So I bought a bike today - my first road bike. It's an '87 Schwinn Traveler, in good shape, needs a few tweaks but I'm happy with it. I took it out to see how I liked it, and I only ran into one problem: the bolt at the right rear dropout (it's horizontal) is apparently loose, no matter how much I tighten it. When I put a lot of pressure on the pedals (which I know I shouldn't do - I'm still learning about shifting, especially since the gears are downtube...a bit awkward for me) the wheel seems to slip ever so slightly, causing the tire to rub against the left seatstay. I don't know what I can do to keep this from happening, aside from just trying to be gentler on it...but I'd really like to not have to worry about it.
Here's an album with pictures of the bike as a whole and several of the problem bolt. http://imgur.com/a/NUCIl#gPXwI
I hope you all can help!