[Christ]

Well, see what you can do for now with what you have. Get it working, upgrade later.

Like, if you can find some 5/8" aluminum tubing later on, it's lighter than the steel you have for handle bars right now, and fairly easy to make decent bends around an old bike rim. You might find it free, too.

There are several places that you can lighten frames by literally cutting holes in it, but I don't usually recommend it, especially if you're going to add stress to it. They're usually pretty over-engineered, though.

Another thing that can really affect you is proper maintenance. Make sure you have lightweight grease in the bearings, and make sure they're not overly worn, or if you're unsure, replace them.

Ensure that you don't have tires with lugs on them, since you're not going to rough terrain. If you can find smooth tires, they'll be easier on you. You can get them at K-mart for around $10 each, usually. Bell brand.