I have an 05 Kodiak with stock tires and rims, What size can I go up to without modifying my Quad? I am looking at going to a 27" on this mahine but if it is going to require mods then I will go to the biggest size I can.

2005 Arctic Cat 650 V2
2500 Warn Winch

2005 Yamaha Kodiak 400
3000 CMT Winch

 

I dont have a kodiak but I took a tape meassure and turned my front wheel in every direction measuring for clearence from the center of the hub. You have to take into wheel travel into account also. Or call a place that sells tires I'm sure they sold tires to kodiak owners before.