“Maintenance-free” is one of those concepts that, like perpetual motion or extracting sunbeams from cucumbers, generally seems unrealistic at best and the preserve of the thoroughly bonkers at worst. But that’s what Magura is promising for its new MX rear shock.
You can tell by looking at it that the MX is not like other shocks, but what you can’t see is that it doesn’t have any oil in it. As well as the commonplace air spring, the MX also uses air for damping. This in itself is not a new idea, having been tried (with varying degrees of success) by Cane Creek in rear shocks and Englund in forks. What is new is that the MX doesn’t rely on conventional seals to keep all the air in.
Magura hasn’t released actual details of how it all works, but you can get a good idea from the picture. Instead of a rigid air can with a seal at one end, the MX uses a rubber bladder to contain the air, an arrangement that reminds us (very, very slightly) of the Firestone truck-spring air bladder that Merlin used on one of its early full-suspension prototypes. As the MX compresses, the rubber wedge that you can see at one end deforms the bladder, effectively reducing its volume and thus compressing the air within. One potential downside with this arrangement is that the bladder walls become displaced outwards under compression, increasing the diameter of the shock and possibly leading to packaging issues on some frames, but we’ll have to wait and see on that one.
It’s impossible to discern anything about the damping arrangement, although we’d imagine that some very small holes are involved somewhere. Adjustments are kept super-simple, with just an air valve and a rebound damping adjuster. There are no platform-style damping gubbinses, with Magura pitching the MX at bikes that don’t rely on such things.
With no oil and no seals under pressure, there’s no need to have the MX regularly serviced. Maintenance-free is a bold claim, but it’s certainly hard to see what (apart from a ruptured bladder) could go wrong. Whether performance is up to the standards of more conventional air sprung/oil damped shocks is an open question, although with no seals the MX should certainly be almost entirely lacking in stiction and therefore very sensitive over small bumps. Again, we’ll have to wait and see.
Claimed weight for a 165mm (38mm stroke) shock is 195g (0.43lb). Magura will also be offering 190 and 200mm shocks, both with 50mm stroke. The MX will also feature spherical bearings in the mounting hardware to help it to deal with any slight frame/swingarm misalignment. It’s aimed at XC, enduro and all-mountain applications.
Production of the MX is due to start in March – we’ll keep you posted on UK availability and pricing. In the meantime, you may be able to glean further details at www.magura.com.