I do believe that properly inflated tires make a significant difference (as compared to those that are woefully underinflated) when one is riding a bicycle.
especially up a hill.
say, the back side of big mountain.
especially when you're already 65 miles into your ride and you are a wee bit tired.
of course I speak from experience.
I started my morning with a deadline and a flat tire. a phone call and a hurried flat-fix later, I was out the door and on my way.
which ultimately led to my woefully underinflated tire 65 miles later.
yes, the number one rule of changing a flat tire is to run your finger along the inside of the tire itself to see if there's a little thorn/piece of glass/sharp something/owie that poked its way into your tube.
yes, sometimes yours truly, when in a hurry, forgets the number one rule of changing a flat tire.
what kills me is just how long it took me to figure out that my tire was bulging out and gripping 5 times as much pavement as it needed to, dramatically (and exhaustingly) increasing my rolling resistance.
when I finally had to pull over and stop halfway up my climb because I was exhausted, I just happened to notice my incredibly soft front tire. geez. it was hot, I was beat, and I wasn't about to change the darn thing out so I just pulled out my cartridge and pumped the tire up, praying it would get me home.
at the top of the hill the tire still felt firm enough, and at the top of the next hill it felt good enough to get me home, so I let it be and cruised on home.
where I proceeded to do a little research into tire inflation, and learned that I've probably been overinflating my tires for quite some time.
if you'd like to check your own process out, here are some helpful pages:
bicycle tires and tubes with sheldon brown
and to just top off my educational day, I learned (from the first link above) that I don't need to worry about my bike ever, ever hydroplaning.
what a great day.
off to check that my tires are inflated to 96 psi in the front and 104 psi in the back . . .