I started riding 4 years ago, then had our last baby, moved across the country, etc... then started riding again after settling here in Missouri. I upgraded from a Walmart bike to a Trek Skye and broke my leg the first 5 minutes due to my ignorance on psi. I am eyeing the nice, smooth highway 54 with the wide shoulder to ride on instead of our country roads. Though I've never done that either. So, two questions, bear with me... I am wondering if I need to change the psi if I go from one type of road (gravel/dirt) to the other (pavement) during a ride? Also, what psi is recommended for a mountain bike on pavement at 200 lbs? Is there a psi chart or something out there on the internet? I was never nervous about riding a bike before, I just did it but my ignorance cost me. Thanks a lot for your help.