Building small tractor

[Pulse]

Ive found RPM gearbox, which is a F/N/R gearbox, Im thinking i will need multiple speeds to maximise the torque while still being able to travel at a reasonable speed empty

My highest gear would only need to do about ~20 mph, and the lowest would need to be around walking speed or so. If i use a cvt, the driven cvt with the engine @ 3600 rpm would be 4750 rpm, Im thinking I will need at least 15:1 ratio to get nearly what i need?

There is room in the machine for a little more gearing down, but not a whole lot. The tires will be 20" Carlisle super lugs

 

[Pulse]

Do some searches in on this site using the Google box in the upper right. There are some very talented people here that have built tractors better than a factory could.

I've searched to the end of the internet, been banging my head trying to find something that will work for ages...

 

[Pulse]

How about hydraulics like a skid steer. The biggest downfall is $. A more budget friendly solution would be an automotive manual transmission with gear reduction in front of it. Or you could use duel 4 speeds which doubles your gear reduction.

Hydraulics are still on the table as an option, Hydraulics arent as mannerly as a mechanical drive though. We have Kubota rtvs at work which are hydro static drive, guys hate them since they stop as soon as you release the throttle

 

[Pulse]

I thought by definition a CVT was a transmission?
I would look into finding a world class T-5 transmission, not too big or bulky. Or any older 4/5 speed transmission.
Belt drive the transmission then you can have a tensioner to act as a clutch for changing gears.

Cvt is somewhat of a transmission, only problem is you are limited to the variation of the cvt, Cvts do not allow you to reverse or multiply as much torque as a transmission. A 3 or 4 speed transmission with a cvt as a clutch may be the solution if i could find one. I do not wanna get into using old/scrap parts, I would like it to be all new and have the ability to replicate it.

 

[Pulse]

It used to be common to make your own tractor, or at least off road buggy, out of old cars. Back then two manual transmissions would be put in series, giving you tremendous gear reduction and fast speeds if you wanted it. You need to visit a good pick-your-own-parts junk yard to find reasonably priced parts.

Ideally I would like to have a sequential transmission setup like what you find on a honda foreman 500cc atv. those are about as durable as they get, i just cant find anything like it! Im also considering using a kubota 902d for and engine instead of the kohler.

 

[airbiscuit]

Im building a 8x8 articulating mini forwarder, the only ones you can purchase are in Europe and are very expensive, i believe i can build it far cheaper.

Might components salvaged from a forklift work? If you are building a forwarder, you will want robust components.

 

[airbiscuit]

Im building a 8x8 articulating mini forwarder, the only ones you can purchase are in Europe and are very expensive, i believe i can build it far cheaper.

So, you are looking to build something like this?

 

[D2Cat]

Hydraulics are still on the table as an option, Hydraulics arent as mannerly as a mechanical drive though. We have Kubota rtvs at work which are hydro static drive, guys hate them since they stop as soon as you release the throttle

I'm pretty sure there is a different valve you can put on your RTV to eliminate the sudden stop. Might check with your dealer.

 

[roadhunter]

That is a cool forwarder. I need one of those to go with my mini skidder

 

[airbiscuit]

That is a cool forwarder. I need one of those to go with my mini skidder
View attachment 496816

That is a cool mini skidder!