John Deere ATV

[Adrenaline]

Hey folks. I've been working on a concept for a few years now to turn my 28+year old john deere lawn tractor into an off-road machine. The concept(pipe dreamut is to keep up with the atvs at the local dunes. Now if I fall short of that goal I don't care, its the atvs who are defending their superiority. Now I have a question for those experienced with transaxles. Suspension is a must out there and while the frontend is simple the rear had me stumped. Finally i thought of independent swingarms off each output shaft. If I support the original outputs with a pillow block against the trans case and another on the end of the shaft will it have enough support to take the abuse(outputs are only 3/4 inch diameter)? I have 5 inches on both outputs to work with. Can I fit the 3-4 bearings I'm thinking will be necessary onto each shaft plus a sprocket to transfer power to a 'stub' axle on the other end of the swing arm?

 

[Fat Boy]

Hey folks. I've been working on a concept for a few years now to turn my 28+year old john deere lawn tractor into an off-road machine. The concept(pipe dreamut is to keep up with the atvs at the local dunes. Now if I fall short of that goal I don't care, its the atvs who are defending their superiority. Now I have a question for those experienced with transaxles. Suspension is a must out there and while the frontend is simple the rear had me stumped. Finally i thought of independent swingarms off each output shaft. If I support the original outputs with a pillow block against the trans case and another on the end of the shaft will it have enough support to take the abuse(outputs are only 3/4 inch diameter)? I have 5 inches on both outputs to work with. Can I fit the 3-4 bearings I'm thinking will be necessary onto each shaft plus a sprocket to transfer power to a 'stub' axle on the other end of the swing arm?

Sounds like a great project and will be a lot of fun:thumbsup:

 

[WLB]

Google "Lawn mower racing" or "Racing lawn mowers" and you will find forums and businesses that will be able to help you. I don't have the name of the business but at the Indianapolis Motorsports Industry trade show earlier this month there was a booth with all sorts of items for lawn mower racing. They had one that was built on a stock chassis that lowered the driver almost as low as a go kart. Had a radical twin cylinder Kohler in it.

 

[The Restore Kid]

The biggest thing I see wrong is, well, handling and jumping and stuff WILL get you killed going 40 on a mower in the sand.. :doah:

But, the transaxle will most likely NEVER hold up to the abuse.. You'd be best to just jam some kind of racer rear end in it.. And possi for sure, one wheel apeal is worthless in sand..

 

[Adrenaline]

The biggest thing I see wrong is, well, handling and jumping and stuff WILL get you killed going 40 on a mower in the sand.. :doah:

But, the transaxle will most likely NEVER hold up to the abuse.. You'd be best to just jam some kind of racer rear end in it.. And possi for sure, one wheel apeal is worthless in sand..

I was asking from a structure stand point if i support each end of the outputs with a pillow block can the 3/4 shaft take the abuse of another pillow block in between acting as a pivot for a swing arm. the swing arm idea has the added(theoretical) benefit of allowing an overdrive after the tranny so it doesnt have to be spun as fast(stock or near stock pulleys). So I know the trannys don't like shifting on the fly if that is what you mean about not holding up to the abuse.I was also considering a one way needle bearing (freewheel) in the sprocket drives so I could rig the trans to stop when I shift(I was told the spinning output shafts were the killer of mower axles when shifting on the fly). I was planning on welding the differential. As far as handling if i can pull off the rear suspension, A-arms up front would be easy, and i was planning on 4 wheel disc brakes. For safety as much as I didn't want to I've admitted to myself it would need a roll bar and seat belts. So much for the "hold on tight" factor if i put a passenger seat on, but I'd rather not die.
So have I considered everything or is it still just a pipe dream?

 

[incogrhino]

Id just get a cheap odyssey ...put a fat snowmobile engine on er......and spank em. Well actually ....thats what im building during/after this build off is done.

 

[cumminsbayou]

you know john deer made a 4 wheeler a while back called the john deer buck can am made it for them and they didn't have them long

 

[Adrenaline]

Id just get a cheap odyssey ...put a fat snowmobile engine on er......and spank em. Well actually ....thats what im building during/after this build off is done.

Sorry but I've seen it done before. Also I want to keep it Made in America. All the quads are built by gooks and it just seems like a good way to get revenge if I can pull it off. And if I fail I still have a cool conversation piece and boohoo my tractor is still slower than a quad:1orglaugh:. If I can even hit 30 through the dunes I'm still winning. I Guess it's time to buy some metal and take on the impossible.:grind:

 

[oldsledz]

I think Polaris, arctic Cat and Canam have quads made in the US or Canada.

 

[cumminsbayou]

yeah polaris does and arctic cat is to and can am is in canada

 

[The Restore Kid]

I was asking from a structure stand point if i support each end of the outputs with a pillow block can the 3/4 shaft take the abuse of another pillow block in between acting as a pivot for a swing arm. the swing arm idea has the added(theoretical) benefit of allowing an overdrive after the tranny so it doesnt have to be spun as fast(stock or near stock pulleys). So I know the trannys don't like shifting on the fly if that is what you mean about not holding up to the abuse.I was also considering a one way needle bearing (freewheel) in the sprocket drives so I could rig the trans to stop when I shift(I was told the spinning output shafts were the killer of mower axles when shifting on the fly). I was planning on welding the differential. As far as handling if i can pull off the rear suspension, A-arms up front would be easy, and i was planning on 4 wheel disc brakes. For safety as much as I didn't want to I've admitted to myself it would need a roll bar and seat belts. So much for the "hold on tight" factor if i put a passenger seat on, but I'd rather not die.
So have I considered everything or is it still just a pipe dream?

Yeah, overspinning them is bad on them too..

But I mean the gear box itself.. You are putting such a (load) on it, that it literally just blows apart like it was made of glass..

LOTS OF THEM do it.. Just riding around the yard mowing the yard, dump the clutch one day, and that was all that she wrote.. :mellow:

That is usually the thin aluminum transaxles though.. If you have an (old) John Deere, with the huge cast iron rear end, and set up to be horizontally driven, you will have a far far far stronger gear box..

BUT it will weigh about 11 million pounds too.. :doah:

 

[ric03014]

I always get a kick out of the custom machines I seen cruising the dunes. A John Deere tractor would be a first for me, and I've spent a fair amount of times at the dunes. I'd love to see a John Deere that could go up some of my favorite sand dune hill climbs. Sounds like a very expensive project to me.

 

[Adrenaline]

I always get a kick out of the custom machines I seen cruising the dunes. A John Deere tractor would be a first for me, and I've spent a fair amount of times at the dunes. I'd love to see a John Deere that could go up some of my favorite sand dune hill climbs. Sounds like a very expensive project to me.

The chassis work I'm considering would be maybe 5 or 6 hundred with good shocks. What Id like to do to the engine is a different story entirely. Briggs and Stratton 399cc flathead, and if the rest of the project comes to fruition I wanna take a page from the 50's and build/have built an ohv head. No idea what the CNC work would cost on that.

TRK thanks for the input. I'll continue researching on ways to make the tranny last or a good alternative. I had been hoping running a chain drive and stub axles I could add enough breaking points to the drivetrain to prevent damage to the axle.

 

[The Restore Kid]

Yeah I think you'd be best off with the chain driven rear end, from a tranny.. The little Peerless 3 speeds are pretty tough (for what they are) then you could build a box around it.. Like a block girdle, to keep it from being able to expand and crack.. I know the racing guys replace all the bushings with bearings in them.. :shrug:

I would just buy a Honda 350X three wheeler thats been rolled and beat and needs about everything..

Then just pull that engine and tranny.. New rings, seat the valves, new clutch..

WOW!!! what a bunch of horse power, light weight, built in heavy duty 6 speed standard.. :shrug:

 

[Adrenaline]

A peerless 3 speed would work for what I wanna build. It wasn't the way I wanted to go but better than using Atv parts for the cool factor.

 

[The Restore Kid]

That may be your best bet.. Then you will be driving it vertically.. and they DO sell LOTS of build em up parts for the old 12 horse flathead briggs vert motors.. And those things are bad ass motors for the size and weight..

 

[paul_probus]

I was asking from a structure stand point if i support each end of the outputs with a pillow block can the 3/4 shaft take the abuse of another pillow block in between acting as a pivot for a swing arm. the swing arm idea has the added(theoretical) benefit of allowing an overdrive after the tranny so it doesnt have to be spun as fast(stock or near stock pulleys). So I know the trannys don't like shifting on the fly if that is what you mean about not holding up to the abuse.I was also considering a one way needle bearing (freewheel) in the sprocket drives so I could rig the trans to stop when I shift(I was told the spinning output shafts were the killer of mower axles when shifting on the fly). I was planning on welding the differential. As far as handling if i can pull off the rear suspension, A-arms up front would be easy, and i was planning on 4 wheel disc brakes. For safety as much as I didn't want to I've admitted to myself it would need a roll bar and seat belts. So much for the "hold on tight" factor if i put a passenger seat on, but I'd rather not die.
So have I considered everything or is it still just a pipe dream?

I really don't see how your idea of a swing arm is going to work. I would recommend cutting the axle shafts as close to the tranny as possible and using universal joints so that the outboard axle shafts can pivot with the swing arms, while the tranny stays bolted tight to the frame. The complication is that you will need a way to take up the change in length needed for the independent suspension in the axle shafts, on cars this is done with splined shafts, one male, one female, as the suspension goes up and down the axle shaft "lengthens" and "shortens" at the spline. For a homebuilt item, I think using a square or hex male and female would work well in place of a spline shaft, just grease them up.

This is kind of what I am talking about, although the outboard axle shafts and lower swing arm pivot at the same distance negating the need to take up the lengthening and shortening of the axle. Or that may be taken up at the hubs or at the differential.

Image Detail for - Independent Rear Suspension Photo 9


Here's a photo of an actual ATV independent rear suspension. Note that ATV's typically use CV joints, which are an alternative to universal joints. I know when I researched them back in college (early '90's) for the SAE Mini-Baja competition, CV joints were super expensive by comparison, you could get universal joints from McMaster Carr that were much cheaper and pretty heavy duty for much less. Things may have changed or you could scrounge some from a junk yard ... er... I guess the more PC description, now, is used parts dealer. :laugh:

Image Detail for - ... independent rear suspension, a sturdy hitch, and excellent ground

Paul

 

[5horsebriggs]

That may be your best bet.. Then you will be driving it vertically.. and they DO sell LOTS of build em up parts for the old 12 horse flathead briggs vert motors.. And those things are bad ass motors for the size and weight..

I hwve an old 12 horse on my murry mower, they are great mine needs a new fly wheel tho

 

[Adrenaline]

That may be your best bet.. Then you will be driving it vertically.. and they DO sell LOTS of build em up parts for the old 12 horse flathead briggs vert motors.. And those things are bad ass motors for the size and weight..

Mines an 11hp. Will the hop up parts still fit? I was assuming Id have to have common parts(rod and flywheel) reworked to fit. I'm with you on the level of badass these engines are capable of.

 

[Adrenaline]

I really don't see how your idea of a swing arm is going to work.

The swing arm idea is quite simple in theory. Each axle shaft would be equipped with a sprocket locked into place on the keyed shaft. Then a pillow block would go against the sprocket and the swing arm would be attached to that. The original axle shafts would effectively become jackshafts. A stub axle would be in place on the trailing end of the swing arm and a chain drive would transfer the power from the trans. Since the swing arm would pivot on the axle shaft the center to center for the sprockets wouldn't change so the chain wouldn't go slack as the suspension cycles. The suspension you linked to was A arm suspension(pivots on the longitudinal axis of the vehicle).

Quadparts.com.au - Perths Newest ATV Store

This is what I was considering but with each wheel having an independent swing arm rather than be linked with a full width axle. But I'm not gonna go for that, Unless I find a way to beef up the tranny to avoid the problems TRK brought up. I'd always been told the internals are rather bulletproof and the case was the biggest issue.