Despite the strong presence of tubeless tires and wheels, there is clearly not only a place for clincher tires with tubes, but a stronger position than expected. One major contributing factor is innovation in tube materials and construction processes. A second is that some people just struggle with tubeless use, whether it's a tire issue, rim issue or a combination, it happens. Schwalbe has partnered with the German chemical products company, BASF to create the Aerothan tube system using Thermoplastic Polyurethane (TPU) that is substantially lighter than Schwalbe's own Ultra Light tubes, but also has proven and inherent puncture protection, and offers much lower rolling resistance found in normal tube-tire interaction. TPU is already being used by a select few other tube makers, but Schwalbe and BASF are delivering some unique features. It is important to know that this is the second generation of the Aerothan concept, and it can be used with rim or disc brakes.

Working as a team, the engineers of the two companies had to combine seemingly opposing goals in the development of Aerothan: lowest weight and highest puncture protection. Schwalbe's Innovation hub is the place the tire company explores material compositions and construction principles with new designs to make entirely new products. Developed in cooperation with BASF and with experts from the German plastic manufacturing industry, the Aerothan tube emerged to not only meet all the requirements of a high-end bicycle tube, but to exceed them. Local extrusion facilities and experts helped to create the end result, and Schwalbe manages all of the process in Germany, with finished construction in their own building. Quality assurance from the chemical composition, to the extrusion and finishing processes is exceptionally high, with stringent German manufacturing standards.

The TPU Aerothan tube is about 40% lighter than light weight tubes, as well as having lower boxed volume. Interestingly, the valve cylinder is actually TPU as well, and carries a threaded removeable valve core. So the entire assembly can be recycled if local facilities allow TPU. You can also use a valve extender if needed. TPU offers some interesting properties in that it is much harder to puncture than a butyl or latex tube. it is also less prone to pinching, so it can handle lower tire pressure better, giving you more psi range with your clinchers. The ride is stable and mildly damped at all pressures, but not negatively. Feel is excellent, in part because TPU won't stick to the inner surface of the tire, which also is the main reason the rolling resistance is low, and more comparable to that of a latex tube. The low surface tension of the material, inside and out, is also why you cannot use tire sealants with the Aerothan, as the sealant won't adhere to the tube. It also will not damage it, so if you use an Aerothan in a tire that previously held sealant, don't worry.

The much greater puncture resistance means the sealant question is somewhat moot, but there is another detail about TPU tubes you need to know. If you normally pre-inflate a tube before installing, you are limited to 4psi with Aerothan, which is plenty to give it a little shape. If you inflate outside the tire over 4psi, it can distort the tube shape, making it worthless. Inside the tire the air is distributed evenly so the tube shapes perfectly inside. And yes, you can remove and re-use the tube. TPU tubes are not inexpensive but the durability and longevity is excellent if installed and taken care of properly. An easy-to-use glueless Aerothan patch kit is available from Schwalbe. As mentioned above, this Aerothan version is certified for high heat, and is safe for rim brake use, as well as disc.