Using A Jackshaft For Cheaper Twin Engine Gokart

[CillerCrocCustoms]

Hello everyone , I am looking to build a twin engine gokart which would use two Predator 212s. I know that you guys at DIY Gokarts are very knowledgeable when it came to prior posts I’ve had. And so I come to you once again for this question…

If I run the first 212 to the wheel through a torque converter to a sprocket wheel. Than I hook the second 212 to an opposite side sprocket wheel through a torque converter with a jackshaft added to the driven pulley and a sprocket going down to the sprocket wheel. Would this work? Would it overrun the the first 212? Anything you know is appreciated, thank you!!

 

[Denny]

No, it will not overrun the first one. But the first one will drag the other one down. Now if you could figure out how to install an overrunning clutch (sprag clutch) in the first engines secondary clutch then it would work. But you’d never find one small enough or strong enough to work. It also has to be able to take the shock loads. Oh, one other thing when they blow up and they will blow up it better be covered by a ballistic grade blanket or shield! It’d be like being shot with a 12 gauge shotgun!

 

[bob58o]

I’m confused.

Are you just trying to run a twin engine kart?
Or are you trying to do something like a 2-speed automatic transmission using two continuously variable transmissions?

 

[Denny]

I’m under the impression he’s wanting a 2 speed transmission.

 

[CillerCrocCustoms]

No, it will not overrun the first one. But the first one will drag the other one down. Now if you could figure out how to install an overrunning clutch (sprag clutch) in the first engines secondary clutch then it would work. But you’d never find one small enough or strong enough to work. It also has to be able to take the shock loads. Oh, one other thing when they blow up and they will blow up it better be covered by a ballistic grade blanket or shield! It’d be like being shot with a 12 gauge shotgun!

If I were to run the setup with the other getting run down, would it be damaging? This is my first twin engine kart build, so I am very new to this!

 

[CillerCrocCustoms]

I’m confused.

Are you just trying to run a twin engine kart?
Or are you trying to do something like a 2-speed automatic transmission using two continuously variable transmissions?

I would like to just run

I’m confused.

Are you just trying to run a twin engine kart?
Or are you trying to do something like a 2-speed automatic transmission using two continuously variable transmissions?

I am trying to run a twin engine kart. Two Predator 212s, each with their own torque converters

 

[CillerCrocCustoms]

I’m under the impression he’s wanting a 2 speed transmission.

No I just want to have the output of two Predator 212s to go the sprocket wheels I have

 

[BrownStainRacing]

Only 2 ???

Why not use 4 ??

 

[CillerCrocCustoms]

I could only imagine!!

 

[ezcome-ezgo]

No I just want to have the output of two Predator 212s to go the sprocket wheels I have

Then what is the purpose of the jackshaft on one, but not the other? Set them up identically.

 

[CillerCrocCustoms]

I had some time away to think it over, and I think I know how I could do it. Have both engines running to a long jackshaft and run the jackshaft to the wheels. Fingers crossed. Thank you so much!

 

[Thepartsguy]

Two predators cost $200 at best $200+ if your not getting each of them for $99 out the door.

Two $30 torque converters pushes you up to $260 and not accounting your shipping costs.

jackshaft is gonna cost so lets just push that total to $300+ Because why not?

We’re not gonna count that spool of welding wire you bought of course to keep cost down. Another good way to keep cost down is to not count grinding disks/paint into the final cost either.

When I built mine I kept it as simple and as LOW COST as possible.

Edit:
Two sprockets
Two chains
Two throttle cables
Two kill switches
EXSPENSIVE
Two engine mounts

Ever want more power?
Two stage whatever kits instead of one.

 

[hardcorps]

Lose the live axle and drive each rear wheel separately. Or, just cut it in the middle and use two more axle bearing hangers in the middle.
Add a brake rotor to each half.

 

[Thepartsguy]

Lose the live axle and drive each rear wheel separately. Or, just cut it in the middle and use two more axle bearing hangers in the middle.
Add a brake rotor to each half.

I would not waste my time going open wheel at all..

 

[hardcorps]

Twin 212s are cheaper than a 420, but are they better?
Has anyone done a twin engine AWD kart?
Interested to know how this will perform with two motors on one solid axle.

 

[ezcome-ezgo]

A 420 will weigh less than 2 212's, so no, not better. Twin engines are cool though, as long as they are synchronized.

 

[OffRoadGoKart2024]

My experience is in trucks from minis to semis. plus, OPE.

Though it is uncommon, it is not rare, to have two big 120 cc chainsaws running a bar, attached at each end, for slabbing, running on the same chain. I am pretty sure how this works is you do not get double the HP or double the TQ. What you do get is steady power and you do not bog down while clearing the chips/sawdust, while avoiding clutch slippage. It is possible to have a chainsaw with enough HP and torque not to stall out in the kerf/cut, the problem is the clutch can only be so big and is limited by many things. Having two power heads divides the load on the available surface area of the clutch. A higher chain speed equals a smoother cut and quicker cutting, especially when using 0 degree cut chain.

Since I usually work by myself and do not have a mechanical or human loader, I stick to smaller slabs, small bars, and one engine (Stihl 660) to uncomplicate my life. So, I sold my Husvarna 3120 (120 cc).

Unless you put each engine on it's own axle or wheel, you will be unlikely to see any improvement in performance off the line, unless your cart is pushing 2000# or something. Where you will likely find performance is going up a steep incline or when buried to the hubs in mud. If using two engines, then I would look at one for the front, one for the back for weight distribution. Maybe locate the front one in a double seat cart between the legs.

As someone mentioned, I would certainly be aware of engines and clutch parts coming apart.