I agree with the kevlar tire approach. I've been on Continental Gators for over a year. I've had one flat but it was a strange thing with a 1-1/2" roofing nail the was positioned just so. It took so much force to puncture the tire, I felt I rode up over a rock or a bump. It drove straight into the face of the tire. I got tired of fixing flats when the air temperture was less than 20F. That's hard on the fingers.