A few things to look for before needing to dig any deeper (if ya dont' see 'em, pass)

1. a bike-shop or boutique name (Peugeot, Raleigh, Bottecchia, Fuji, etc)
2. a 3 piece crank - if it's cottered, expect either old, or heavy, or both, but don't necessarily indicate poor quality. This will involve some digging on your part
3. Does it have safety levers? A lot of decent bikes did, but no high-end bikes had them. Keep it in mind
4. What size/type of wheels? If you're looking for a road bike built after 1965 or so, you'd be looking for 27" or 700c aluminum rims. If you're going with an upright, "English 3 speed" style bike, 26X1-3/8 is most common, with 28X1-1/2 being less so. Cheap department store roadbikes sometimes had 26X1-3/8 steel wheels, and after a certain age (again, mid-60's), most better bikes had aluminum wheels.


The thing about it is that if you like a certain bike, it doesn't matter what the quality is. One of my best riding bikes (to me) is a Peugeot that was bottom of the line when it was built. It's heavy and slow, but it's very, very comfortable. Matter of fact, with one notable exception, nearly all of my bikes were mid-range models, and I'm perfectly happy with them.



That said, given the chance to get a Raleigh International or a PX-10, I wouldn't turn up my nose.