I've been riding on 12" Polaris front rims all summer with 24" tires. Awesome on the trail. They just roll over stuff instead of smashing into it. noticeably heavy though. I'm going to go to some Douglas 10" with 23x7x10 Holeshot XCT's on front for next summer.
I'll be going to 22" Bear Claws on the back when my Holeshots wear out. Should be fine if you gear down appropriately. Maybe a 42 or 43 rear sprocket?