It's called the "Armour," and it integrates the now-popular protective tire insert with an inner tube to, as the press kit says: "...give the rider better flat protection and the ability to ride at lower PSIs without ever getting a pinch flat."
For a while, I thought those were the very reasons that we abandoned inner-tubes in favor of tubeless tires, but that's just me. In a few weeks, a consortium of two tire makers - Tannus
, which specializes in manufacturing airless cycling tires, and Vittoria
, a high-end pneumatic tire producer - will be releasing a hybrid, inflatable liner that could spell the end of tubeless mountain bike tires - or not.
The Tannus Armour insert is 15 millimeters thick beneath the tread and tapers down to 2 millimeters as it completely surrounds the basic inner-tube. Armour's maker claims that the hybrid solution is easier to install than the most popular tire inserts and more effective in preventing punctures. In their words:
The Armour design allows riders to lower their PSI to as low as 20 psi, whilst at the same time ensuring ultimate protection to their rims. In the unlikely event you get flat tyre, you can also run flat on the Armour without any problems under 10km/h; which could be a real lifesaver. The most noticeable thing about the Armour is its simplicity. Anyone who has installed or ridden tubeless will testify that it is a pain to install and maintain, whilst only being about 60-70% effective against punctures. In contrast, the Armour installation is as easy to set up as a standard tyre / tube combo and requires no special tools or added maintenance.History Being Made - or Revisited?
The Armour concept flips the wisdom of conventional tire-liner makers up-side down. Inserts like Flat Tire Defender and Cush Core are intended to sit against the rim of a tubeless tire, while leaving an air space above to allow the tire carcass some natural flexibility with which to find grip and roll more effortlessly. Conventional inserts create a "bump-stop" for the tire that helps activate the suspension sooner and protect against carcass-tear pinch flats. Puncture resistance is handled by liquid sealant.
Thorn-proof tubes have yet to live up to their name. Katie Bradshaw photo
Armour inserts, however, are compressed against the tire's carcass by the inner tube, which forces the foam element to conform to the terrain at all times. Puncture protection is only as good as the thickness of the insert. Air pressure inside the inner-tube only plays a supporting role to the liner, which should create a noticeably different (albeit harsher) ride quality. The Armour concept is more civilized version of MrWolf's SmartMousse, which takes it to the extreme, with a tiny tube inside a blob of foam that fills the entire tire.
All things considered, the simple addition of an inner-tube to a tubeless tire adds a measurable amount of stiffness to the tire casing - and that lateral support, along with puncture resistance, is high on the wish list for many enduro-type riders. Armour hybrid inserts could be a legitimate performance innovation - or they could turn out to be a satanic reincarnation of the the old-school "thorn-proof" inner-tube. Speculation aside, we will be testing a set soon.