Bluetree, you probably don't want much more than 100 psi in your tires (assuming you're running 700 x 22c tires). I, too, weigh 115 pounds, and that's what my LBS recommended that I run in mine. I haven't had a pinch flat yet! Knock on wood.....

Like you, I don't have the strength to pump them much higher than that anyway. Getting them to 100 is hard enough! I'd ask your LBS, though, just to be sure.

If you're not already doing this, just be sure to top off the pressure before each and every ride. You'll be surprised how much pressure your tires lose after only one ride or from just sitting in your garage.

Kate