homebuilt ATV

[daveshoe]

I just bought a homebuilt something -or -other that has a 17HP twin briggs, a 4 speed step transmission and a front end that has no gear reduction--that is one quarter turn is rack-to rack on the steering. The present front wheels are 6 inch to make it possible to steer I am thinking that a small hand winch can be used to multiply the turns of the wheel for steering. Steering u-joints might be as simple as u-joints from a 3/4 drive socket set. Hopefully this would enable me to add larger front wheels

I want to make a low-speed ATV with max speed of ten-to 15 MPH. Part of this will be accomplished with bigger tires and part with final drive pulley on the belt drive. Prresent suspension is solid front and rear with no springs. The suspension that I have considered is 1. No changes--just add big tires with low air pressure. 2. add pivot to front so the front wheels can twist when dropping into a hole[garden tractor suspension like a wheel horse]3. Also add a suspension seat with springs and shock that floats over the sub- frame.

I feel that this is about my level of understanding and skill. I am enough of a realist that adding a really complex independent suspension would eat enough of my time that a second job at a low wage would be cheaper that trying to build a coimplicated suspension system. This machine 's purpose is to get back in 3 miles or so in the South Dakota gumbo that adds 5 pounds of mud on your shoes if you try to walk in after a rain. I need to keep the frame higher than a go-kart so the transmission will not get muddied up.

If you can stop laughing at these ideas long enough to offer advice ,let me know your thoughts

 

[thejeepdude]

i think without pics it's going to be hard for anyone to accurate present any suggestions... just a suggestion sounds like an interesting beast, though... a lawnmower derivitive?

 

[daveshoe]

Yep, it's lawnmower parts,. It has 12x22 atv tires on the back with 6'' tires on front. It looks like a drag racer with the engine right in front of the seat. This causes problems with the operator being too cramped. I need to move the engine forward to get legroom, but then the steering column will need to be U-jointed because the present arrangement has the steering column right over the top of the engine. The front end would also benefit from additional weight. I agree about the picture,but I have no digital camera.

I need to move the back tires to the front and get bigger ones for the back. It looks like a five bolt Wheel horse wheel assy might work for the rear. I hope to adapt the 12x22 wheels for the front with a split hub wheel to keep it simple.

I looked on the internet for some plans,but most are for kart type assemblies and do not show how to fabricate suspension parts. I realize that the existing transmission and front end are not made for going airborne ,and my goal is to produce a high flotation unit that will go in the mud.

 

[nickleinonen]

for the steering shaft u-joints, a 3/4" impact swivel joint would work well. if they can hold up to close to 1,000ft/lbs of hammering with an impact, it will work good...



i just used the snapon one in the link for ease of linking, but proto, armstrong, gray, westward all make similar pieces at less cost. .

 

[RAMINSPEED]

Sounds like a riding mower. Heck, I'd go down to Sears and pick one up and remove the deck. I have 20 hp mower and I don't think the 17 hp is enough in gumbo. I might put 2 of them in one machine.

 

[daveshoe]

I found a nice used heavy mower chassis that is perfect for the steering. A mower shop bought a used tractor for a cheap repower for a blown Dixon ZTR. It looks like the chassis wheels will work for an ATV tire. There are also some homebuilt off-road kart sites that have some good info. I will experiment with the parts I have before going to the time and trouble of fabricating the whole thing. Worst case scenario is abandon the project and repower a Dixon lawnmower with the engine.