Ok, not really flat. I've got a Specialized Crossroads Sport with 700x45 tires. The sidewall says 55-80 psi. I pumped the tires up to about 75psi based on the gauge of a floor pump. My gauge is from a HD shop and reads up to 60psi. When I use the gauge it goes past the 60 and pegs so I believe I have 65-70 psi or so in the tire. By feel, it's hard as a rock. Anyway, when I am on the bike and I look down and back at the tire it looks almost flat. I am about 235 pounds so it's carrying a lot of weight. I know I'm not riding on a flat tire but wonder if I need to get it up to 80psi or if it's ok as is.