Why are there no street-legal 4-wheelers?

[JMcDonald]

I am surely just missing something, but it seems like a 4-wheeler adapted to the street (perhaps using even the same powertrains as their 2-wheeled cousins) would provide much of the fun factor of a motorcycle, but without many of the downsides. Being wider, they would be a little more visible from the front to other motorists, and they would also remove the obvious risk of laiyng the bike over. One could ride in rain, snow, or over leaves without any more concern for safety than a cage-driver has.

I can't think of anything preventing the prevalance of street-legal 4-wheelers. Why are there none?

[pushrod]

I'd guess that by the time they had a street-legal quad built, it'd be called a 'car.'

That, and who'd buy one? They sell very few three-wheelers now.

[seruzawa]

You can license ATVs for street use in Utah now.

[mscuddy]

In Arizona you can drive your ATV on the street with an off-road sticker. Go figure that one out.

[acecycleins]

DOT rules are why. It states that 4 wheel vehicles must have 5mph crash bumbers on both ends of the vehicle. Well, that's just plain silly looking so noone will sell a "street" atv. There are a few groups trying to change that with the boxer motored thingy and Hannigan selling a two wheel front end conversion for the Goldwing, but DOT isn't playing nice so that may take a while.
I believe that there would be a market for this product and believe that car tires mounted on these things would do the trick for stability. But those pesky bumbers are the sticky here.

[pplassm]

West VA, too. No sticker or plate needed.

In DC, people just do it anyway. Right down the highway, too.

Seriously, there are a bunch of reason why this is not done. 4 wheel "Car" safety standards are much tougher than motorcycle standards, and, as pointed out above, you'd end up with a real "Car". That's not even taking things like lack of a differential, sketchy suspension, and other factors into account.

[Kenneth_Moore]

I think Bombardier is on the same page as JMD with their Spyder. An open-air experience that won't fall over.

The new "Ultra" version of the Spyder is pretty damn neat. My HD pal is slathering for one. He's got a bum leg with a steel rod from hip to ankle. It's getting harder and harder for him to handle a regular bike. The Spyder seems like a good solution for him.

[JMcDonald]

So it is just for the random restriction that having four wheels automatically makes it a "car?" I know in some states / counties / cities they can be made legal with the simple addition of a headlight and such.

Two clarifications:
1) I am not talking about taking an offroad 4-wheeler and just driving it down the street. I am talking about essentially a 4-wheeled motorcycle, designed and purpose-built for the road. That is, tires, drivetrain, suspension designed for street use. I can't think of any reasons why they would be an inherently bad idea.

2) The purpose is not to try to effectively create an open-air car, but to create a 4-wheeled street bike. Or hell, even a street bike with two wheels in the front would be acceptable (but everything else the same from the clamp back, like seating position and controls; not one of those things that are basically like go-karts with a single back wheel). Yeah, it probably wouldn't be as manueverable as a racing bike, but then again most average bikes aren't either.

The point isn't to make something BETTER than a motorcycle, just to make something different (still, in many cases, actually safer--rain and even snow are no longer issues of safety beyond those of a comparable car).

And it's not like it would be an incapable machine (though I'd probably do without the bodywork between the wheels, even though I'm sure it helps aero).
YouTube - 2008 GG Quadster "Motorcycle" Review

[acecycleins]

J- The DOT won't let you get away with a purpose built four wheel machine without classifying under the passenger vehicle moniker. That's why the GG isn't actually selling bikes in the US. They can't seem to get the DOT to understand that the entire drivetrain is from a BMW R1200.
Basically, if you want 4 wheels and an open ****pit then buy a rail buggy. Your odds are better that it will get DOT approved.

[seruzawa]

Originally Posted by pplassm

West VA, too. No sticker or plate needed.

In DC, people just do it anyway. Right down the highway, too.

Seriously, there are a bunch of reason why this is not done. 4 wheel "Car" safety standards are much tougher than motorcycle standards, and, as pointed out above, you'd end up with a real "Car". That's not even taking things like lack of a differential, sketchy suspension, and other factors into account.

Utah has some restrictions like you have to stay way over on the right on a road with a speed limit of 45mph or more. But the main reason for ATV licensing is so that you can ride from offroad/private areas to town and get a burger or stop at the hardware store without running afoul of the law. The local LEOs in the town near where my cabin is in central Utah already allowed people to ride ATVs and dirt bikes on the roads as long as they kept it cool and stayed off the main drag. It's good for local business.