The best protection against punctures is to just get rid of the inner tube altogether, and run your tyres tubeless, right? Maybe. Sure, you’ll have the luxury of running lower tyre pressures, gaining that all-important traction and grip, of particular benefit when riding fresh-cut, natural, loamy trails. But there is a limit to how low a pressure you can run before your tyre sidewalls start buckling in turns. London-based Tannus have a solution to the problem; Armour.
Tannus Armour puncture protection tyre insert
Tannus Armour is a foam insert made with Tannus’ patented foam compound called Aither, engineered and manufactured in Korea. Unlike other foam inserts we’ve seen on the mountain bike market, such as Cushcore, Tannus Armour isn’t designed to be inserted into a tubeless tyre set-up. Rather, it is designed to be used in conjunction with an inner tube. Hold on a second. That’s going to add weight. Yes, it certainly is; 310g for 27.5″ and 320g for 29″ wheels, per insert. Tannus, and Scott from Pedal Addiction Cycles who kindly fitted one for me, say that with the additional side-wall protection provided by the Armour, you can now chose to run tyres with a much lighter casing, saving weight there.
In practical terms, taking the popular Maxxis Minion DHF tyre as an example, the weight difference between the DH and Enduro casing tyre is over 500 grams. When all weight is considered (tube, sealant, valve, Armour insert), you are around 200 grams lighter running the Armour with a tube than you are running a standard tubeless setup. You now have better grip, improved vibration dampening and near 360° protection.
Let’s put that to the test with another popular example. Take a 29″ Maxxis Aggressor for example. The Double Down casing option weighs 1170 grams, while the lighter EXO/TR is just 900 grams. Let’s say, for the sake of argument, that 100 ml of Stans tyre sealant weighs
10 100 grams, and a standard Continental 29″ tube weighs 225 grams. Running the lighter EXO/TR tyre casing with a tube and a Tannus Armour insert brings the weight of your set-up to 1,445 grams. Running a tubeless set-up with the Double Down-cased tyre brings your set-up to 1,180 1270 grams. OK, the Tannus Armour set-up is considerably heavier with this particular example. But we aren’t lycra-clad road cyclists looking to save on every last gram, we are (and when I say we, I mean me) enduro and downhill mountain bikers who are somewhat interested in weight, but far more interested in downhill performance gains and reliable puncture protection.
This is where we see the biggest appeal in Tannus Amour. As it sits flush to the inner tube and sidewalls of the tyre, it offers near 360° of puncture protection. Also, it should provide robust sidewall support to prevent the tyre buckling under laterally-applied force in fast corners. This means you can run your tyre pressure considerably lower than you would for a standard tubeless set-up. Racing on the set-up at a British National Enduro Series round at the weekend, I ran a front tyre pressure of just 14 psi. Happy days. There was definitely at least one significant front wheel case that I would not have gotten away with without the Armour insert, whether running a simple tube set-up or tubeless.
Roger Vieria, who rode the Tannus Armour in the recent World Cup in Maribor had a slice in his sidewall that he only noticed when changing tyres. He said “I have no idea how long I had the sidewall tear but with the Armour it doesn’t matter. If I was riding tubeless it would have gone flat straight away”.
The wings on the sidewall of the Armour are ~2mm thick. They cushion the inner tube upon impact meaning there is never any contact of the tube with the rim, hence no pinch flats. The Armour should also provide additional protection to your rims during super hard hits.
If you were really concerned about the the additional weight, you could always consider forking out on a hardy and lightweight S-Tubo MTB Tubolito inner tube (29″ weighs 45g), bringing your Tannus Armour set-up with the Aggressor tyre down to a much more appealing 1,265 grams, and of an equivalent, if not lighter weight than your traditional tubeless set-up. Now your set-up is more expensive, but perhaps in the long term the initial set-up expense would work out, when you consider that you don’t have to keep topping up your tyres with sealant.
Setting up your tyres with Tannus Armour is pretty simple. After popping one bead of the tyre over the rim, you just insert the Armour into the tyre (with a dusting of baby powder), then insert a lightly inflated tube before popping the other bead of the tyre on. If you have to use tyre levers, you can rest assured that the Armour will prevent you from damaging the inner tube with the edge of the levers.
Pricing and Availability
Retail of the Tannus Armour starts at £29.99 (~$40) and is available in a wide range of sizes, from a 20″ for a folding bike, all the way up to a 29″ x 2.5″.