What size ice tire

[2001-400ex'er]

What size would work better for ice racing: 18x9.5-8 or 20X11-9. They are Cheng Shin C826 ( Ice Racing Tire ), and I plan on putting one Kold Kutter per lug. I will either be riding a 400ex or Z400.

[81 clark racing]

im runing brand new stock tires on my 400ex 20x10x9 for ice racing an i love them! i have 2 studs per a knob and they hook up exclent