G-Rell's Go Kart Build

my concern is the alt not working below (lets say) 100 rpms... / needing to be at top speed to get anything out of it (even if i pulley it (the axle) as large as possible)...

I found this in case you didn't already: http://northwestkarts.com/files/CF150ServiceManual.pdf

The amount of vague specs on this thing are amazing. Some random mentions on google say it will go 27mph top speed. Assuming that is achieved with 22" diameter tires (seems to be a popular rear tire size on buggies), that gives you around 400-RPM rear axle speed at the top end.

So in order to drive an alternator, you would need somewhere around a 10:1 pulley ratio for the alternator to be useful at anything other then full speed. Assuming you have a 1" alternator pulley (which is already pretty damn small), you'd need a 10" pulley on the drive shaft for it to spin fast enough. At 1" you'd have to use a ribbed belt not a v-belt too. V-belts don't like small diameters.

It would be better if you could drive it from the output shaft/pulley/variator (whatever it has) but that looks like it's sealed with a cover. That just leaves trying to drive it from the stator fan and I doubt that's strong enough to support the tension of a belt/pulley. Pop the fan shroud off the thing and see. It very well might be beefy enough to support 2-HP or so considering the magneto spins from it. If that's the case then it's just a matter of rigging a pulley to it.

To make things easier use a mini-alternator. They range from 35-50 amps and are 1 or 3-wire setups. Here's a pretty cheap one: http://www.amazon.com/DB-Electrical-AND0525-Alternator-Chevrolet/dp/B00KGIDF9Y

Less weight means less power drag to spin it, and 35-amps is more then enough to power your lights.
After watching a few teardown videos the shaft for the stator is certainly big enough. You might be able to take some steel bar or tube stock tap it to be the same size as the nut that goes on the flywheel. Could also weld some tube stock to the stock nut. Either way you'd extend the shaft up about 2" for the pulley. You'd have to cut a hole in the middle of the stator fan and fan cover so that the shaft can clear it, but that would definitely work.

Another way would be to use a flange with the same bolt pattern as the fan, and have a shaft welded to the flange that sticks out for the pulley. You'd basically then through bolt the fan and pulley onto the stator housing. So it would be Stator --> Flange --> Fan. Nice thing about doing that is if you turned the flange out of a single piece of billet or 1/4" stock then you could use the center hub of the stator as a centering ring and the 4 bolts just hold it together with the fan.

IF you knew someone who was a fabricator you could also just have a new fan made out of metal and integrate the pulley into that too. :p

**** like this makes me miss working in a machine shop :(
Yep have the OM printed and i a book already

Rears are 20x10x10's

no fab work around here... but I'll def. take the cover off and see what can be rigged without placing too much stress on that shaft.

a 10:1 is possible...

but what about a double pulley system... Torgue (i think) would be way down, but only need to spin the pulley... so axle shaft (lets say 7"OD) to an aux shaft with with 1"OD that shaft has another 7" pulley on it belted to the alt... does that double my belt speed at alt making it 14:1? (or do they cancel out)?
I dont know any GOOD fabricators either....

Anyway...so whose go-kart is this really? I bet I know who will be doing the most driving. Poor kid...
I dont know any GOOD fabricators either....

Anyway...so whose go-kart is this really? I bet I know who will be doing the most driving. Poor kid...

Ha.. the only JEDI fab guy I know wont return phone calls!!!!

I know, I know... i need to relax on it a bit!... Just found a guy who did an independent rear on it.... very cool

Is this electric start engine? If so, is it 120V outlet? I presume you'd already have a solution if there was a battery on board.
Yes its electric start...im guessing 120vac for the whole engine. and a portion goes to the rectifier (IIRC) and that 12V goes to the battery to keep charged... This 12v is low amped and watted though, and not enough to power anything extra. (something like 75w or 6amps total)
I didn't know if it needed a wall outlet is what I meant, like a snow blower. Mine is simple pull start engines so I wasn't familiar with how yours was set up. Is it a tractor/motorcycle battery?

I see performance ignition kits with stators and coils, but no idea what they put out at idle. Seems like they're mostly for better spark at higher RPM? Might be worth a try since you wanted to upgrade it anyway. It might have enough to power what you want.

Got ya... ya my snow blower does the same... motorcycle battery..

agreed. we reviewed the 11 pole stator earlier in this thread, not sure it has the punch we're looking for. Once we get the voltage problem solved we'll look at hp. They make a hotter CDI kit that should help too... honestly though there's only so much you can do with a 150 (for a reasonable price) ... we'll look at upgrading to a larger displacement if this hobby sticks.

the preditor line is becoming quite popular from what i'm reading... because of its price to hp ratio... but questionable in quality (600cc 22hp for $700)
Kart back.. Runs like a champ (for 150cc)!!!

Going to move forward with the alt idea. (separate charging from stator system for aux stuff) .

From my sound guys.. Whats the best battery for this: (random car battery vs specialty battery)

Lots of up and down charging
size and weight a slight concern
nothing TOO expensive

I suspect that it needs to be shock and vibration resistant as well. All in all, I think that "nothing TOO expensive" is at odds with the other requirements. Maybe start cheap and see if that is good enough.
I would think that you wouldn't need anything too special for the gokart, a small(er) mower battery or powersports battery (like for a RZR/side by side) they would be small enough, and those see some pretty harsh rides...

if you really want to save on weight, you could even go with a super light L-ion battery.

wasn't too long ago I worked on a guys BRZ and I guess the hot new craze is everybody is using lawn mower batterys to help with handling and weight savings. he was using a lithium ion motorcycle battery, was probably about 6"x6"x3" and weighed next to nothing. he said he pair around $160. long story short, I figured the battery might be a little small to run the car and a 1000W 5ch amp, but he says that it has been doing very well.
reverse kit
and a few extras ordered

Once we get the alt installed (make sure we can). I'll get an AGM battery ordered

Baseball all this weekend

But on 5/28 a trip to the Hite Performance Shop.... to weld in a hood and dash!

Then strip and paint
Hite Performance Products
Hite GoKart Customs
Hite kinda-OK Fabricators, Inc.

Just how many business' does this guy have?
Technically....only 1 but who's really counting. Its called Hite Does Almost Mostly Everything Sometimes...H-DAMES for short.


and the G-Hite bar&grill
Is the official slogan: "Have machine shop, will whore skills out for money!" :p

I'm just jealous. I miss working in a machine shop. Nothing like getting something that doesn't fit, disappearing in the back with it for 30-minutes, and going "Yup, it fits now!"

HA... your welcome anytime my friend (just drive up)..

not sure on a slogan, It'd probably be: "that should work" or "what if we"

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