OK, put me with Roll-Monroe-Co on this one. Good luck to you. I like my old Speedster but I'm glad I have other bikes.
One weakness that may be a deal breaker for you is the unusual diameter S-6, 597 mm rims. There is only one or maybe two (Kenda, Cheng-Shin) tires (in two colors) made for this rim, and they both compete on low price. They're a little narrower than the original Schwinn tire & I find that they're marginal even for me at 210 lbs. I keep them at 70 psi; a little bit less risks a pinch flat. Regarding max inflation, have to be concerned not only with the strength of the casing but with the bead blowing off the straight-sided rims. And the steel rims give poor braking when wet. There are no modern hook-bead extruded aluminum rims available in the 597 size.
You could put good-quality 590 rims (world standard 26" utility bike size) on the bike, but that's a major expense buying new wheels or still a major expense plus a big job relacing the old hubs to new spokes and rims. And if the brake calipers don't have 3.5 mm additional travel in the slots, you'd have to do something about that too.
What I'm getting to is, you might rather find a good no-suspension mountain bike is a more reasonable basis to start from.
Last edited by duffer1960; 08-20-09 at 03:36 AM.