Bootfitter's Notes: Dynafit Mercury Review

Backcountry boots are improving at a rapid pace in today’s market, with several plastic options that allow manufacturers to make boots lighter, and ski better than ever before. Also engineering designs are improving the cuff articulation so the boots are going uphill better than ever before, while also locking down with a more solid connection on the downhill.

Start Haus Owner Jim Schaffner skinning up Hidden Peak on Tahoe's west shore in the Dynafit Mercury.

Dynafit has always been a top manufacturer of alpine touring and backcountry ski boots. They damn-near cornered the market on pin-tech style bindings, although some other manufacturers are setting themselves up for some interesting competition.

As a bootfitter, I’ve always felt like I’ve been fighting an uphill battle making backcountry boots fit well. It seemed as though the serious randonee of AT boot manufacturers had a completely different set of values than performance piste brands. Mostly the difference was in fit; AT boots tended to be more than voluminous, which would work all right if you had a high volume foot. If you were the narrow kind however, your options were less than appealing.

When I was first getting into backcountry skiing five or six years ago, I remember thinking that what I wanted simply didn’t exist: A snug fitting boot that skis well, and has a large cuff articulation.  At the time, most of backcountry boot's fits were way off, and hindered skiing, so it was hard to justify spending hard-earned cash on a product I knew I wouldn’t like. However, in the last few years manufacturer’s have stood up and taken notice the lukewarm reception of their products, heeded the grumblings, and thankfully have started correcting longstanding issues.

Dynafit has had great success with their carbon fiber constructed Vulcan ski boot built in collaboration with pro freerider Eric Hjorleifson as a forward thinking, powder crushing touring machine. At 1,000 bucks, the Vulcan may cause acute angina, which is most likely why Dyanfit released the less expensive and just slightly heavier Dynafit Mercury (at a more reasonable $799) which we’ve been carrying and doing quite well with at the Start Haus. The Mercury has the same great fit as the Vulcan and uses the same unique walk feature.

The Mercury has an enormous 60 degree range of motion forward and back, achieved by releasing the locking upper buckle, and with a removable Downhill Booster Tongue, the Mercury beefs up enough to ski fat boards on the way down. The fit of the Mercury is precise and snug, and will fit those with somewhat narrow feet best. Grilamid plastic keeps the weight of the Mercury down (1600 grams according to Dynafit’s website) and keeps the boot quite stiff. As a bootfitter, Grilamid has quickly become our favorite material to work on for backcountry boot construction. If you need additional boot work, we can heat and punch Grilamid plastic with better results than Pebax plastic, and is more difficult to destroy than Triax plastic (which is somewhat delicate). Grilamid takes heat and punches quite well, and can also be ground out with a Dremel, although the walls are quite thin, there’s probably not enough material to remove to make a huge difference, but sometimes a millimeter or two is enough for relief.

The removable tongue is an interesting design, and is important to note that without proper demonstration the boot can appear delicate or confusing. In theory one would remove the tongue and open the Ultra Lock System 2.0 buckle on the way up. Once on the top of the objective, the skier would simply reinsert the tongue lock the buckle to engage downhill mode. Dynafit’s simple solution offers for a tremendous amount of cuff rotation, making bigger objectives and longer tours far more comfortable than boots with less articulation.

At this point the Mercury has been out for a couple of years and is proven as a great performing and great skiing boot trusted by many of the top backcountry skiers on the planet, if you’re in the market for a new AT boot, make sure trying on a Mercury is part of the selection process.