1%26url%3D%252Fwebapp%252Fwcs%252Fstores%252Fservl et%252FProductDisplay%253FstoreId%253D6970%2526pro ductId%253D16209%2526R%253D16209&cm_ven=CJ&cm_cat=1647616&cm_pla=1815552&cm_ite=Heavy+Duty+Clutch+With+Needle+Bearings&cjsku=1372%22) that they sell.

They say it's only good for up to 8 HP... I don't know if that means that it will just wear a little faster with more power, or what, but I'm going to use it on my 10 HP, put a saftey cover on it (like you always should) and just keep my eye on it.

[grandam88]

ok cool but what do you mean a "safety cover" the clutches ive seen look like they already have cover basicly. but thanks i was going to do this anyway i just wanted to see if there was a clutch rated at this. oh and does anybody know the power difference i mean like say like i have a 12 hp motor and a 5.5 hp motor that both turn 3600 rpm. what would be the difference like they are still spinning the same rpm. does this mean i can use a lower (higher torque) ratio on the 12hp and dtill have a good acceleration off the line and also have a higher top speed?

[grandam88]

oh yeAH I FORGOT they have way cheaper clutches that that other places on the web go look around

[Lead Foot]

You would want a higher ratio( bigger clitch, smaller sproket) on the 12 hp. This would give you simmilar acceleration with alot more top end. With the 12hp you can deffinatly gear it up.

[grandam88]

so what sizes should i get

[robertdjung]

ok cool but what do you mean a "safety cover" the clutches ive seen look like they already have cover basicly. ...... does this mean i can use a lower (higher torque) ratio on the 12hp and dtill have a good acceleration off the line and also have a higher top speed?

i just mean a chain cover in case stuff gets hot. I dunno. I doubt anything would happen besides the clutch shoes burning up. Who knows.

ABout the torque -- you're going to have the same basic power band, which is no torque until high RPM. However, the clutch engages at 2200 or so.

You could go for a higher top end...

I dunno, use the speed calculator on the home page and check how fast you want to go.

Another thought is that the generator might not have come with a high-speed carb. Meaning that it's made for slow increases in RPM, not fast. Got a pic?

[grandam88]

no i don't have a pic yet i have to pick up the frame an d motor on Saturday but i haven't thought about the carburetor but my guess is it'll be fine at least i hope so, lets say if you were me what sizes would you use im really new to this im just worried ill have a nasty take off speed as in ittl take me forever to get to top speed