I'm not sure why I found this so fascinating, but I read this guys entire page. He runs a car tire on the back of his Valkyrie. While I'm sure there are some advantages, he swears it corners better than it did with motorcycle tires, which I find very hard to believe.

http://lifeisaroad.com/stories/2004/10/27/theDarkSide.html

Also, a related video:

http://www.youtube.com/watch?v=Ay3ZVmORDl4

Hahaha. Crackpots win.

"I swear it's better, man. I can't believe no one thought of this. Those MotoGP dudes are just dumb."

Ya know, if all ya do is go straight he may just have a point...wonder how many miles that side wall last?

Always amazing when an average Joe thinks they have an end round to millions of dollars, teams of engineers, degreed market annalists and years of experience...not saying it never happens but I’d say the lotto would be a safer bet...and that ain’t sayin’ much. Possible member of the MMTB club?

EDIT> Actually, at the very least I'd say it works for him...it's all about context...
I'll spank you with my GX'er
Okay, I get this one a lot. Not to put too fine a point on it, but aside from the rather bizarre sexual implications of that statement, you most certianly won't....at least not if I get to choose the course. Please note, the Valkyrie is a Heavy Cruiser, or what might be called a Power Cruiser. Loaded, it weights over half a ton. Nothing I can do to this machine will make it outhandle a gummy-tired, 400-pound crotch-rocket in the corners. When I'm throwing sparks off the hard-parts and hanging off the side of the bike, that is the maximum cornering I can get, regardless of tire. What this means is that the Valkyrie is not made to spank your GX'er in the short term. It's made to cruise. That's what I bought it for, that's what I use it for. It corners remarkably well among the heavy cruisers, but it's still a heavy cruiser. Oh, my choice of course? Well, it has lot's of nice cornering roads...but it's 10,000 miles long and involves more than a dozen states, two countries, and a couple or three Canadian Provinces. There's several hundred miles of gravel involved too. Just how many tires can you carry on that GX'er, and how fast can you change them on the road?

I've seen 'Busa guys do this, I think up to 245s... completely ruins the appeal of a motorcycle to me... but I guess when you've got a 'Busa, all you can really do is go in a straight line, anyways. And I don't see how it could handle better. It's probably a bitch to get it to lean in and once you get it to, you're just pulling more rubber off of the road the harder you lean. There's a reason motorcycle tires evolved to be rounded...

Why doesn't he just buy a trike and be done with it. It sounds like wrestling a bear getting this thing to corner correctly or at all.

It's made to cruise. That's what I bought it for, that's what I use it for. It corners remarkably well among the heavy cruisers, but it's still a heavy cruiser.
That's what he said...it's a Valkyrie.

I wouldn't do it, but i can see why one might. It does have some advantages for a cruiser, for sure. But if you're gonna pull any lateral g's it would be pretty dangerous. Plus i just don't think it looks very good. But hey...somebody's gotta do it. And i don't think he's completely dumb for doing it.

I drove from Amarillo to Santa Fe earlier this week. That tire would have been fine out there, but never around here.

Most cruiser riders have such a lack of cornering clearance anyway, I don't see the liability of a car tire. I mean, when you are dragging pegs and exhaust at anything more than a walking pace, what's the difference?

Robert E. Fulton went around the world with car tires mounted front and back... it was 1932..so there was no tire rack...and he was in places that never heard of a motorcycle..but that's the whole fun of it isn't it?

http://www.amazon.ca/One-Man-Caravan-Robert-Fulton/dp/1884313051

He does kind of have a point about tire life. Assuming, of course, that you ignore inflation completely and barely mention the niche market factor (as he does) the rise in price for no increase in miles travelled before change means that motorcycle tires are a little more expensive.

But then, you also have to consider that most people DON'T ride their bikes everywhere. So maybe 8 - 10,000 miles is enough for a year or more of riding. I know around here, I'm one of maybe four people who can be seen riding year 'round. Plus the occasional hardy soul who takes advantage of an unusually warm winter day.

I guess it's all in what you want and how much effort you're willing to undertake.

it is nothing new they have been doing that in Japan for years...mostly with scooters. My buddy with a Silverwing has one on his back tire. It is for show nothing more, and it last longer for burn outs too. It handles funny and if you hit a bump the bike will tilt to one side (titer toter) besides go up.