Magura Durin Marathon 120

By Karl Rosengarth

Travel: 90/120mm, externally adjustable
Weight: 3.5lbs.
Stanchion Diameter: 32mm
Steerer: 1 1/8″
Spring Type: Air
Damping: Albert Select oil damping
External Adjustments: Air spring, travel, rebound, compression
Compression Lockout: Albert Select adjustable platform
Disc mount: 6″ postmount
Price: $869
Country of Origin: Germany
Website: www.magura.com

Magura designed the Durin Marathon 120 with the epic racer or rider in mind. I like long rides, and I just happen to have a sweet carbon Trek Fuel EX demo bike that matches up well, travel-wise and intended use-wise, with the Durin Marathon 120. Let’s get it on.

Unscrewing the metal valve cap atop the left leg reveals a Schrader valve that’s used to pressurize the air spring. Rebound damping is controlled by a knurled aluminum knob at the bottom of the right leg. Atop the right leg are the Albert Select platform controls: the outer blue aluminum knob that switches the compression damping circuit on or off, and the inner gold aluminum knob that sets the compression damping platform threshold level. The Flight Control Remote (FCR) is a handlebar-mount thumb-lever that controls the switch between the fork’s 120mm and 90mm travel modes.

Combining a main air spring with an adjustable platform makes for a highly tunable fork. For all-around riding, I pumped up the fork to normal air pressure and set the Albert Select gold “threshold” knob to a firm setting. With that set-up, a twist of the larger blue knob turned on the platform and eliminated fork bob, which came in handy for hard sprints or out of saddle climbs. I also found that I could achieve a more plush set-up by running at the lower end of recommend air pressure and switching on the Albert Select, with just enough platform to keep the fork from sagging under my weight. In this second case, the dialed-down platform allowed the fork to react to small trail bumps, and the lowered air pressure produced a softer ride. Beyond the two aforementioned examples, the Durin Marathon 120 should offer plenty of adjustability for the knob-twiddlers in the crowd.

When the Albert Select was turned on, I noted that the fork made a subtle, low-pitched squawking sound as it cycled. When I asked Magura about it they told me: “What you describe is the compression valving and the shim stack movement. When the Albert Select is selected, then of course you have a restricted valving scenario, higher fluid pressures under movement and thus the noise. This is normal and mostly not noticed, but it is there. We have been reducing the amount of ‘interface’ between the shim stack and its ‘seat’ so there is less vacuum to open the valves and therefore less or no more noticeable noise. In fact it’s a running change in production.”

To make the switch from 120mm to 90mm, you depress the handlebar-mounted FCR lever, lean your weight on the bars to compress the fork, then release the FCR lever while the fork still is compressed. Making the switch while moving was a hit-or-miss proposition, so I ended up stopping whenever I needed to switch. To pop back to 120mm, simply press the FCR lever while un-weighting the fork. It’s worth noting that Magura’s travel adjust feature operates by redistributing the air pressures from a “primary” to “secondary” air chamber when the fork moves from 120mm to 90mm. The secondary chamber is a “negative” air chamber, so instead of adding more spring pre-load to the positive chamber, the system increases air pressure to the negative air chamber, which keeps the fork feeling supple.

Magura tells me that their dual arch design resists the tendency for the structure to twist under braking forces, thereby reducing the loads on the axle and more importantly on the bushings, which helps keep the fork supple. I can’t speak quantitatively, but I felt that the the Durin compared favorably to other major-brand shocks that I’ve ridden, with respect to tracking true, feeling supple and resting twisting/flopping. The Durin lead the way through technical rock gardens with all the precision that I’ve come to expect from a top-notch fork. I should mention that the more platform I ran, the less supple the Durin felt. Since I run a platform shock in the rear, that actually worked to my advantage. By synchronizing the on/off switching of my front and rear shock’s platform damping, I was able to keep the bike feeling balanced fore-to-aft. Overall, the Durin Marathon 120 met my expectations. It’s a solid choice for the epic rider and/or racer looking for a highly tunable, great-feeling fork.