New Kart with "two speed jack shaft"

[ErikDIY]

Alrigth people!

Here is my homemade Go Kart that i'm working on, I hope you guys like it, if you have any advice please tell

I've made this kart with a two speed jack shaft, witch will give me torque and speed. I calculated it to go 35 in low gear, and 58 in high gear.

I'll upload more pics as soon as i make any updates

 

[dave1701]

Good luck going 58.

 

[Badot]

Hopefully the intention is 58 kph, not mph. I have no idea what kind of engine it is, but I can't imagine it or the clutches would be happy with those figures in mph.

 

[B man]

its not that far fetched. i what if its un-governed? it could do it.

 

[ErikDIY]

Hi guys, well it goes 58 km/h, but it's fast enough for me. Especial because I'm going to use it off road. The Engine is a 5 hp briggs. The guverner is not removed, but i'm working on it.
I also plan to mill the head to get more compression.

It could go 58 mph, the low gear would just get it to speed, then the second gear would just keep pushing....

 

[JHen]

When you mill the head, just remember to put higher octane gas in it or you will ruin it in no time flat.

 

[karl]

Also when you mill the head, piston rings help. If they are worn (most are) when you mill the head, the extra compression will blow by the piston and be useless.

 

[redsox985]

I would add a floor and brakes first, but that's just me.

Now, I'm surprised it hasn't been asked yet... How do you engage the 2nd jack shaft? How does it all work? This looks really cool.

 

[r97]

i would guess the right most axle sprocket isn't a freewheel/one way bearing. then on the jack shaft is a cent clutch with tighter springs and/or lighter weights to delay engagement. when this clutch engages it spins a drum on bearings with a sprocket on it. this sprocket drives a sprocket on the axle faster than the first gear, so the freewheel disengages, and your in top gear!

i have wanted to make one of these for some time now, maybe now i will. what did you use for the free wheel? is my guess correct at all ?

@redsox, second jack shaft?

 

[ErikDIY]

OK... The first clutch engages, then it drives the low gear with a free wheel on the back sprocket, the same axle then has a second clutch, witch engages when the rpm is high enough. The other side of the axle has a clutch drum with baring holders. + second gear.

So, i give it full throttle the low gear engages, witch give me a god start, then the second clutch engages and the second gear takes over. when the second gear sets in the first gear just spin freely.

Well, the free wheel was something i got from my neighbor, I don't know what is used for, but a tip is to get a small sprocket with a free wheel, they can easier be purchased or make.
I had to use the lathe and do all the work myself, i used two days on it.
I'll post more pics later today.

 

[jrmints1415]

looks good but ur steering is not straight..

EDIT: Is it just me or does the js look crooked aswell?? I mean look at the chain, they are not straight!

 

[r97]

cool! tell us how well it works!

i kinda want to make a 3 or 4 speed version! LOL

 

[JHen]

That's a neat idea. I'll have to trying something like that in the future I think.

 

[ErikDIY]

*jrmints1415
Well, the steering was not finish at that time, i have fixed it now, so now it's lined up.

I have to tell you guys, the gears works great!!
I tried it today and i it goes like a beast!
The second gear had some problems, but some waigth on the second clutch fixed that.

This Kart is fun to drive, it has a lot of torque in the start so you almost spins when you give if full throttle. It's also fun to drive because of the speed. I drove it for a little trip up a hill, the only thing that happend was that as the speed slowed down, the fist gear set in it just continued to go.

The only thing left is a brake, witch hopefully comes in the mail tomorrow, I have bought a hydraulic brake caliper.

I also clean the engine, and found a unpleasant surprise, the block had a tiny crack in it, but i hope to get a new engine soon. hopefully 8 hp.

I also make updates all the time, so you migth see some changes

* New baring, and holders, the old ones broke

 

[mckutzy]

The second clutch, is this a homemade/custom device or is it a factory produced product? it looks very cool, and interesting use of parts.

 

[ErikDIY]

it's factory made, it came from a two stroke lawn mover, i have no idea of brand, but if you need a second clutch you can just make/ buy one, i would recommend to just modify a regular centrifugal clutch, but you needs to have a clutch house with baring holders.

* I did make the clutch house, it was made in the lathe, why i made it was because it needed to have baring holders.

The picture below is a drawing i made for the clutch house.

 

[ErikDIY]

Alright, here is an update

I've added a roll cage, why? Well, i don't like to roll and harm myself.

I've also added a new engine, the old engine had a crack in in + grease nipple on the steering

I'll add a gas and brake pedal soon, just waiting for the brake caliper.

 

[landuse]

Looking good. You have some good skills.

My only advice would be to make sure you put a seatbelt on there. You don't want to get crushed by that cage if you have an accident.

 

[ErikDIY]

Thanks landuse

I've had the same thought. I do think i have an old seat belt. I'll install it as soon as i can, just hope that it still work.