I’ve always been fascinated by surgery. Why not? If during a long athletic career you’re going under the knife more times than you can count, you might as well have some interest in what happens after the cold crisp feel of the IV push — before the OR ceiling fades from view. I wasn’t sure if my ski bindings feel the same way. I asked, they seemed to agree so I went for it, without anesthesia. Amazing how brave injection molded plastic is.
Overheard in orthopaedic operating theater: “We need a bigger hammer.” Step one, pin punch main axle (from smaller end). Click all images to enlarge.
The Dynafit Radical brake weighs 100 grams and is somewhat vestigial if you’re using this grabber for 100% ski touring. Or perhaps more importantly, if you freeride tour without brakes because your skis are too wide or too narrow for your bindings, you know who you are. Oh, and perhaps you simply don’t like fiddling with the brake every time you change modes? Ok, let’s excise it.
After axle is punched part way, pull out with pliers.
Pry out the spring after a small dose of boil temperature water. Beware, when they pop out a small bushing will fly away so cover with a rag or something while you do the deed.
Arms are easily removed from the pedal pad.
Removing arms from the binding base is tougher. Be sure to pour boil temperature water over this area of the base for a moment, you’ll find the arms pull out much easier after you do that.
You’ll probably want to re-insert the axle and anti-rotation catch, but this may be optional. If you decide to do so, be sure the axle gets inserted from the side it was removed, with the knurled-larger end going in last so it doesn’t damage the bore.
The anti rotation will still work if you need it. I’d suggest first trying without. The exposed moldings on the base will probably pick up ice if you’re using heel-flat-on-ski mode. So, bandage the surgery area with a DIY stomp block or other sort of plastic covering.
WARNINGS: This mod is more a proof of concept than anything else. If you do choose to go for it, be advised that re-assembling everything would be extremely difficult. In other words, this may not be a reversible mod. Also, you’ll probably want a stomp block or at least some sort of plastic covering to prevent ice buildup on the exposed moldings. At the least, a layer of duct tape? If you got this far, you’ll figure it out.
Shop for Dynafit Radical 2 ski touring binding.
troubleshooting test that will go away
42 comments
Interesting
In doing so, you are removing the AFD, aren’t you concerned about it?
Pierre can’t you see the air bearing he used to replace the factory AFD??? ?
Rudi, per standard-classic tech binding, the boot “floats” above the ski, no need for an AFD in that situation. See bindings such as Speed Radical. The lack of AFD when there is no brake is one of the Einsteinian things about tech bindings. Lou
I understand that using tech bindings without brakes is considered “hardcore”, and I’m fine with the fact that some folks might like chasing their skis after a release, or when it gets away while they are trying to step into the binding.
The thing that I am struggling to understand is why one would not choose a lighter binding than this to use if lightness was their goal.
The way I see it, going brakeless saves weight, probably improves binding function by reducing friction, reduces risk of losing a ski (if using stout leashes), definitely eliminates problems related to brake malfunction/breakage, costs less… On the other hand, brakes reduce risk of injury from being hit by the ski in a tumbling fall, reduce risk of injury if the ski gets caught or snagged on something, reduce risk if caught in an avalanche…
I’m not pro or anti-brake. I’ve mostly used brakes for the last decade or so, but I’m very tempted to go with leashes for my next setup. I did some searching, but didn’t find a comprehensive discussion of leash versus brake for backcountry. If I missed it, a link would be much appreciated. (And some of you all seem to be going without either brakes or leashes. How does that work?)
See;
I got hit by a windmilling ski in 1973, around the time ski brakes appeared. I converted to brakes, and, haven’t looked back since.
One design issue with the Dynafit binding is the fact that the brake places upward pressure on the thimble inside the heel piece, and, if the brake is not fully depressed when rotating the heel piece excessive wear can result.
In any case; my point was that if you are going for ultra light; this binding was not likely to be your first choice.
One other advantage of leashes – less chance of losing a ski when transitioning and trying to clip in at the top of something steep – especially with the BD “extend-o” leashes..
This reminds me, I really should start testing the BD fused leashes. I’m not 100% comfortable with the concept that they’ll hold together in all releases where they should, and yet break apart when they should.
I understand the concept that the coil absorbs energy and I suppose some long-term redundancy testing is in order (testing on skis which have brakes).
I took a wack in the noggin as well – around the time alpine bindings were transitioning from runaway straps (as we used to call them) to brakes (being a slow adopter).
Cheers,
thom
Lou–this is a sort of random post, but I had not idea where to put these two interesting links. Please move/delete/ignore as appropriate.
I was talking with some folks at a ski shop here in Switzerland, and they mentioned that “most” high-end ski cores are made in Switzerland. I have no idea if this is true, but Switzerland is renowned for “high tech” wood engineering. I found this link:
http://www.bcomp.ch/31-0-bCores.html
Also, as embarrassed as I am to admit this, I bought a Burton “lifestyle” jacket. Yup, it’s true. I think this might be even worse than using frame bindings–can I still post here? While I was browsing the Burton site, I found the history page. You can scroll through their snowboards from year to year, starting in the seventies, up to the present, including their first iterations of split boards. I’m no snowboarder, but I thought the history was cool. I had no idea early snowboards had ropes to hold the tip up. And I had no idea Burton had that kind of background. Cool.
http://ch.burton.com/default/history
Good linkage Bruno, thanks. Lou
Everyone, we’ve had lots of posts over the years that ended up with discussion about leashes (safety straps), below links to a few.
https://www.wildsnow.com/backcountry-skiing-search/?cx=partner-pub-8093284038752434%3Ayxtlw7-4zut&cof=FORID%3A11&ie=ISO-8859-1&q=leashes&sa=SiteSearch
Leashes are not for everyone. Going without brakes is not for everyone. Brakes are not for everyone… I see hundreds of skiers every winter who go without brakes or leashes, they’re generally good skiers who might never have a ski come off during a whole season of skiing. They are trading lack of weight, convenience, and safety from windmilling ski, for the possibility of a runaway ski. My feeling is that good skiers doing 100% backcountry, close enough to trailhead to return on one ski or by walking on packed trails, go ahead and ski without leashes or brakes if they want. Otherwise, brakes or leashes, wise.
+1 Lou, as someone who lost a ski in deep unconsolidated snow far from the TH, and had to spend several hours post holing my way out . I did have brakes, but they apparently didn’t help when the ski shot away in under surface, early season sugar snow (did find it the next summer). Now, for added insurance, I use the ResQski ski finder for deep snow – not perfect I’m sure, but some peace of mind for $100.
@Bruno: Some Swiss national pride seems to have entered into their core discussion – B Comp balsa/flax cores and bulk core materials are made in Switzerland, and quite a few companies use them, but to say “most high end” skis use Swiss cores is a stretch.
“One other advantage of leashes – less chance of losing a ski when transitioning and trying to clip in at the top of something steep – especially with the BD “extend-o” leashes..
This reminds me, I really should start testing the BD fused leashes. ”
IME throwing a ski down on top of a mtn might also seriously freak out your guide if he doesn’t realize you are clipped to the ski with BD leashes 🙂
My experience with the fused B&D leashes is that they will break away in a violent fall and I can easily break them by kicking hard, so I am pretty confident that they will either break in an an avalanche or stretch so much that they become a non-factor. Are they 100% reliable to stay intact in a violent crash? Absolutely not. They work really well in a moderate fall, though, and provide nice piece of mind when removing skis in steep consequential terrain. I’ve used both the provided zip ties and some loosely calibrated cord (window shade cord) fuses. I generally am in the prefer-fused leashes-over-brakes camp in deeper, softer snow and like brakes on hard snow.
Hi Lou,
sorry for hijacking this topic. I have a question considering developing play on the heel unit of a vetical st binding. I noticed the pins of my heel unit have developed up-down play. The heel unit is stable, just the pins are moving. Do you know anything on this problem?
Thanks,
Vincent
I love B&D leashes (not BD, Black Diamond also does make leashes but assume everyone above means B&D). Released and took a sliding fall with them this morning and they held the ski perfectly (meaning they did not break under the force of a “typical” fall). I don’t like the idea of adding zip ties into the equation because I find that different zip ties do not always stay zipped on.
Not using brakes or leashes seems like Russian Roulette to me. It may take a few seasons, but a ski is going to get away sooner or later. But, I have had a ski take a huge solo ride with Dyna brakes too, so I only use leashes now.
I too prefer B&D leashes, mostly to avoid loss when getting into the binding where an escaping ski would be a big problem. A release while skiing hardly happens for me. I like their stretchy goodness too, which permits reskinning or field-waxing without detaching the leash. B&D supplys breakable plastic links in two rated strengths.
Another option for breakable links is split rings, as used for keys etc. Test difference sizes to failure and use your favorite.
Split rings? How exactly would they work?
“Split rings? How exactly would they work?”
They would deform and pull open when under enough tension, as for example during an avalanche. I suppose a split ring could be used at either end of the leash, at the skier’s convenience.
Interesting idea; thanks Jim.
I’ve tried split rings, they’re pretty weak unless you use a big one, then they’re unwieldy and large, in my experience anyway. A much better method is just take some paracord and make a loop, or a double loop, or a triple loop. Use thinner cord if you need it weaker. Question is, how many pounds (newtons would be more accurate statement) of force should we be building these things for?
Bill says his ski leash fuse links break at 40 or 60 pounds. Pretty easy to static measure a load that small.
http://www.bndskigear.com/skileash.html
Some of you guys good with math and physics. Let’s say you’re skiing at 20 mph and you fall, and your ski comes of, so your ski is moving at 20 mph and your body stops, then the ski leash engages and stops the ski. Can anyone calculate the force, in newtons and pounds, that would be exerted on the ski leash when it decelerates the ski?
https://www.easycalculation.com/physics/classical-physics/newtons-second-law.php
https://en.wikipedia.org/wiki/Parachute_cord
Mil-spec Type 1 paracord is rated at 95 pounds with 30% elongation. A loop with a knot is going to be less, and might even be just the right strength for a backcountry ski leash fuse link. It’s basically what I’ve always used. The core can be removed, reducing the strength even more.
Only problem with this is that most paracord I’ve bought over the years is clearly junk, not mil-spec.
Lou
It’s complicated, Lou. The skier’s boot doesn’t stop in an instant (maybe not for a while, depending on the fall), and the ski is decelerating too as it leaves the boot and stretches the leash out to six feet. A heavier ski/binding combo would call for a stronger link.
Just guessing, but I think Bill has got it right with his forty and sixty pound breakable links. It’s better to err on the low side and to be more likely to lose the ski in an avalanche. That’s another reason not to crank the binding release up to the max.
Gotta go. More new snow! The joy is cranked up to the max!
I’ll bet a knotted loop of mil-spec type one would break at 70 or 80 pounds. Time to test. Have fun skiing. Snowing here as well. Been doing quite a bit of backend work on the website, but will be getting out! Lou
My theoretical understanding is that a loop tied with a double fisherman’s knot will be stronger than the quoted strength of a single strand of cord….
http://efclimbers.net/wp-content/uploads/2013/02/Knot-and-cord-strength.pdf
I use cord as a leash on my bindings and I’d be really interested to see the results of any testing that you do.
What!?
That’s pretty interesting.
I guess we should tie it with a single fisherman or water knot then…
Or a single strand with overhand loop at each end.
‘best, Lou
I ordered up some “Type 1” pcord, 95 lb breaking strength. We’ll see how it goes. Lou
This is all rather interesting…
The energy of a moving body must be countered by a force, applied over a distance (i.e., work), to have the body come to a stop.
So, for example, a 200 lb man falling four feet straight down would have a dynamic energy of 200 x 4 = 800 lb-ft (E = mgh); this must be countered by work for him to stop. The work needed to stop = the impact force x stopping distance = F x sd. So, equating work and energy, the impact force, F = E / sd(stopping distance).
So, if the guy fell into powder and moved two feet before stopping, the impact force would be 800 lb-ft / 2 ft = 400 lbs (about 1800 newtons). On the other hand, if he fell on hardpack and only moved 1 inch before stopping, the impact force would be 800 lb-ft / .083 ft = 9639 lbs! (No wonder my shoulder dislocated when I went straight down on that ice – ouch!)
I suspect how all this translates to break strength of powder leashes and avalanches is another (more complex) problem, but it does illustrate why ropes have stretch.
“But, I have had a ski take a huge solo ride with Dyna brakes too, so I only use leashes now.”
yeah I have seen dynafit bindings with brakes deployed go a very long way both on piste at a ski area Blue run and off piste in the alpine
It is possible to replace dynafit brake arms with arms from the salomon guardian which deploy properly but due to the added leverage of the Salomon arms the return springs of dynafit brakes won’t keep the ski off the hard piste which helps slow down the ski but I think they will work in soft snow …haven’t tried that part
In my opinion, trying to predict load on a leash beyond a rough order of magnitude is a pretty futile task given the number of broad assumptions required. I think a more logical way to approach sizing a breakaway is to estimate what your body parts can tolerate when tension is applied to the foot in an arbitrary direction. At the end of the day, that’s all that matters anyhow. Having more than ~50lb tugging on my foot in some random direction sounds like it would be as much as I could tolerate.
That said, the best leash would be one that has a fairly low breaking strength, but can stretch significantly before reaching that load (giving the ski the best chance of slowing down rather than breaking the leash immediately).
I think the main point of having a fuse in the leash is so that the skis won’t act as an anchor in case of an avalanche. But I agree that trying to figure out exactly what the load is at which the fuse should blow is a problem.
I was recently considering getting some brakeless bindings, but I decided to go with brakes for the new setup and try leashes on some older skis. I’m hoping the new brakes perform better than earlier ones.
on the note of skiing the radical 2.0 without brake, I am considering the surgery for not weight reasons… the spring that actuates the lever snapped on me and now the lever is stuck straight up, making click in a hefty 2 man operation and compromising the retention greatly (I discovered this when clicking in on the summit of baker sunday)… I’ve spoken with dynafit and have a replacement on the way, but I don’t want to be stuck on a summit again with unusable gear, so I’m considering removing them both. dynafit’s rep “does not recommend” this mod no matter how many different ways I asked the question for undisclosed “safety compromise”.
What I’m wondering is if you’ve played around with the brakeless radical 2.0 and whether the removal really will compromise the anti-rotation or retention power of the heel turret.
If you could expand a bit on how the anti-rotation lever and the tongue of the turret interface without the spring included, I’d much appreciate it!
Thanks, and Mod on!
Hi Matt, while most reps in my experience are really not all that expert on ski binding mechanics (their job is to sell bindings, not repair them), and playing the “safety compromise” card is always an amusing out, I’d agree with the guy you spoke with, that this is too untested of a mod to be mainstream. I don’t have the modified binding handy, and don’t recall exact anti-rotation details, but I do remember it was possible to reconfigure so it worked. ‘best, Lou
Thanks for the speedy reply Lou! I didnt get my replacement heelplate in time to get out tomorrow so I did the brake removal and whipped up a ice-space-fillerator/stomp pad. should allow for solid contact in touring mode but leaves the classic tech float gap while pins are engaged. See file link below
https://drive.google.com/open?id=0B5kQvG_PdzqKdkhtNldVZ19lQnc
Will report on performance after testing on Ellinor’s North side tomorrow.
I think I am gonna do this on my Dfit rad 2.0 binders with the 120 brakes. Ended up not mounting them last year and would like to use them some how.
I did this mod to my clamps and it was easy peasy Did not use any hot water and the brakes pulled right out. The holes will get egged out a bit.
I also put the spindle and anti rotation retainer back in, used a generous spooge of black silicone to hold it down since the brake pad and springs are no longer in play.
Thinking about trimming the base back a bit but the adjustment track runs down the the sides pretty far so cutting back the excess may be problematic.
I have the Dynafit Radical ST2.0 currently mounted on skis that are 95 width, I would like to move the bindings to 107 width skis. Has anyone succesfully replaced the ski brakes with a wider version?, if so what ski brake did you use.
Thanks, Chris
Hello all: I recently bought a set of these with the widest brakes possible, because all others were out of stock. I am happy enough to switch to leashes having used them in my youth and on three pin gear. I see that since the brake removal might be a one way path, I was wondering what you think of just grinding off the brakes flush with the binding base? Is that trick heel pad considered a liability? It looks to me (a novice) that it would preserve the anti rotation function and protect it from ice buildup. I am not too concerned with the weight penalty since I need to lose 10 pounds before counting grams.
Raoul, I think you could cut the brake arms off. Experiment with how much you’ll need to leave, and don’t create any sharp edges! Lou
Thanks! I was thinking flush so no grabbers remain but they also retract so I’ll have to account for that too.
I’m considering doing this “brake-ectomy” this afternoon. Just curious if anyone who has done it has noticed any issues / reasons not to do it after using them for a while?
And, is it possible to remove the brake while the binding is on the ski, or will I need to remove and re-mount?
Thanks
So I decided to cut the brakes off, after marking where the shafts would sit with the heel pad down and locked. They retract about 1/4 inch in “go mode”
I used a cordless high speed grinder(bicycle thief’s tool) with the thinnest wheel available. The brake shafts tried to heat up so I just wrapped the plastic brackets in a wet cloth. It took a few seconds, easy! The heel plate and anti rotation lock work the same as factory no issues so far. I had to put the leashes on the heel piece and clip them to my boot buckle handle but it just adds a few seconds to stepping in, and you have to watch the ski doesn’t run off before you click in. Happy with the result- thanks for the encouragement!
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