Hunter's Quadcycle
Okay, this is definitely one of my weirder ideas. Nevertheless, let's explore it. Dragging a deer or hog for any distance through the woods is an exhausting experience. The obvious solutions are an ATV or a horse. However, motorized vehicles are prohibited on most public land, and an ATV is expensive. A horse is also expensive, and must be cared for.
I started to think about traveling through the woods on a mountain bike while hunting. Bulky clothing and lots of gear make that impractical, plus how would I cart a deer home? That's when I thought of a pedal-powered ATV — a quadcycle. It turns out that there are quadcycles out there, but none that are designed for off-road use and hauling cargo. But what if I built one?
It should be a one-seater, but it should be possible for a passenger to ride in the cargo gondola. It should be lightweight. It should have a place to attach a rifle scabard. It should have a cargo gondola suitable for loading up a deer or a hog. It should have a wide range of gearing, so I can move up steep hills and tough terrain with a heavy load, yet still be able to make quick progress on roads. And if at all possible, it should have a power train that provides power to all four wheels. Oh, and it should have a more civilized seat than a bicycle.
I can weld it out of aluminum and paint it olive drab green.
Drive Train
I should be able to find the pedals and derailer from a regular mountain bike and use those. With the smaller wheels, that should provide a sufficiently low gear.
It should also be trivial to direct power to both rear wheels. In fact, there are probably drive systems for tricycles that do this. A differential should probably be avoided, since this is for off-road use.
How can I bring power to the front wheels?
Steering
I could do a steering wheel or I could do handle bars. An ATV uses handle bars. That is probably the best thing, especially since I can buy them.
Suspension
I probably should have a spring suspension system. A lightweight cycle doesn't need it, because the rider's legs perform that function. Here, we have a heavy cargo bed and the rider is in a normal sitting position.
Wheels
I don't want fat tires like on an ATV, because they are heavy. Mountain bikes can sink into mud, but not so badly that I need to worry. I don't need big 26" wheels, either. I'll bet common 20" dirt bike wheels would be fine.
How does the drive chain engage the wheels?
Cargo Gondola
There should be a cargo gondola large enough to hold a deer, a hog, or a person. My target capacity is 350 pounds (because the most likely person to ride in the cargo area weighs 300 pounds not counting his gear).
Whatever I come up with should be lightweight. Sheet aluminum, perhaps.
Brutus
Check out the tires on this Mongoose Brutus:
All-Wheel Drive
Drive wheels on bicycles tend to have a mechanism that is fully engaged with forward driving force, but is disengaged for coasting. I need to find out how this works. I think it would be ideal for all-wheel drive. The slowest wheel would get the driving force, and the faster wheels would effectively coast. I need to think about this more, or I may need to test it.
Comparisons
Lightfoot Cycles makes an ATC - All Terrain Cycle. At first glance, it seems like what I want. I like the recumbent design and the big seat. I wonder if that seat is a commonly available part. It sounds like it has only one drive wheel, but it has an articulating frame which gives it wheel travel to always keep the drive wheel firmly on the ground. It has 26" wheels and is available with fat 4" tires. They make a compelling case for both, and it looks good. It weighs 68 lbs. in its normal configuration and 78 lbs. with the fat tires. The cargo area is too small and I don't like that it has a single drive wheel.
Aluminum
6061 or 7005: Alumunum Frames: 6061 vs 7005: Which is the Best?