What are the advantages to large rear street bike tires?

Really there are none besides looks.Fat rear tires combined with thinner front ones don't handle all that well on curves.

There isn't any advantage outside of a dragstrip.

All you have to do is look at the best handling and fastest bikes out there. If a big fat rear tire was some great benefit in handling, a GSXR750 would have one. If they were more comfortable, they would be on Ultraglides.

They actually make your bike slower because of all the rotational inertia needed to get it turning, and then it's just as hard to make it stop turning when you wan't to slow down. Also, unsprung weight is terrible when it comes to dealing with road imperfections.

Huge rear tires are part of the whole neochopper scene, and that seems to be fading a little bit as the bobber look gets more and more attention from custom builders.

Sometimes the buyers fantasy becomes part of the marketing ploy. After all, good sales are very important. Good handling and fuel economy be dammed.

Most of us have played hand held or computer games which feature motorcycle races. Somehow a larger rear, grabs attention as little else and one automatically assumes that it must be good BUT it is not so.

Only if the engine power and other geometry demands, the fatter tyre, is it justified. Not otherwise.

It all comes back from racing. Manufacturers fit what they deem to be the best width of tyre on a specific bike. Fitting a wider rear tyre than standard will affect the steering of the bike. A 180 section tyre does not really have a bigger contact patch than a 160 section tyre. its only gonna be about the size of the palm of your hand.

Use the recommended max tire width size comparative to your rim size or it will just look cool and not utilize the outer portion of the over-sized tire.You may loose traction in turns if you install the incorrect tire for your rim.If you want to go"Fat"then you will need to change to a wider rim also.

this is the drive wheel so traction will be improved and a smoother ride (compared to a thinner wheel on same bike) due to the lager surface area other than that they just look cool

none, i run a 90 front and a 150 rear, and think they could be much closer

None and real wide is dangerous

I guess if you scoot around town and do a few twisties here and around the 7-11 it must be just for looks, so what's a thousand miles a year anyway?

Now if you actually ride your machine more then an hour a week then you know it provides better cushion and better grab with better braking. Or you could agree with the answers above by some rather questionable - ride to corner, turn around, and go home I'm a pro rider posters above...