Lou Dawson's Backcountry Skiing Blog & Website -- Legacy Pages

Frequently Asked Questions (FAQ), tricks, and tips
Dynafit Tri-Step randonnee "AT" ski bindings

By Louis Dawson

NOTE: On March 19, 2003, Dynafit announced that they were bagging the inherently defective Tri-Step ski binding. The binding is to be discontinued and replaced with the "Comfort," which will use a toe mechanism similar to the tried and true TLT (see general Dynafit FAQ for TLT info), combined with a re-badged Tri-Step heel. See this edited press release for more details.

What is this FAQ about?

All Dynafit models function nearly the the same way and are very similar. For general information about the bindings, see this FAQ. For information specific to the Tri-Step, you're in the right place.

Dynafit makes a number of models of backcountry ski bindings, the Tourlite Tech (TLT), Comfort, ST and FT are examples. In 2001/2003 they made and sold a model called the Tri-Step.

2002/2003 Tri-Step. It looks similar to the previous freshman offering, but is significantly re-engineered. (Heel has logo lettering, which somehow was blocked by a reflection in the photograph.)

What are the changes for the Tri-Step Binding, winter 2002/2003?
In October 2002 I received a 02/03 Tri-Step binding on a demo board, and subsequently received several other pairs of bindings for evaluation, mounted them on skis, and tested them for several months. I also receive dozens of emails about people's experiences with both the TLT and Tri-Step, and incorporate those emails into these FAQs. While I can't name all those individuals, I thank them.

Dynafit Tri-Step binding changes for winter 2002/2003

• New model Tri-Step, front view. The yellow bar indicates full lock in touring mode, eliminating any doubt on the part of the user.

  Yellow indicator graphic shows when the binding toepiece tab is locked in tour mode.
• Toepiece is redesigned, with metal piece to prevent unintended release in tour mode. This is the big one, as last winter's "fixes" from Life-Link and Dynafit were not the kind of engineering excellence we've come to expect from Dynafit.
• Locking to tour mode may be more positive.
• Heel adjustment screw changed to posi-drive and slot-head screw instead of allen head, allowing you to carry one less tool in your repair kit.
• Hidden metal plate in heelpiece that contacts ski top is now clearanced so it has less friction during for/aft adjustment.
• Plastic toe housing is beefed with internal structure. (This and new toe lever add .7 ounce to weight of binding.)
• Screw hole in toe lever is clearanced to make mounting easier.
• Binding now sold with or without brakes, if bought with brakes they are attached to binding (installing brakes at home is a moderate hassle).
• Overall weight increase of approximately 1 ounce per binding (Tri-Step is about 28% heavier than the TLT binding).

These changes solved most of the issues this binding had when first released. Ongoing issues are: ice formation within plastic housing, release of binding in touring mode when a foreign object such as an ice chunk catches between boot toe and binding lever, difficulty of pulling touring lock tab up to total lock position, continued problems with larger skiers inadvertently ejecting from the binding while in touring mode, and more.

Overhead view of the last and best production Tri-Step toe. The curved metal lever is designed to eliminate the hazard of your boot bumping the binding and unlatching it from your boot.

What's the main difference between the Dynafit Tri-Step and earlier models?
In most way the the Tri-Step works the same way as any other Dynafit binding, and is nearly the same mechanically. Among other differences, it has a cowling over the toe for a more streamlined appearance, and has a wider range of adjustment for different boot sizes. The Tri-Step raises your boot higher off the ski than the TLT. Also, the pins on the Tri-Step that insert into your boot heel are longer than those of the TLT. This may result in better elasticity for less possibility of prerelease.

The Tri-Step is 28% heavier than the TLT and has a heel post that may be easier to rotate with your ski pole.

It's said that the Tri-Step has a configuration that makes it easier to snap your boot toe into the binding, but in my tests I have not found this to be so.

When in touring mode, I walk out of or pop out of the Tri-Step binding toe, what's the deal?

TRI-STEP BINDING Toe Piece Directions

To Lock -- Pull Toe Lever up until yellow "locked" stripe is fully showing. If you cannot pull the lever far enough up to see all of the yellow stripe, hook the shaft of your ski pole under the lever and pull up with both hands on ski pole.

For those who have not used the Dynafit bindings: To enter the binding, you place the toe of your boot on the toepiece with the holes in the boot lined up with the small pins on the "wings." You then press down, triggering a set of small springs that close the wings on to your boot, with the pins in the holes. For downhill mode, you then weight your heel and drive your boot down on to the heel latch pins. For touring mode, you leave your heel unlatched, but you must reach down and pull up the small gray plastic tab on the toe, which locks out the release so you won't pop out while touring. If you try to tour without the toe "locked," you'll soon release out of the binding when you try to walk. If this lever gets accidentally pressed down while you're touring, you will walk out of the binding.

The above causes a nomenclature problem. When you are reading this FAQ, be clear that that the words "latched" and "locked," for example, could mean simply latching the touring lock lever, or actually removing or attaching the binding to your boot. I'll try to be as clear about this as possible, and attempt to use the words "locked" and "unlocked" to exclusively mean the use of the touring lock lever, as is done in the illustration to the right. Please email me if you get confused, and I'll try to improve my prose.

When the Tri-Step binding was first released in 2001, people immediately reported they were walking out while touring, even when careful with the touring lock mechanism. This led me to believe that the 2001 Tri-Step binding needed more evaluation and testing, and possibly improvement, before I would recommend it. As it turned out, early bindings during the 2001/2002 season were indeed shipped with a design flaw which did certainly cause skiers to pop out while in touring mode. For the record this debacle is explained more at the end of this FAQ. This specific problem appears to be 100% fixed with the new model release for winter 2002/2003.

Thus, if you still walk out of the latest model 2001/2002 binding while in touring mode DO NOT BLAME THE BINDING FIRST. Instead, read on:

I believe I use the Tri-Step binding correctly, and I still pop out while touring, ideas?
I have torture tested the Tri-Step and had no problems with inadvertent release while touring. Several other experienced ski alpinists also report using the Tri-Step and having no problems with this. Nonetheless, I do receive reports of this problem and my conclusion is that it is a true problem with the Tri-Step, especially for larger skiers, and is probably why it was discontinued. Nonetheless, In most cases something is awry with your use patterns if you consistently release from the Tri-Step while touring. Things to check:

• Before you step into the binding, clean any packed ice and snow out from under the visible toe-unit springs. Junk packed in the deep pocket under the springs will keep the binding from closing properly. The plastic cowling on the Tri-Step exacerbates this problem, and is one reason I prefer the TLT.
• The sockets in your boot must be clean, and the binding fully closed on your boot after you step in. It's easy to overlook this, as you can walk away with the binding partly closed, with the pins riding on ice or dirt packed in the boot sockets. Carry a 16d nail for cleaning out the sockets, or use the awl on your multi-tool.
• For walking/touring mode, the touring lock lever (the gray plastic tab up front) must be pulled up firmly after you're in the binding. Make sure you can see the yellow lock indicator before you start walking. It may take quite a bit of force to pull the lock tab up to the point where you see all of the yellow bar (see more about this above and below). If in doubt, try pulling the lever up by placing a ski pole crosswise underneath it and yarding up on the pole with both hands and significant force.
• Once the binding is closed and locked, swing your foot and ski a few times to work the pivots and make sure they are seated. Stomp and torque your foot to the side and make sure it feels locked.
• Bench testing shows that the touring lock lever (the gray plastic tab up front) may be ultra-sensitive to being pressed downward and thus being switched from the locked mode to alpine mode. One of my test bindings easily switched from tour lock to alpine mode by gently pressing down with a finger. Using a scale, I measured that it only took 6 pounds of force to switch it. What's more, compared to the TLT binding it is in a position that is much easier to hit downward with a ski or other object. Thus, it could easily be switched to alpine mode if you hit it with your other ski during a kick turn, set your pack on it while taking a break, or doing something else that presses down on it.
• Remember your technique. Avoid wild moves on steep terrain. Don't jam your boot forward to the point where the toe-box impacts the binding. Dynafit bindings are incredible, and used by hundreds of thousands of ski mountaineers. But this might not be the best binding for inexperienced ski mountaineers, as it certainly requires more care and feeding than bindings such as the Fritschi Diamir.
• The binding may release if you get a chuck of ice or hard snow packed in front of your boot toe, and jam your boot forward. This can be demonstrated on the bench by placing a soft object between the boot toe and touring lever, then raising the boot heel. Try using a rubber eraser for this experiment. Reports of touring release while breaking trail in deep snow, or bushwhacking, might be the result of this.
• Some boots may not have a thick enough sole under the toe to push down on the toe-unit and cause the binding to snap closed. If you use the Laser boot, be extra sure to check this. Fix by building a small pad of duct tape on the binding so the boot has something to press on.
• Users frustrated by "surprise release" have told me they suspect their boots might be defective -- perhaps with the wrong dimensions, or something like that. The Dynafit fitting molded in the boot is a solid steel block with the sockets machined at each end. Thus, the sockets are always the correct distance apart. Could the fitting be molded in crooked? Perhaps, but I don't see how this would cause release in touring mode.
• While touring, glance down at your bindings occasionally and make sure your touring lock lever is still up in the locked position. I've stepped on mine a few times during a thrash or while taking photographs, and ended up walking out of the binding.
• All new users should torture test their bindings at home, on carpet. Practice getting in and out. Practice pulling up the touring lock lever. Practice rotating the heel lift. Try dropping to your knees and observe how doing so may pull your boot out of the binding.
• If you put in a few days on the binding, do all the above, and are still frustrated by touring release, it could be wise to cut bait and use a simpler binding.
• If all the above fails, perhaps you have defective bindings or boots. The only way to figure that out is to try another pair -- a good reason to buy your bindings from a dealership committed to customer service, ditto for boots.

More about making sure the Tri-Step is locked into touring mode
In some cases, it is difficult if not impossible to pull the Tri-Step touring lock tab up to the point where it makes a satisfying click, and shows all of the yellow bar painted on the front of the toe lever. I had this problem with a recent pair of bindings. After many hours on the bench, including reverse engineering almost the whole toe piece, I found that a small metal part appeared to be slightly too large, and blocked a pin from sliding crosswise along a slot. See illustrations below:

Above is a view of the binding toe without cowling, and with some parts removed or moved aside for easy viewing. The metal part that's too high is of a much softer metal than the pin. Thus, if you have a problem with your bindings being hard to lock, try this: Place on a workbench, put a boot in the binding, then lock/unlock touring mode several hundred times. This will cause the hardened steel pin to ease a land in the metal that blocks its path. You must do this with the boot in the binding, as they usually work fine without the boot (due to a change of internal angle in the mechanism caused by the boot between the pins of the binding wings).

After taking the binding almost completely apart (more than shown here), I was able to file down the dark metal a small amount, perhaps 1/64 inch. Doing so made a huge difference. The binding I filed now easily locks into touring mode, shows all of the yellow bar, and takes quite a bit of pressure to force down out of touring mode (as it should). I do not recommend doing this modification as it involves pressing a pin out of the binding, and removing a precise amount of metal. Instead, if you have problems with your bindings locking, place boot in binding and go from lock to unlock several hundred times. Do so with a good amount of force each time. This should allow the hardened steel pin to wear down the softer metal under it. Trying to fix your binding this way won't void the warranty, as taking it apart and modifying it surely would <grin>. Several users have also told me that Life-Link has made this mod to bindings they returned because of problems with locking. So if you can't get the binding to lock properly, keep working with Life-Link or a dealer and don't give up hope.

It's said the Tri-Step is easier to click into, is it? Why do they claim this?
The boot pins on the Tri-Step binding toe unit are about 3/16 inch closer together than the TLT (when open and ready to receive boot). Also, the trigger under the toe of the boot, which when pressed causes the wings to close on your boot, is more sensitive on the Tri-Step than on the TLT. It's also said that the heelpiece is made in such a way that one can use it to align their boot for entry into the binding.

These factors might make the Tri-Step slightly easier to click into, but in my real-world testing I noticed little, if any, difference in this. As with the TLT binding, the trick is to get one pin in a boot socket by slightly tilting your boot sideways, then step down at the toe to click in, while keeping the boot aligned to the sockets. Reality is that doing this can sometimes be difficult. Practice at home if you're new to the binding. And remember that the boot sockets must be clean for positive engagement with the toe unit pins. Make a pin-hole cleaning tool out of a 16d nail.

I heard some Dynafit Tri-Step users were having problems with the front part of the binding icing up, and that the cowling on the front prevented you from removing the ice. Has this been a problem? Is it fixed with the 2002/2003 model? There are no changes I know of in the 2002/2003 model that would make any difference with icing issues. While such ice is not a problem for most people, I have heard of this happening so it's something to consider. After all, many of us who use the TLT much have had ice form in the pocket under the toe wings, and had to remove the ice to get the binding to work. Thus, this could also happen with the Tri-Step. Again, more testing and comments from users will make it clear what the situation is with the icing question. The guy/engineer side of me likes the TLT without the plastic. I spend a lot of time cutting extra junk off my packs, automobiles, and clothing -- are my bindings next? (Actually, the cowling is part of the binding's mechanical system, so it probably has to stay).

Does the Tri-Step give more reliability for aggressive skiing?
It's been obvious for some time that the TLT binding, when used with a severely flexed and soft ski, may not allow enough for/aft movement of the binding in relation to the boot. While this is not a problem in average backcountry skiing, it's well known that if you jam a soft ski into a bump trough or other declivity, your boot may pop out of the binding, vertically at the heel. Indeed, what may cause this could be demonstrated in the workshop by aggressively flexing a soft ski with attached boot. Do so, and you'll notice how the boot heel can jam against the binding. Conversely, if a soft ski was heavily "cambered" or reverse flexed, it could pull the pins out of the boot heel. I've had that happen when a bunch of slush piled up on my skis, and I went for a wild jump-turn.

The latter occurrence is easy to replicate indoors. Latch a boot into the binding, flip the ski upside down, and suspend it between two solid supports at tip and tail. While pulling the boot heel down towards the floor, aggressively press down on the center of the ski to induce exaggerated camber. You'll be surprised how easily the boot pops out when the pins pull out of the heel fitting. The longer pins of the Tri-Step help with this problem, as they allow extra distance before they pull out of the boot fitting. With either the TLT or Tri-Step, be extra sure the specified space between boot heel and binding is no larger than spec. With either binding, my opinion is that the pins should be longer, with a deeper pocket in the boot heel. Just a few millimeters would make a huge difference.

Said again: The Tri-Step and Comfort binding's heel pins are several millimeters longer than those of the TLT, and the Tri-Step heel lacks the mysterious bump that reduced clearance even more with the TLT. Factory spec for heel clearance on the TLT is 4mm, while it's 6mm with the Tri-Step, a significant 50% increase! Perhaps this will eliminate tendency for "pop out," in alpine mode, or make is so rare it's a non-issue, but when testing in the shop, I found the de-camber type of pre-release is still remarkably easy to replicate with the Tri-Step. In the field, I found the longer pins made a significant difference, and have tested the binding with aggressive skiing in double black diamond terrain, with good results.

I tested the effectiveness of the longer pins by removing them from the Tri-Step binding and swapping them into a pair of TLT heels. This resulted in a VAST improvement in the performance of the TLT when using them for things like aggressive bump skiing or doing jump turns in heavy slush. Thus, I can say with confidence that the Tri-Step should be even less prone than the TLT to any sort of prerelease If you care to try swapping the longer pins into the TLT, remember that doing so throws off the DIN release setting numbers, and you'll have to set your binding tension by trial and feel (don't we all do this anyway?

Do the Dynafit TLT and Tri-Step bindings use the same mounting screw hole pattern?
Yes. What's more, the Tri-Step comes with the screws inserted in the correct holes, a nice touch that eliminates confusion about where the different shaped screws are supposed to be used. With this in mind, the Dynafit demo-rental plate would probably work with the Tri-Step. This plate gives a huge range of boot length adjustment, and more rise.

Is there anything else I should add to my repair kit specific to the Dynafit bindings?
Please see the TLT and generic Dynafit binding FAQ.

Above view of binding with heel release mechanism removed for removal and attachment of brake. The new Tri-Step brake was designed to be field removable with this little tool, but it came off too easily and must be installed with an extra part that obviates the convenience of removal and replacement in the field. Expect this to be fixed in the future. The drawing I scanned came with a set of brakes I received in 2001.

I've heard that the Tri-Step ski brakes were designed to be field removable and field attachable, but now they come with an extra part that makes them permanent, what's the deal?

Indeed, the Tri-Step brake was originally designed to ingeniously slip on to the heel post, then lock into two notches on the heel post. You used a small tool for removal (illustrated to the right). Problem is, the clipping action of the brake is weak, and it popped off too easily in the field.

Dynafit's solution to this is a small metal clip that locks the brake on the heel unit, but sadly obviates the field-removable feature. In other words, you must take the binding apart to attach and remove the brake.

I suspect this will be remedied in future versions of the brake, and look forward to brakes that can be attached and removed in the field.

Sadly, the new 2002/2003 model continues this uncharacteristic (for Dynafit) state of affairs.

Seems like my next homebrew mod will be to get this field-removable brake working? Indeed, it appears there are several easy ways to secure the brake without using the afterthought clip, perhaps by drilling a small hole and inserting a clevis pin or something of that nature.

Stay tuned....

My ski brakes jam under my boot sole lugs, should I be concerned?
Yes, this can compromise your safety release! See the general Dynafit FAQ for info, as this can happen with either model.

Be super careful with ski brakes on any alpine tour binding -- all the ones I've seen are quirky.

For history's sake, what was the deal with the (in)famous toe plugs on the first release of this binding in 2001?

BELOW OFFERED FOR THE HISTORICAL RECORD. THIS SHOWS THE TRI-STEP BINDING FROM 2001/2002, WHICH REQUIRED THE RETROFIT "PLUG" IN THE TOEPIECE. I truly believe I'm doing Dynafit a favor by saying that in my opinion this "plug fix" is somewhat unacceptable (depends on exact use), more, the original production Tri-Step, without the modified toe plug, is utterly worthless because of the boot ejection problem. So be careful what you buy on the used market.
Binding with old plug, note how boot impacts plug. This causes instant ejection from the binding.	Tri-Step toe plug mod just before installation. Make sure your bindings have this style plug.	Binding with plug, boot presses down in a way that does not cause ejection.

Even after installing the plugs, some users still reported that they walked out of the binding while touring. This may prove that the binding has an inherent flaw and is perhaps why it was discontinued. I have two theories about this: One is that some boots have toe-box shaped in such a way that it impacted the front of the binding and still caused ejection. Another theory was that snow or ice would build up on the binding or boot, then cause the boot toe-box to push down the lever and cause ejection. Whatever the case, this episode is now history. At this time, make sure you are using the latest model of the binding and if you find this binding on the used market, make sure it is the version with the yellow stripe on the toe lever (see above). I do not recommend using the first 2001/2002 offering. If in doubt, use the photos in this article to ID your bindings. The 2002/2003 model you want has a beefy curved metal toe lever, and a yellow stripe on the front that shows when it is locked in tour mode.

(Note: Writers, magazines, etc., using this FAQ for reference, please give credit where credit is due.)