Tech Ski Boot Fittings — Clicking, Play, Weird Release and other Nefarious Occurrences

Update: January 2013.
Well, by now you’ve all seen the good, the bad and the ugly regarding tech fittings. We had Salomon’s blowout, Garmont at just plain weird, and we’re all pondering how we can have something so critical work across brands with no industry standard other than voluntary attempts to get it right, sometimes by people who appear to have no idea how a tech fitting is supposed to perform.

Now we’ve had a few comments about BD fittings clicking while in use (see below). Truth be told, on occasion over the years I’ve had boots that “clicked” while in touring mode in tech bindings — of various brands. I usually cured the problem by either swapping bindings or boots, usually boots. And the condition was so rare as to be no more than a passing thought. Recently, Tim (see comments below) wrote in about some clicking he’s getting with his BD boots. I went ahead and evaluated some BD ski boots I had lying around here, as well as a new pair of BD boots I borrowed for testing. While one of our BD boot samples could be made to click if we worked super hard at it (it was so intermittent I couldn’t easily video the behavior), the other pair we evaluated were rock solid, as have been our BD test shoes over the past few seasons.

One theory that’s bandied about regarding the click syndrome is that the boot fittings cause the binding to close at an incorrect width. More likely, it’s caused by a particular boot toe tech fitting being slightly of the wrong shape around its outside rim and conical interior.

Out of curiosity, I caliper measured the binding toe wing spread with different boots inserted, in case that might say anything. Nothing really leaps out at me, though the variations are interesting:
New BD Prime – 87.28 mm (works fine)
Almost new BD Swift – 87.49 mm (slight clicking if we work hard to get it)
Used TLT-5 – 86.68 mm (works fine)
New La Sportiva – 87.76 (works fine)
New Garmont Cosmos – 86.26 (no clicking but other problematic behavior)

At the most, I’d regard this as a boot warranty issue and would suggest if you do experience annoying clicking while in tour or alpine mode, you swap your boots out on warranty. But first try another boot to make sure that’ll solve the problem. Let logic prevail. If you try three pairs of boots in the same binding and only one clicks, it’s probably the boot fittings. If all three pairs click, it’s the bindings. As for whether the clicking actually compromises performance, I have no idea. I do know that when I had this behavior occur in one setup years ago, the “pop” on nearly every step was annoying and needed fixing. More, it appeared the micro-movement causing the sound could wear something out over thousands of use cycles.

Readers, your comments on this issue would be greatly appreciated by both myself and the boot makers out there. Fire away.

Original post follows:
I’ve gathered the following over the last year or so from a variety of off-the-record industry insiders as well as my own experience. For reasons that will be obvious as you read, it is time to get this out on the table.

First, a note on language. As far as I and many others in the industry are concerned, the fittings in boots that work with Dynafit type bindings are correctly termed “tech” fittings when not Dynafit branded (or for that matter even when they are branded, as in “Dynafit tech fittings”). “Tech” is a term of art that’s come into common use, not any sort of DIN ISO standard “norm” that’s certified by TUV. At least not yet.

The term “tech” originates from the name of Dynafit binding inventor Fritz Barthel’s company, Low-Tech, and also from various names for Dynafit bindings that have been used over the years, e.g., “Tourlite Tech,” “TLT,” and so forth.

Beyond semantics, this is important. Reason being that despite their simple appearance, tech fittings which perform properly are actually somewhat difficult to make–especially the toe fittings. In a word, they are indeed high-TECH.

Boot-toe tech fittings that perform correctly have to be an exact hardness of steel to not chip or break due to pressure from the binding toe pins and the minimal volume of metal present in the fittings. Thus, tech fittings can’t be super hard steel. Problem is, moderately hard steel could wear quickly, so Dynafit manufactured and branded tech boot toe fittings (and probably the correctly functioning fittings done by other manufacturers, such as those from Black Diamond) are surface hardened in an exact and somewhat proprietary fashion.

Not only that, but while anyone can make a boot fitting that will hold a boot in a tech binding (just drill two holes in a bar of steel), configuring one that does safety release correctly and wears well is another matter entirely. For example, I got my hands on a pair of full carbon (not Dynafit brand) rando race boots the other evening, and it was obvious at first glance that while the tech fittings in the toe would hold you in just fine for rando racing, they would perhaps not function correctly when asked to provide safety release in an unlocked binding. As far as I could tell, the fittings appeared to be nothing more than holes drilled in a bar of steel which was molded into the toe of the boot.

At first glance tech fittings do look simple, but correctly made tech boot-toe fittings have a series of tiny bevels on the outside edge of the socket. These bevels are engineered to provide just the right amount of boot tension and side release elasticity depending on the ramp angle of your boot in the binding, and the direction of forces applied. In other words, with your heel down and latched in alpine mode, when you demand a lateral release, the binding pins climb out of the toe socket on a different bevel than what you’d be in if you were up on a heel elevator, and so forth.

As far as I know the only boot company other than Dynafit who has made boot toe fittings (up to the original date of this post) successfully is Black Diamond. Obviously (as in the race boots I looked at) and not so obviously, other companies try making or jobbing out their own fittings because buying fittings from Dynafit is expensive (some sources told me the fittings add upwards of $100 to the retail cost of a boot). But said again, making them correctly is difficult and requires care, though it’s not rocket science.

Regarding tech fittings, it’s also important to note that how they are installed into the boot is of equal importance to how the fitting is made. If installed defectively or incorrectly, tech fittings can loosen or even pull out of the boot. More, they may be misaligned between toe and heel. Sadly, there is no easy way for the consumer to check the quality of the installation, but pay attention to web reports about boot models cracking near tech fittings and that sort of thing. Also, check the boot construction. I’ve seen boots with tech fittings in such minimal surrounding plastic you could almost be sure they’d easily pull out or loosen during all but the most mellow use.

IMPORTANT: Companies other than BD usually buy their fittings from Dynafit, so don’t get the idea that a bunch of boot makers are going rogue. But the temptation is there since Dynafit charges a premium for their fittings. (Also note there is no reason why the occasional fitting from any company, including Dynafit, would not be defective — nothing is perfect. So if you have problems with your tech boot/binding interface with any brand, always experiment with a different pair of boots and see if you can replicate the problem. If the behavior can’t be replicated with a different pair of boots, perhaps the tech fittings in your boot are the problem.)

All the above is resulting in an interesting and problematic situation. As far as most consumers are concerned, any boot they buy that fits in a tech binding such as Dynafit or Onyx has “Dynafit” fittings. If something doesn’t work regarding the boot/binding interface provided by the fittings, the common reactions are “something is wrong with my binding,” or “the DYNAFIT binding system just doesn’t work for me.” Reality is that such problems with the binding could be caused by a defective tech fitting. Perhaps one made by Dynafit, perhaps someone else — like any manufactured item, tech inserts can be defective. Or, the boot could have an incorrectly made fitting, if someone is not doing his homework or going to the effort of making a fully functional copy.

Because doing so would start a weather event known as an S-storm, other than the case of Black Diamond I’m not going to make any effort whatsoever to try and identify which boots on the market have either Dynafit manufactured or correctly made tech fittings (aside from the obvious fact that Dynafit boots have Dynafit fittings). As far as I can tell, most tech boots DO have either correctly made or Dynafit made fittings (for example, Scarpa’s new Maestrale and Gea boots have “Quick-step” fittings that are obviously the Dynafit made and branded items, and BDs fittings are known to work well). More, identifying the exceptions would be journalistically irresponsible at best, or impossible, as things such as steel hardness and surface hardening would require a lab and a degree in metallurgy to evaluate fairly.

Instead, I’m making a call to the industry for a voluntary standard. I would ask any boot maker to please state if the tech fittings in your boots are either made by Dynafit or are guaranteed tech binding compatible, and that that guarantee means they wear equally as well as Dynafit manufactured fittings, and have the same (or perhaps even better) safety release and touring retention characteristics. In other words, if you’re making your own fittings or buying them from somewhere other than Dynafit they’d better be good, and you’d better guarantee they are good or you will be called out.

I’m sure back in the 1980s Dynafit binding inventor Fritz Barthel never thought his boot/binding interface would result in any sort of common standard, informal or otherwise. But that’s exactly what’s happening. So I’ll even go on record and predict that at some point we’re going to need an industry wide standard for the “tech” boot/binding interface. In the end, that’s the only thing that will eliminate what in my opinion will be a growing problem as more and more boot makers install tech fittings, but choose to make their own instead of buying them from Dynafit.