Gearing

[vetteman03]

Not sure what the gearing is on an 1997 electric CC. Ok Guys I need some expert advice on gearing. The tires are 23x10x14. The sprocket on my F-R-N transmission is 10 tooth for a 420 chain. Any idea what tooth sprocket I should look for to weld on the shaft where the electric motor used to be. It's a 3/4" 10 spline shaft. Not looking for alot of speed or for climbing hills. Just riding around in the pits and letting my grand kids putt around the neighborhood.
I can change the sprocket on the transmission if need be. Man if this were a perfect world or I had a machine shop I could make a sprocket that would fit a 3/4" 10 spline shaft.
I really appreciate all the help you guys have provided. While waiting on a belt & a couple more parts I have the throttle completed. Probably tackle the wiring today.

[vetteman03]

Update ! I found out the rear gear ratio is 12.5 to 1. So with that number I need to know what tooth sprocket to weld on the output shaft.
I thought I had found a 10 spline coupler for the 3/4" shaft, but it was for a 1 1/2" shaft.
I would rather weld the sprocket on a coupling so that I could change the gear ratio at a later date. Then I could slide the coupling off and replace it with another sprocket.

[slonomo]

What if you welded the coupler on the shaft, then bolted the gear to it? You could still change gears then. Never done it, but seems like a viable option? Might have to have a machine shop make a coupling for you? Might even have them make it to fit the gears. Lots of gears to choose from, just pick a style and go with it. Sometimes you don't know what gear to use until you try one.

Did you try searching the forum for "electric to gas conversion"?

[vetteman03]

Yea but not much luck on gearing suggestions. Probably start with something like a 12 - 14 tooth sprocket. I ordered a straight shaft coupling with a key way. It's for a 3/4 " shaft so may can make that work.

[sho305]

Stock cart is 13:1 trans, however in high gear the cvt overdrives .9 so top gear is about 11:1. But that is top gear, cvt will run about 3:1 in low gear to take off compared to .9:1 in top speed gear. So it depends on what speed you want, what clutch you are using, etc. With 22 tires and no governor that is about 30mph for a stock engine that runs maybe 4300 rpm floating the valves. Without a cvt or gears you will need something like 2:1 maybe, so to go 15mph top speed you would run twice the sprocket on the rear as the engine crank runs a sprocket. If you use a gokart clutch for example you cant gear too high it wont get going it will burn the clutch unless you are on a road.

[vetteman03]

I'm running a CVT. Also I have a F_N_R transmission. Just trying to get an idea of which tooth sprocket I should run on the rear. I guess you could say it is sort of like running a jack shaft. The transmission has a 10 tooth sprocket on the output/jackshaft. From that I will weld a sprocket on to a motor coupling that fits on the input shaft to the rear end. Take a look at some of my pics from previous post and you will see what I'm talking about.

[slonomo]

If you are running a chain between the crank and the cvt, then don't you want the same gear on each side so it's an even 1:1 transfer? That would be like a jackshaft setup.

I'm guessing you want more top end speed, so then on the crank use two or three teeth larger to start, build it so you can use a larger gear if more speed is desired. Or start with 14t on the front and 16t on the rear. Then you can swap them to get more speed, or keep a 12t on hand and throw that in the mix.

[vetteman03]

Originally Posted by slonomo

If you are running a chain between the crank and the cvt, then don't you want the same gear on each side so it's an even 1:1 transfer? That would be like a jackshaft setup.

I'm guessing you want more top end speed, so then on the crank use two or three teeth larger to start, build it so you can use a larger gear if more speed is desired. Or start with 14t on the front and 16t on the rear. Then you can swap them to get more speed, or keep a 12t on hand and throw that in the mix.

The chain is from the output shaft on the transmission to the input shaft where the electric motor was. I found a 3/4" hub at Tractor Supply today. I worked on the keyway to make it fit the 10 spline shaft where the electric motor was. It also has 2 set screws on the hub. I'm hoping it will hold up. One screw pushes against the key stock while the other luckily hits between the splines. The sprocket on the transmission is a 10 tooth and the only sprocket at TS was a 12 tooth. I'll weld it to the hub and see what that does. If the hub holds up I'll buy a couple more and weld different size sprockets to them. It will be fairly easy to change them out. Still have to finish up the exhaust and wiring. Thanks for all the help.

[slonomo]

Remember, larger gear on the trans will give a lower speed. To go faster, you'll want a smaller gear. Front gear you would go larger for more speed. On my quad, I would swap out the front gear for the most dramatic change in speed. Stock was 14t and I had a 12t for hill climbing and 11t for woods racing. I also had a 16t that I tried to set the "quad land speed record" (joking of course) , that didn't work out so good. Hopefully you are close speed/torque wise and adding a tooth here or there will get you where you want to be. It's hard to say with the cvt and differing gears.

[sho305]

If you have a 12:1 rear and you run 1:1 to the cvt you should have a cart that is slightly slower than a normal cart. So you would see around 28mph at 4300rpm or so. This assumes your trans is 1:1 in forward gear. 4300 is about top rpm for a stock lawn engine with no governor and no mods. If you gear lower (larger sprocket on the rear than on engine/cvt powered jack shaft) you will go slower but have more power, or the opposite if you go the other way.