Steel frames

Wow, lots of concerns. First off, there are a lot of different quality levels in "steel" bicycles. You want to stay away from High Tensile Steel bicycle frames. They also use "Hi-Ten" and also just "Steel". The better steel frames are labeled Chrome-Moly, Chrome Molybdenum, or Manganese Molybdenum. These are the finest steel alloys for bicycle frames and are made by Reynolds, Columbus, Dedacciai, True Temper, Ritchie, Tange, and Ishiwata. Look for a frame with decals from these manufacturers, usually located either high or low on the seat tube. Occasionally they will be located on the top tube right behind the head tube. You might find some frames that say that the three main tubes are Chrome Moly with the others being High Tensile steel. They are better than all High Tensile steel frames but are still not as good as an all chrome-moly frame.

Another thing to look for is butted tubing. If the tubing is butted, it will say so on one of the decals. Butted tubing is where the tubing is drawn with different wall thicknesses so that it is thicker in areas that experience more stress an less thick in areas that are not subject to a lot of stress. This makes the frame lighter and is usually found on the highest quality frames.

Lugs do make a stronger frame. It is not really easier to repair a lugged frame but the repair is less evident than on a butt welded frame. The downside to lugs is that they are little harder to clean where the tubes enter the lugs. That is taken care of by just paying a little more attention to that area when you are cleaning it.

Stiffer materials having a lower fatigue strength. An aluminum frame has a lower fatigue strength than both Carbon Fiber and steel frames. That is not a big worry though, because a well maintained steel frame will last your lifetime and your children's lifetime. Your grandchildren might have a slight issue with metal fatigue if the bike is ridden a lot.

A NOS frame should be fine. The only concern would be internal corrosion. If the frame was stored in a seaside warehouse for a number of years, there might be some corrosion problems. Looking down into the seat tube with a flashlight will show if there is any internal corrosion as this is where it shows up first.

There are no issues with using a steel frame with STI shifters. There are adapters that can be attached to the DT shifter lugs that act as cable stops for use with STI shifters.

I think that you may have misinterpreted your bicycle science book. What it means is that if you have a frame like the traditional "girls" bicycle that lacks a horizontal top tube, it will have less structural strength than a frame that has a traditional "triangular" frame. The only frames that have a perfect triangular shape are very small frames. Larger frames will always have the top tube and down tube separated at different areas on the head tube. This is a non-issue, otherwise nearly every bike manufactured would be structurally unsound.

Just a reminder, make sure that you know what size bike you need before you go buying one. And make sure that you have some funds budget ted for a helmet, gloves, and cycling shorts.

+ 1
also check out the Bianchi Vigorelli, its a very good modern-looking steel bike, at a right prize for the way it is equipped too,
http://www.cyclingforums.com/forum/thread/485232/best-steel-road-bike-to-buy-build-for-1500/15#post_4002780

I just had a custom steel frame built and couldn't be happier. It combines lugs and fillet brazing (of the bottom bracket). It rides like a dream. I chose to go with steel because I had a very bad accident about 20 years ago on another steel bike that would have broken in two if it was aluminum or carbon. And on that note: Yes lugged frames are easier to repair and stronger after repair than a welded frame, basically because you don't have to re-weld the joint. This isn't absolute tho. It all depends on the factors of the accident.

If youre buying a steel frame, look for good tubing, such as Reynolds, Columbus, Dedacciai. I have a Trek 720 Touring bike with Reynolds 531, The above-mentioned Saso sport bike with a combination of Columbus, True Temper and Tange (the joys of custom!), and am currently building up a Ciöcc 12.5 COM frame thats named after the tubing it uses: Dedacciai 12.5 COM. They all have their own properties, advantages, disadvantages. Personally I like thin-walled tubing, but others don't, such as lovers of the Surly Long Haul Trucker which is aircraft-grade chromo, nice and thick to handle the apocalypse.

As you drill further down to the selections you like, it would probably be best to ask on the forum about the specific tubing that the bike is made of and you'll get lots of responses.

A FANTASTIC resource is at Rivendell bike's website, steel lovers to the core. rivbike.comframe materialsOpen ↗

BikeDirect has some reasonably priced steel frame road bikes.