For street legal motorcycles, generally yes, but state laws vary when adding another wheel. With vehicles like the Polaris Slingshot, which was initially considered a three wheeled motorcycle in some states, those laws are being, and have changed in places. I suspect if that oddity became more popular, more states would draw a dividing line between two and three wheeled vehicles, likely with some exceptions for motorcycle based trikes and sidecars. Then there are those Can Am things, and other three wheeled vehicles like Morgans. Plenty of tri-wheeled conveyance options for someone with four wheel anxiety.
I own a platypus of the two wheeled world, a moped, which is designed so that it purposefully isn't a motor vehicle, therefore licensing and registration is minimal or nonexistent for road use. Instead, it is legally considered a motor-driven cycle in some places and not a motorcycle. Although, many of them can easily be built to reach and maintain highway speeds, but that also legally puts them into the motor vehicle classification and would require the proper licensing and registration.
I don't really care how someone goes about getting anything legal. If their state DMV passes it through, then it's legal enough. What I'm interested in is digging stuff up for the informational value. Some of this stuff isn't easy to find and state vehicle laws vary like state alcohol laws. Those ABC stores in Virginia seemed strange, and Utah, those crazy Mormons got other ideas too. Many parts of Arkansas are still dry, and several that aren't, don't allow sales on Sunday. BYOB for anyone vacationing in Arkansas, just in case.
Please elaborate.
There are plenty of go-karts out there with one-wheel drive (and brake). A different application, for sure, but many of them are pretty fast and used on pavement.
I just grabbed this from a go-kart site:
Differentials
A more complicated solution to this problem is to use a differential on the rear axle, just like a car has. This allows both wheels to be powered, and allows for easy cornering. However, it's not the best solution for serious off roading. This is because when traction is lost on one wheel, it will spin and the other won't turn at all, effectively giving you a single-wheel drive. These systems are readily available for less than $100.
Single Wheel Drive (Fixed Axle)
If you plan to use the kart for serious off roading, then a live axle is the way to go. But for hard-pack and asphalt, you can't beat a single wheel drive for the price.
A single wheel drive runs a chain from the engine clutch straight to the drive wheel, which has a sprocket mounted directly to it. The other rear wheel is left to spin free-wheel.
A single wheel drive is by far the easier and cheaper than a differential, and give you the needed slip for on-road and hard pack dirt driving.
https://www.diygokarts.com/kart-part...rive-axle.html
Of course, it'll be about useless on anything but pavement and hard-pack, and there wouldn't be an option to switch during a ride, without some custom locking hub. I haven't done it, but I've thought about it quite a bit, even trying one way bearings, to either have two drive tires, or two braking tires if that was a workable compromise. I don't think the one way bearings would function like intended during a turn though. I could guess at it all day, but until trying it, I wouldn't know for certain. Best I can tell, nobody has tried it. I done it to my mini trike, but that has a top speed of about 25mph and is scary enough, mainly because of the crazy steering angle, but also because the mass of the rider is behind the rear axle.
Of course, trying to do wheelies could be very complicated.
I don't know what this guy has going on, but something is fishy with that rear axle. https://www.youtube.com/watch?v=vLdzmWcKjJ0