What is an open tubular tire?
I was doing some research into what the heck an "open tubular" is, and came up with this info from manufacturer Challenge.
Take it as marketing hype or not. I suppose with any term that is open to interpretation, it may mean a higher quality tire with some manufacturers, but not with others. However, it seems to me the distinction between vulcanized or non-vulcanized is a significant one.
I can say for a fact that riding around this winter on 33mm file-tread tubulars has been an eye-opening experience, and I would very much like to transfer that kind of ride quality to my "main" bike!
An Open Tubular is a tubular that is assembled on the wheel like a standard clincher. The shape in fact is that of a clincher, but the materials used to make it (compound, high TPI carcass) but above all the hand made production process (tread glued by hand on the carcass and no vulcanization process involved at any time) is exactly the same of the tubular.
Therefore the Open Tubular is an extraordinary compromise: a clincher with a tubular-like superior comfort and best road feel, much higher than any other clincher, mainly if a soft latex inner tube is used.
About the price, the Open (open + latex tube) is usually more expensive than a clincher but much cheaper than a tubular.
Since carbon fiber frames are getting so popular, it has become even more important to ride on high quality tires. The road feel given by an Open Tubular with latex inner tube helps the rigid carbon bike to behave in a more comfortable way, absorbing vibrations and transferring to the rider a better quality ride feel from the bike in general.
Be aware that some manufacturers may call "Open Tubulars" some of their standard clinchers in order to sell them at a higher price. You can recognize a real open by the TPI first of all (that needs to be the same of a tubular) and by the softness and flexibility of the tire when you touch it.