150+ hp two seater rear axle chain driven

[Keef_it_Up]

I am building my first kart with plans of using a 160chp 900cc two stroke engine. (2005Arctic cat 900cc King Cat engine)
I am currently working out the rear end and have been trying to design my own solid rear axle. Not sure if anyone is a genius about twisting forces and such. Trying to make sure I build the axle strong enough the first time. What Guage steel rod do I need to handle the twist?

 

[FlyFrog]

as big as you can fit but wow 160 hp thats more than a lot of smaller cars impressive, the hyundai accent is only 120

 

[Keef_it_Up]

as big as you can fit but wow 160 hp thats more than a lot of smaller cars impressive, the hyundai accent is only 120

Which is why I'm scared of twisting the axle and locking it up.

 

[Denny]

I think you would need to use car parts for that.

 

[Pinhead]

I'd use something like a Subaru rear-end and if you want it to be "solid" I'd either make it a Lincoln Locker or install a LSD.

 

[madprofessor]

Can't figure why you'd want a solid straight axle for that kind of ponies. Regardless of what type axle, Denny's right about using car parts. The so-called "gokart" market doesn't even incorporate vehicles with that much power. There's other terms used for it like "buggies", "rails", etc., nothing really in the realm of "gokarts".
That said, check online for car performance parts such as rear ends with limited slip diffs. Get some info on what's rated for how much power. If in the end you decide you still must have a solid live axle, consider a rear diff with the spiders locked.

 

[Keef_it_Up]

Just to clarify, I am mainly trying to use a solid axle because I really want to avoid having to use a drive shafts instead of a chain/belt drive. I've been focusing my Internet searches on race quads and such because they seem to have the kind of power I'd like. I'm not sure how I'd be able to transfer power from a chain case to a drive shaft so it could go to a rear diff

 

[FlyFrog]

weld a sprocket to the input shaft of the rear end, you can use a suzuki samuri rear end or geo tracker

 

[Pinhead]

Just to clarify, I am mainly trying to use a solid axle because I really want to avoid having to use a drive shafts instead of a chain/belt drive. I've been focusing my Internet searches on race quads and such because they seem to have the kind of power I'd like. I'm not sure how I'd be able to transfer power from a chain case to a drive shaft so it could go to a rear diff

Take a look at Cracked Housing Fab's 4x4 Crosskart for inspiration. They essentially machined an adapter to bolt a sprocket to the input of a Subaru rear axle.

 

[Keef_it_Up]

Take a look at Cracked Housing Fab's 4x4 Crosskart for inspiration. They essentially machined an adapter to bolt a sprocket to the input of a Subaru rear axle.

I wonder if there would be any differences due to the fact that I plan on using a snowmachine engine, belt drive clutching and hopefully the original gearset to connect from the secondary belt to the axle, or in this case differential

 

[Keef_it_Up]

I wonder if there would be any differences due to the fact that I plan on using a snowmachine engine, belt drive clutching and hopefully the original gearset to connect from the secondary belt to the axle, or in this case differential

Also. Thank you very much for introducing me to my newest "show" as the wife call em

 

[Keef_it_Up]

19/43 ratio on the chain

 

[Willie1]

IMO you need to provide a lot more info before any kind of informed opinion can be made.
How you plan on using the kart, top speed, tire/wheel size/type, suspension type, engine location, engine RPM's, power management (clutch), and rear axle style, as in solid axle, differential, limited slip, chain drive or shaft, axle length/width - this is all info that needs to be considered before you can really expect to get an informed opinion on an axle selection. Also, some insight into your mechanical ability, budget and tools available would help.

Simplest solution would be using the belt drive to drive a chain, a jackshaft if necessary, and a solid axle. If you want a diff or a limited slip, that really complicates things at that power level.

Using a complete car axle to get a diff/limited slip function requires the power to change planes. That can get complicated and have packaging issue.

It would be typing practice for me to go through all the different scenarios and solutions that realistically need to be considered on a project like this. If you wanted to send me better contact info through the messenger here I would be happy to try to give you a better idea for a direction to follow.

In any case - good luck with your project. Willie

 

[Keef_it_Up]

IMO you need to provide a lot more info before any kind of informed opinion can be made.
How you plan on using the kart, top speed, tire/wheel size/type, suspension type, engine location, engine RPM's, power management (clutch), and rear axle style, as in solid axle, differential, limited slip, chain drive or shaft, axle length/width - this is all info that needs to be considered before you can really expect to get an informed opinion on an axle selection. Also, some insight into your mechanical ability, budget and tools available would help.

Simplest solution would be using the belt drive to drive a chain, a jackshaft if necessary, and a solid axle. If you want a diff or a limited slip, that really complicates things at that power level.

Using a complete car axle to get a diff/limited slip function requires the power to change planes. That can get complicated and have packaging issue.

It would be typing practice for me to go through all the different scenarios and solutions that realistically need to be considered on a project like this. If you wanted to send me better contact info through the messenger here I would be happy to try to give you a better idea for a direction to follow.

In any case - good luck with your project. Willie

Used on grave roads and some trails.
Top speed of 80-90kph
Atv tires - too be sourced
Independent front suspension
Rear suspension to be determined
Rear engine with 7200-7400rpm
Unkown clutching but should be good
Prefer solid axle to avoid cv axle breaks
Chain driven from the clutch
Approx 5.5ft wide wheel base. 7ft length
I am extremely capable but
I am extremely budget limited 50/month
I have a angle grinder, flux cored welder and a drillpress.
The changing of planes is what scared me away from using shaft driven car parts.
Also, plans are meant to change, it's a sign of progress being made.

 

[Keef_it_Up]

Take a look at Cracked Housing Fab's 4x4 Crosskart for inspiration. They essentially machined an adapter to bolt a sprocket to the input of a Subaru rear axle.

Perfect! I am now in search of a ford 9inch rear end haha. Will be perfect as they can handle as much as I'll ever throw at it and they have such a variety of gearings. If anyone could design a easier to manufacture chain unit like theirs that would be great because I know of few shops this far north that can machine something like that. I'd have to make it myself for sure.

 

[Willie1]

Something to consider in the 4x4 cross-kart above is that the clutch (and trans) is self-contained. Packaging a belt driven converter would be for the most part impossible in a front engine cart, and would not package well in the rear, either.
There would be a lot of engineering to make things "sorta" work.

 

[Keef_it_Up]

Something to consider in the 4x4 cross-kart above is that the clutch (and trans) is self-contained. Packaging a belt driven converter would be for the most part impossible in a front engine cart, and would not package well in the rear, either.
There would be a lot of engineering to make things "sorta" work.

All snowmobiles work on a continuously variable transmission (CVT) mechanism, with a pulley-based variant of the CVT system present in most models. The system consists of two clutches (or pulleys) connected by the drive belt. ... If your RPM is low, the two halves of the primary clutch are separated via pressure. after the power is transferred to the secondary clutch it goes through a jackshaft to an enclosed chain case. I think it could pack up nicely considering they fit in a snowmachine engine bay. Like 5 cubic feet. Easily manageable and protectable

 

[Willie1]

I fully understand how the CVT system works.

My reference was to the cross kart in the video's engine being mounted "sideways" in the chassis. A snowmobile mounts the engine with the crank sitting crossways in the chassis, and the CVT drive belt, etc. running parallel to the frame. This is "standard" for a kart that runs a chain drive. Since he runs axles that the flanges run parallel to the axles, he mounted his engine "sideways". His packaging is relatively compact, since it has a self contained clutch. OK. So, what happens when you mount your engine sideways - where does the CVT driven pulley go? Ends up being a pretty wide package with the drive sprocket way off center.
There's also engine rotation concerns - the axle rotation may dictate the driven pulley be towards the front of the machine.
And putting that much power to the ground with 70% of the weight on the rear tires will not help the kart turn - more likely it will be a poor steering wheelie machine.

Not trying to rain on anyones parade - just trying to point out possible obstacles to the different power systems.

 

[Pinhead]

If you want to keep the engine assembly (including CVT, etc) cross-ways you'll need a RAGB (Right-Angle Gearbox). For the type of horsepower you're talking about, you'll want an agricultural gearbox like this or similar: https://www.ever-power.net/product/rc-61-mower-gearbox/

 

[Pinhead]

On the other hand, since you're using a Snowmobile engine, you might as well take a look at what's already been done.

These guys put a 130hp snowmobile engine into a Honda Odyssey FL350. You could check out what they did for the driveline and how well it works.

https://www.youtube.com/playlist?list=PLL5hF_waT6s7fg8KwMlKgwMITyGZERfYo