Jim from Warrensburg on 4/13/2013 12:44:03 PM:
As I look over the comments, I wonder how much trail conditions have changed since the question was first posed a few years ago, or how much tires have improved. I have a Schwinn 4130, on older road bike with 27 inch tires and 1-1/4 tires, equating to just under 32 mm. I have ridden the Katy from Clinton to Pilot Grove, various segments many times. Not only is the Katy possible on a road bike, I find it to be much more enjoyable then on my mountain bike. You can move faster with less effort, covering more ground and seeing more in a given period of time.
Last year, I had a number of flat tires, ALL of which occurred on actual roads. Not one on the Katy. This with the cheapest possible Kendas. This year, I am using Schwalbe Greenguards, which are supposed to much more puncture resistant, not because of trail conditions, but because of road conditions. I have found far more hazards along roads by far than along the Katy.
My advice? Yes, you can take a road bike on the Katy. As with anything, check current weather conditions, ensure you have good tires and regardless where you ride, plan for emergencies. Happy Riding, and I hope to see you on the trail!