This year the Dynafit Radical has a small but significant change from previous years’ bindings. The binding includes a tiny spring in the heel assembly in order to provide a small amount of forward pressure.
Forward pressure is one of several features that make traditional alpine ski bindings better than tech bindings, when it comes to going down. Forward pressure actively holds the boot in the binding, while still allowing the ski to flex as well as helping “pre load” the binding toe for elasticity and safety release. Dynafit bindings on the other hand simply allow the boot to slide on the heel pins a small amount in order to allow for ski flex. Unfortunately this only allows the ski to flex a certain amount, and if you boot goes past the limit, you’ll quite possible get a pre-release when your boot heel bangs into the binding heel unit. This has always been one of the drawbacks of tech bindings, and in my opinion causes a fair amount of Dynafit pre-releases.
I’ve been skiing on the new spring-loaded Dynafit binding since December, and have put quite a few days on them. When testing first began, we noticed that the heel piece moves back a small amount every step uphill, due to the spring compressing. My initial thought was that it could be a potential concern for wear and tear on the binding (and of course uses a tiny amount of energy every step). Obvious course of action was to test the binding vigorously, which I’ve been diligently doing through numerous ski trips. A few days ago I took apart the binding to check for possible wear. The binding looked quite good, almost as good as new.
Otherwise, the binding has been performing just as smoothly as past Dynafit Radicals. I ski with fairly stiff skis and I’m a light guy, so I don’t “bottom out” Dynafit bindings in the way that this feature is supposed to prevent, therefore I can’t comment much on its effectiveness. One other minor issue to note: the spring can easily be bottomed out if the binding is adjusted all the way to its shortest length setting (editor’s note, Louie, is that what you mean for sure?). This will not necessarily affect the normal binding functions, however it will make the spring useless, negating this feature of the binding and could be a concern for larger aggressive skiers.