luke our front tires are 25'1 inches tall, so you can go with a 225-45-17 at 25', as for the rear our tires are 26'1,so you can 255-40-18,at 26'0 or 295-35-18 at 26'1, this should be fine to run on the crossfire but i do not suggest! you will lose all the handling capability, that makes the crossfire stick like glue to the road............hope this helps..............