I'm looking to replace my tires on my 2009 Cannondale CX-9. Right now I have Maxxis Raze tires, size 700x35. I'm looking to replace them with a tire with less tread, slicks, and they will mainly be used on my rollers for when the weather gets too cold and I wimp out. But I would like the tire to be good enough so when spring comes and there is a pretty desent day and I feel like riding outside, I don't have to change tires. I really don't care if I go down a size or 2, but I really don't want to drop all the way down to 23c. Any help would be great!!!!