One aftermarket wheel mfg has already confirmed a 180 with 5.5in wide rim happily slots into the 250 that the 400 is based on.
Only weights were posted, no moments of inertia/etc, but OEM 150 tire & 4.5 wheel vs sportier 180 rubber on the forged aluminum 5.5 wheel came out with the 180 setup being slightly lighter, so... I'd expect the OEM 160 setup on the 400 to be slightly heavier due to the slight bump in tire size, so slightly more of a win?
Supersport/superstock on it doesn't interest me in the least, if I'm jumping in it'll be straight over my head full superbike as the target.
Both Bridgestone and Dunlop make slicks that will work on this bike. It's the same thing we've been using on the FZR400s and SV 650s.
When I was racing there was a guy that had put a FZR1000 wheel/tire on his FZR400, think it was a 190. He said it didn't work well, too much for that small a bike, think he went back to stock.
This goes 180 degrees opposite of everything I have understood about bikes and cornering speeds. Simple physics should say that a smaller mass can go around the corner at a higher speed than a larger mass, with the tire contact patch (available grip) being the other variable.
I think there is more of a squaring off the corner approach to bigger bikes (and high HP cars), sacrifice a little corner speed in order to be able to get back to full throttle earlier because that's where the time is. I'm sure that a motogp bike could have the same corner speed as moto3 but that is not the fastest way around the track..
We have trouble keeping heat in the 180s we are required to run in twins cup, and the huge tire sucks up horsepower. A 180 on the 400 would be much worse. A 4.5" Dymag with a 160 or 165 would be perfect.
In my humble mid-pack club racer experience on smaller bikes, I've been passed by some really fast guys on big bikes only to run right up their asses mid corner. Of course, as soon as they can straighten up enough to apply the power they're gone again. I guess it comes down to how you define "corner speed"- is it the average speed thru a corner, the max at apex, or what?
Again, this was a wheel MFG playing around and showing that even upsizing from a 150 to a 180 they could do it and still be lighter. They also offer 4.5in rims allowing for sticking to 160s. If really starting with 80hp at the rear wheel out of the crate, with some room to go up, and it being an inline four instead of a kinder to tires twin, at what HP level does the 180 actually make sense?
I think the more flexy steel belted construction builds and holds heat and it isn't as much as a problem.
I tried Pirelli's SC0 in a 165 when they were playing with it a couple years ago, the twins guys loved it, my FZR would slaughter it in one sprint. I loved the grip for the first 6 laps though. Pirelli rep was on hand, was working with them on setup/etc and just couldn't make it work. Never tried a 180 on the bike.
Probably at a power level that the 400 would never get to. Plenty of tire performance with a 160. Plus, the height and width of the 180 would make setup a pain. The bike already has tiny trail numbers and that tall 180 would make it worse. The forks would probably have to be dropped as low as they could go and they would still be too short.
Braking into the corner and drive out of the corner are different conversations entirely. My comment was about corner speed.
Amazingly enough a simple test with a radar gun JU did long ago proved that the well known fact of smaller bikes cornering faster was well, totally false.