KTM’s Air-Shock Shock

Martin Child

Those with a very keen eye might have seen an item of high-tech exotica tucked between the subframe rails of Ryan Dungey’s KTM 450SX-F at Anaheim 1, the opening round of the 2013 Monster Energy AMA Supercross, an FIM World Championship.

Instead of the WP’s ‘normal’ PDS shock, Dungey’s bike ran an air shock – technology that’s used on everything from mountain bikes to trucks. Although not new to the world of MX (Fox had an air shock back in the 1970s and the recently departed, multi-time world champ Georges Jobe worked with KTM on the project at the turn of the Millennium), it’s an indication of the Austrian company’s faith in the updated technology, as they chose to debut it in such a public and pressure-filled arena.

Details (as you’d expect from a project with Top Secret written all over it) are scant, but it’s believed that KTM (working in conjunction with WP) has found a solution to the Achilles’ heel of air shocks – excessive heat build-up that alters the pressure inside the unit. Just like the end of a bicycle pump warms up while inflating the tyres on your brother’s BMX, the constant pumping of the rear shock has traditionally heated-up the air inside. Previous attempts to eradicate this problem have come in the form of two bladders (one for low-speed control and one for high) or one-way valves that let the built-up pressure vent to atmosphere. It’s not immediately clear which system (if either) KTM and WP, have employed. The only clues are the braided lines that run to the air box. These will either be hydraulic lines or hide electrical cables to a secret “brain”.

The advantages are clear. If KTM get their system right, they’ll save weight with the unit and have an infinitely adjustable unit that can be altered on the bike. Dungey has been overheard to be in praise of the new-gen air shock, especially through whoops, which is where the former AMA SX champ struggled on the KTM in season 2012. Watch this space for updates as we find out more.