NOTE: The following information is retained for historical continuity. The “anti rotation pin” system detailed below was a design and engineering failure and was subsequently upgraded to an entirely different solution.
As many of you have heard by now, Dynafit has issued a writ of much importance regarding a part of the Radical series bindings. The part is the small, brass pin that keeps the heelpiece from rotating counter-clockwise when in tour mode (which is rare but can happen on occasion as Dynafit binding users can attest).
Under purportedly rare conditions during use, the pin can be subjected to excessive forces that aren’t necessarily damaging to the binding or able to cause the binding to malfunction, but which nonetheless have inspired Dynafit to announce that all Radical bindings would benefit from a retrofit to a slightly modified heelpiece pin.
Original Dynafit Radical heelpiece pin on left, replacement pin on right (which is inserted into the aluminum heel spindle with small end first. Penny for scale.
I personally switched out ten pins today in the Radical FT, ST, and Speed. Done with care, all went smoothly and the procedure took very little time per pair of bindings. Owners of Radical series bindings can go to their local Dynafit dealers and have this procedure performed, or if needed, can contact Dynafit customer service directly for a return authorization when having a dealer perform the service isn’t possible for various reasons.
Having said all this, my impression is that retrofitting the brass pins isn’t ultimately essential, but a way for Dynafit to get ahead of the curve regarding that very rare incidence of the pin being compromised in some way. Put a different way, a set of bindings with the original pins would likely work flawlessly for millions of backcountry vertical feet. The engineers are simply being proactive.
If you do choose to do the swap yourself, know that the crux is actually not the swap, but removing and replacing the rear spring barrel (AKA cap) without stripping its plastic threads. A couple of tricks for that. First, make sure the thimble bushing and associated spring are completely inserted before you try and thread the cap. To test for this, while pressing spring in by hand and rotating binding housing, you should be able to feel the spring move in and out as the housing rotates over the binding spindle lobes (binding must be rotated in the alpine mode direction, pins forward, to feel this). Second, once you do have the barrel ready to screw in, check from different angles to be sure you’re starting it straight, and be gentle as if aligned it should be easy to make the first few turns before the barrel really starts compressing the spring.
In terms of the pin, main thing is to keep your fingers over it while you pull off the housing, so it doesn’t fly away. Pull the rest of the way out with your fingers or needle nose pliers, insert new pin per Dynafit’s instructions (it goes in small end first), then hold it in with your finger or a small tool as you slip the housing down over it. Before replacing housing, look at it from the bottom and remember where the small slot for the pin is, so you can orient it correctly as you slip it down over the spindle.
Internal spindle with old style pin.
So if you were wondering about the little brass pins in your Dynafit Radical bindings and the recommended technical upgrade which is not a re**** — well, this should get you up to speed.
