New Gearing on my kart

[exenos]

I decided to take a break from working on my mini buggy and put my old kart back together with new gearing. Before it was geared to go 60'ish kph with my 6.5 clone. The gearing was something around 6:1. The new gearing I have is 14.4:1 and the difference is amazing. It only goes 22 kph now but the torque is completely worth it Spinning tires, ruts in the lawn, getting pushed back into the seat, awesome! . I have a old lawn tractor seat with a U-spring underneath it and the acceleration pushes the seat back, along with me

So, I guess what I'm really trying to say is if you have a jack shaft, spend the $15 and get a new hub and sprocket to gear it down to around 15-20 kph. If you don't do a lot of straight line driving this completely changes how you drive. Give it a try. If you don't like it you can always change it back.

 

[Nodroz]

I'd love to see a video of you driving that. I always prefered spinning tires, rather than going over 60KPH.

What are your sprocket sizes?

 

[Doc Sprocket]

Oh yeah! My kids' kart is currently geared at 12:1 and currently maxes at 21.5 Km/h (at 3600). My sons just cannot seem to get moving from a standstill without rooster tails. They love the feeling of power, but the speed is quite reasonable.

Now that they've gotten used to it, I will be regearing a little higher.

 

[aidantandy]

I'd love to see a picture of your setup exenos.

Can't find one in your other threads.

 

[Nodroz]

Can you really do spinouts with a gearing of 14:1, regardless what engine you have?
Oh and is this with a centrifugal clutch or TCV?

 

[exenos]

Nodroz, yes I was doing burnouts with this gearing. I cant do it on pavement because the tires hook up too well but on grass, dirt, sand, gravel or almost anything else it will spin the tires. And this is with a cent clutch that engages 2300rpm.

As for pictures, I'll try and grab some to-night after I put the custom exhaust on it (brother is insisting that i put a "stack" on it)

 

[Doc Sprocket]

Yep- I gotta back that up! My kids' kart weighs 200lbs empty and only has 4hp. With gearing that low, it chirps the tires all over the place. It's all about torque multiplication, baby!

Remember- Speed and torque are inversely proportional. When you divide one, you multiply the other by the same factor.

 

[exenos]

Well, I said that I'd have pics for you tonight so here they are. The first pic is of how it sat two days ago. It was cobbled together with parts we had lying around. The steering was also greatly improved. Before i changed it 1/8 of a turn of the wheel turned the wheels all the way left and right, now it's about 1/3 of a turn so we can actually use one hand to drive it now, before you needed both hands and your knees braced against the wheel to keep it in a straight line.

 

[landuse]

Cool kart

 

[Nodroz]

Yeah, a very nice gokart!
I'll keep this in mind when I'm designing my gokart. Thanks for posting the pictures.

 

[exenos]

No problem Nodroz. Thanks for the compliment landuse.

Just looked at the pics again and i am horrified at how terrible the welds are, I cant believe that they are holding up still. When this thing gets the sled engine treatment I will definitely go over all the welds again with the ARC.

 

[smallfry1227]

where do you get the bearing that bolt on the frame like that? and what are the name of them?

 

[OzFab]

where do you get the bearing that bolt on the frame like that? and what are the name of them?

They're a standard pillow block bearing

 

[spyder1968]

torque is FUN !

 

[aidantandy]

Yep - you've definitely inspired me Exenos.

Going to start crunching the numbers for jackshaft ratios. Not sure I want 14:1 but something up near 11 or 12 sounds good.

P.S is your Governor still intact?

 

[exenos]

Yep - you've definitely inspired me Exenos.

Going to start crunching the numbers for jackshaft ratios. Not sure I want 14:1 but something up near 11 or 12 sounds good.

P.S is your Governor still intact?

No the governor isn't intact, I took it out while I was rebuilding this because it was messed up anyways. So I'm hitting in the high 6K rpm's with this.