Dynafit Tech Heel Inserts — Part 2 — State of the Union

Part 1, Toe Fittings
Part 3, Manufacturing

Compared to the brain swelling complexity of “tech” toe fittings used in ski touring boots (stay tuned for additional reports, making them isn’t easy), heel fittings haven’t been through much evolution until recently. We like the new Master Step version as it appears to enjoy a steroid enhanced connection to the boot. But the earlier “standard” heel fittings, properly maintained, did fine for millions of skiers over decades of use (with exceptions we mention below). Herein, the basics for those of you new to ski touring gear: we report on what Dynafit will be supplying for tech heel boot fittings, 2017 and onward. (Please note this post was made possible by Dynafit financial support, while we retain 100% editorial control.)

Historical note: Other than very early prototypes, the original retail Low Tech heel fittings invented by Fritz Barthel we’re virtually the same thing as what’s presently the “Standard” fitting. This is the steel lug you’ll find embedded in the heels of literally millions of ski touring boots manufactured over the past thirty years. Considering its minimal attachment (small screw and a couple of pins pressed into holes) it was amazing how few people experienced failure of this part.

Nonetheless, the fitting coming off the boot heel has not been an unknown occurrence. This especially so for ski mountaineers who spend time off skis, hiking in rough rocky terrain where the fitting can be pried or otherwise peeled as if attacked by tiny destructo-gremlins hiding in the rocks. (Yes Virginia, gremlins exist, if you have standard tech fittings and use your boots hard, we continue to recommend yearly maintenance).

The standard rear fittings always worked for us — but the new ones are looking super nice. Both the Master Step and Master Step Light “bolt” into the boot internally. That’s a much better configuration than the sometimes fragile, single tiny screw of the standard fitting. Further, the full Master Step fitting boasts four anchor prongs. Fair to say it’s “twice as strong,” as Dynafit states. (We experimented some time ago with retrofitting a through-bolt for the heel fitting, was interesting.)

The added strength of Master Step is particularly important for the “free touring” segment of the sport, as aggressive skiing by strong athletes can demand binding retention settings that verge on astronomical — sometimes providing a max setting of “DIN” 16. That corresponds to 160 Nm torque, or 118 foot pounds. That’s equivalent of applying 118 pounds of your body weight to a 1 foot long pry bar. (Note, the regular Master Step fitting (not the light version) is also said by Dynafit to “step into the Beast 14 and 16 bindings _without_ a Power Insert heel adapter.)

Clearly, Master Step fittings will hold you in. On the other hand, it’s worth mentioning that in terms of release and retention, they perform exactly the same as the standard tech fitting. Read on.

Ski touring boot heel tech fittings function as a “wedge” in release modes. If you take a fall and need a forward-upward release at the heel, the fitting is pulled up between the two horizontal binding pins of what we call “classic” tech bindings. The pins spread under tension, allowing you to pop out. This is a smart, minimalist system, but suffers one indigenous challenge. Most ski bindings allow quite a bit of vertical elasticity at the heel, before release occurs. This serves as a shock absorption system for typical loads your body puts on the binding while you’re racing downhill. Tech bindings using the fittings illustrated here have markedly limited vertical elastic travel at the heel.

Thus, while most skiers infrequently (or never) experience problems caused by this, stronger athletes who ski aggressively may release out of the binding accidentally unless the binding heel is set at higher tensions than that same skier could use with a binding having better travel-elasticity. Such bindings would include nearly any alpine skiing binding, as well as a few hybrid touring bindings.

I mention the elasticity issue to be complete. It’s not a deal breaker for most skiers, and indeed a recent trend to “retro” type tech bindings (e.g. Dynafit Speedfit & TLT Speed) shows how wonderful the original system is. Indeed, for the most efficient human powered skiing, using the “classic” tech binding mechanics with two pins at the boot heel is what we continue to recommend. It’s how you’ll get the lightest and most efficient bindings under your feet. At least for now. In a few years, who knows?

Meanwhile, nice improvements on the Master Step fittings — especially the heel. If you’re interested in more backstory, check out this early prototype Low Tech (Dynafit) ski touring binding.

Sidebar: For readers new to ski touring, a photo review. Basic ski touring boot with tech fittings at toe and heel. Rear fitting here is a “standard,” used industry wide before Master Step. At the toe, a Quick Step In (QSI), identified by the small notch below the fitting socket. These are somewhat easier to step into, but not greatly so. Most of using tech bindings efficiently and gracefully is about practicing techniques for entry and exit. Most require a bit more “English” (or is that German?) than step-in type bindings that snap a clamp down on the heel of your boot.

14 Responses to “Dynafit Tech Heel Inserts — Part 2 — State of the Union”

1. XXX_er September 5th, 2017 11:08 am

   ” Most of using tech bindings efficiently and gracefully is about practicing techniques for entry and exit. ”

   that ^^ would be a good subject for an artical maybe even some movies

   I think the reason some skiers lock out their bindings is that they don’t observe and develop the proper snow-clearing protocol

   so miss it once, the
   ski falls off and they complain about tech bindings falling off

2. Stokes September 5th, 2017 11:42 am

   ^ I agree. See far too many (nearly all) users stepping into bingings and setting off before cycling through a simulated ‘tour step’ to clear the sockets.

3. See September 5th, 2017 7:02 pm

   I use tech bindings. I like them, and I rarely lock them out. But I have had a few experiences where I’m pretty sure they were prereleasing at the toe because chatter inducing conditions were overcoming the toe spring tension, not because I had failed to clear ice from the sockets/under the toe arms. In my experience, this problem only occurs under certain firm conditions. It isn’t something I worry about most of the time. But I believe it is a real phenomenon, at least with older Dynafit bindings (the only ones I’ve experienced this with). Of course, maybe it’s just me, but the fact that this question hasn’t been decisively resolved after countless skier hours on tech bindings is kind of my point re. data.

4. Rob September 6th, 2017 1:39 am

   Are this year’s boots (2017/18) all going to be equipped with the new heel inserts? Or at least most of them? Do you know if the Maestrale RS2 is?

5. Rob September 6th, 2017 1:45 am

   Does that mean that the only reason for the Beast heel inserts was that the original heel insert might get pulled out while using the Beast bindings? Or are there other modifications to the shape of this new heel insert?

6. Lou Dawson 2 September 6th, 2017 8:02 am

   Rob, the Beast heel inserts served two purposes, they were stronger, but apparently they also protected the boot heel shelf from possible damage when using Beast bindings. Master Step is a bit thicker than the “Standard” fitting but it doesn’t appear to do what the “Power Insert” did in terms of creating a steel rim and shelf.

   The question is a bit moot, as all Beast bindings are discontinued, though a few are still in the retail pipeline.

   Not sure if I made it clear, but there are two versions of the Master Step heel fitting. They look the same from the outside near as I can tell, but one has 4 anchor prongs and the other has two, and is called the “Master Step Light.” Any of the lighter weight Dynafit boots will probably have the “Light” version.

   Regarding Scarpa and other brands, for 2017-2018 you’ll only find Master Step fittings in Dynafit boots, Scarpa will continue to use QSI, and other boots using “Certifed” fittings will have the standard version. This according to Dynafit folks.

   Lou

7. Lou Dawson 2 September 6th, 2017 8:03 am

   You guys reminded me… i need to do a basic comparison photo of the old and new fittings. I’ll get on that! No rest here! (smile)

   Lou

8. Mark W September 6th, 2017 11:56 am

   So, can older boots be retrofitted with the new fittings? Just curious. I did have a heel fitting failure once, and it wasn’t super fun; pseudo-telemark turns followed the loss of fitting in the backcountry.

9. Lou Dawson 2 September 6th, 2017 12:23 pm

   Hi Mark, nope, no retrofitting due to the entirely different way the Master Step is fastened to the boot. Lou

10. Lou Dawson 2 September 7th, 2017 8:47 am

    I got the word on what brands of boots while have, what…

    For 2017-2018 you’ll only find Master Step fittings in Dynafit boots, Scarpa will continue to use QSI, and other boots using “Certified” fittings will have the standard version. This according to Dynafit folks.

    Newcomers to the sport, note that the majority of non certified fittings are perfectly fine, but all fittings should be bench tested before leaving the ski shop.

11. Rob September 7th, 2017 1:52 pm

    Yeah I saw some photos of the RS2 and it looks like the old fitting. Thanks for confirming.

    And the reason I was asking about the Beast compatibility is because I have a pair of Beast 16, that I hadn’t mounted anywhere yet, partly because I didn’t want to put the insert on my boots.

12. Mark W September 12th, 2017 8:44 am

    Yeah, if figured the older boots couldn’t be retrofitted for the new fittings given the way their affixed within the heel.

13. Jeff November 29th, 2017 6:12 pm

    Lou, your caption on the Beast Power Insert mentions that it’s compatible with any classic tech binding – is that the case? I’ve been reading up on this because I’m looking at a used setup with Beast 16s that would require I install the insert. I’m concerned about compatibility/usability down the road if I want to use another binding. Was a bit (pleasantly) surprised to see this definitive statement. I assume it’s contingent on properly spacing the heel and binding on a future setup. Since I have you here, are boots at all compromised after the insert is removed? Does one just plug the holes? And any word on drilling into the tech pads of a Solomon quest boot – I think I’ll be ok, but haven’t seen anyone do it. Thanks so much! (first time posting, but have really appreciated this site over the past year or so).

14. Nad February 7th, 2018 11:46 am

    Does anyone know where to purchase the inserts without rubber, sole or boot?