- Hi Ten: very inexpensive, and very heavy, the lowest quality level of steel used for adult bicycle frames
- Cro-Mo: higher quality alloyed steel, lighter weight than Hi Ten
- Butted Cro-Mo: lighter still, probably the most widely used tubing for mid priced ($650- 750) steel fixed gear bikes. It comes in many, many names, and is usually what’s used in “proprietary” tube sets from many bike manufacturers, to give it a less generic sounding name.
- Reynolds 520 (note- all of the Reynolds tubing listed is butted): Reynold's version of the standard butted Cro-Mo, their entry level butted tube set
- Reynolds 631: the next level up, air hardened, with higher strength and thinner wall thicknesses available
- Reynolds 725: next level up, air hardened and heat treated, with thinner wall thicknesses available
- Reynolds 853: very high end steel, thinner still, and lighter
- Reynolds 953: a variant of stainless steel, this one rivals Ti and carbon fiber on weight, but with the ride of steel
- Columbus Spirit Niobium: similar in weight to the 953, the Spirit is one of the lightest steel tubes sets available
A Rose Is A Rose Is A Rose, right?
Not when it comes to steel tubing for bicycle frames. Does it make a difference, whether it’s Cro-Mo, double butted, heat treated, etc.? You bet. If you intend to actually ride a road bicycle (fixed or geared) for some distance, for the pleasure of riding, it’s really no different than with other products. Cars are probably the best analogy. Is there a difference between how a Honda Civic rides and handles, and how a BMW 3 series rides and handles? They both get you to where you’re going. Again, yes there is a difference. The Honda is a great car, but the Beemer is a lot more fun. That’s the point with the better quality tubing- the bike is just more fun to ride. It can get confusing, with so many types of steel tubing. Through various alloying strategies, heat treatments, etc., steel tubing sets produced by Reynolds, Columbus, True Temper, Kaisei (formerly Ishiwata) and others have gotten progressively stronger and lighter.
In general, you can look at it this way- as the tubing tensile strength increases, the wall thickness of the tubing can be decreased without a sacrifice in strength, producing decidedly lighter tube sets. For the cyclist there are 2 main benefits. The first is obvious, the frame will be lighter. The second is not so obvious until you actually ride the bike using the better quality tubing. The ride feel, the liveliness of the bike, and the ride comfort will all be noticeably improved. IMHO, this is the far greater benefit to the average cyclist, even more so than the weight loss.
So, what is the hierarchy in the world of steel tubing for bike frames? Here’s a generalized overview/ranking (low to high), using the popular Reynolds line to represent the higher quality steels:
I guess the point of this is, when you’re looking at the various bikes out there (and this seems to be especially true of the fixed gear segment where a lot of steel is used), pay attention to the differences in the steel used for the frame. If it doesn’t say Reynolds, Columbus, True Temper, etc., then you can be very certain it is a medium grade of tubing at best. This does not imply that it is of low quality, but simply that the bike just will not be as light or ride as pleasurably as one made with a higher quality tubing. Also, note that even though the higher quality tubing is lighter, in most cases it’s actually stronger than the heavier steels. The only down side (besides cost, of course) is that the thinner walls will dent more easily. So, if your bike will be abused to some degree, it would be better to use the thicker walled tubing.