[scootter]

Nitto has the 315/35 rear and 275/40 front which are close to 26". With the twelve inch rear you could run a 335. I have the Michelin Pilots which are no longer made, but they make the PS2 in the same size.
Kuhmo Ecsta XS(Extreme Performance Summer) 235/45R17 is 8" tread and they have the 315 rear also. There isn't much in the 17" tires.
Scott