Tech Bindings/Boots for XC

[anrothar]

I weigh around 210 at 6'3" and am on the 205 Eon. I've been using them with NNNBC Magnums, modified to prevent freezing up, the entire time, but am about to switch them over to AT toe pieces and chopped at boots, which is what I have on the Pellestovas, Sierras and SBounds. At size 49, I've found the sturdeist Rossignol and Alpina boots to be too easily twisted in the forefoot in comparison. The AT toepiece setup, with properly cut down boots, weighs less, turns infinitely better, skates better and k & g's about as well.

Mind going into some detail (picture perhaps) outlining this. Never heard of this before and it sound intriguing.

Singletrack:

They do well as long as it isn't too twisty and doesn't have too many steep climbs where the length is prohibitive. The Sierras are much, much better for singletrack. In fact, I would say they're almost the ideal singletrack ski.

Interested in where the Sierra falls in between this and the S98. I find the S98 to be a very good ST ski, mainly due to it's turn and immense grip. The Eon is OK, it just can't get up steep hills as well.

Hopefully my parsing of the quoted text worked....

Luc Mehl has been using the AT toepiece setup far longer than I and explains the pros/cons pretty well.

http://thingstolucat.com/ski-touring-equipment-guide/

The only thing I do different is to take a hole saw to either side of the boots where the bellows on a plastic tele boot would be. I also leave the cuff attached, but trim it down as much as possible. After gluing in a gaiter, this allows them to flex in the forefoot like a stiff nnnbc boot, but with most of the torsional stability of an in tact plastic boot. Combined with the completely free pivot, they tour on mellow terrain exceptionally and skate ski as well as any high end skate ski boot. I can even skate the SBound 98's comfortably with this setup if the snow is warm enough or firm enough. I mount the bindings with pivot a hair behind the balance point so that the skis slowly level themselves out when picked up. I'll attach a photo of what my old Scarpa Magics look like modded this way. Currently on Dynafit Mercury.

Regarding singletrack, I find the S98 to be a little too wide if it's been a while since the last snow on a high bike traffic trail. The Sierra behaves nicely in a slightly bowled out tread that often occurs in those situations.

[HBS]

Luc Mehl has been using the AT toepiece setup far longer than I and explains the pros/cons pretty well.

http://thingstolucat.com/ski-touring-equipment-guide/

The only thing I do different is to take a hole saw to either side of the boots where the bellows on a plastic tele boot would be. I also leave the cuff attached, but trim it down as much as possible. After gluing in a gaiter, this allows them to flex in the forefoot like a stiff nnnbc boot, but with most of the torsional stability of an in tact plastic boot. Combined with the completely free pivot, they tour on mellow terrain exceptionally and skate ski as well as any high end skate ski boot. I can even skate the SBound 98's comfortably with this setup if the snow is warm enough or firm enough. I mount the bindings with pivot a hair behind the balance point so that the skis slowly level themselves out when picked up. I'll attach a photo of what my old Scarpa Magics look like modded this way. Currently on Dynafit Mercury.

What's the benefit of that setup over something like a Scarpa T4 + Voile cable binding? Less weight?

[anrothar]

Luc Mehl has been using the AT toepiece setup far longer than I and explains the pros/cons pretty well.

http://thingstolucat.com/ski-touring-equipment-guide/

The only thing I do different is to take a hole saw to either side of the boots where the bellows on a plastic tele boot would be. I also leave the cuff attached, but trim it down as much as possible. After gluing in a gaiter, this allows them to flex in the forefoot like a stiff nnnbc boot, but with most of the torsional stability of an in tact plastic boot. Combined with the completely free pivot, they tour on mellow terrain exceptionally and skate ski as well as any high end skate ski boot. I can even skate the SBound 98's comfortably with this setup if the snow is warm enough or firm enough. I mount the bindings with pivot a hair behind the balance point so that the skis slowly level themselves out when picked up. I'll attach a photo of what my old Scarpa Magics look like modded this way. Currently on Dynafit Mercury.

What's the benefit of that setup over something like a Scarpa T4 + Voile cable binding? Less weight?

Significantly less weight, more durable(not that the T4 + 3pin cable binding isn't durable) and the free pivot close to the toes makes it tour much more efficiently on the flats and climbs.

I go into it in much more detail in the following two threads:

viewtopic.php?f=1&t=1407&p=17215#p17215

viewtopic.php?f=1&t=76&start=490

[HBS]

Significantly less weight, more durable(not that the T4 + 3pin cable binding isn't durable) and the free pivot close to the toes makes it tour much more efficiently on the flats and climbs.

I go into it in much more detail in the following two threads:

viewtopic.php?f=1&t=1407&p=17215#p17215

viewtopic.php?f=1&t=76&start=490

Cool - thanks for the links.

I have been putting together an AT setup this winter, almost ready to hit the slopes. Maybe something to think about in the future.

Did you find you had to size the boot up for K+G comfort?

How is K+G without a bumper at the front of the ski? Seems like it would feel weird to be able to over rotate.

[MikeK]

Split this from the Eon Review - don't want to water down ski reviews with other relevant conversation.

[MikeK]

How is K+G without a bumper at the front of the ski? Seems like it would feel weird to be able to over rotate.

This has been a frequent topic of contention here, and I've never skied those contraptions, but I have watched some videos

Here's my take. ATers don't really K+G per se. They walk, run or jog. That still seems awfully uncomfortable for me without being able to flex my forefoot, but they get moving.

They also have a lot of grip, not a lot of camber to flex and are mostly just climbing - so the mechanics are a bit different.

[anrothar]

Cool - thanks for the links.

I have been putting together an AT setup this winter, almost ready to hit the slopes. Maybe something to think about in the future.

Did you find you had to size the boot up for K+G comfort?

How is K+G without a bumper at the front of the ski? Seems like it would feel weird to be able to over rotate.

I went up half a size, to account for foot swelling on multiday tours. Before I cut the forefoot to allow the boots to flex, they were a little weird and uncomfortable to K+G in. I would get foot pain the first few long skis on the season and the motion didn't feel very natural. After cutting that area out, they feel about like a stiff flexing NNNBC boot for K+G, only without the twisting and a lot more stability.

There's been some back and forth over bumper necessity here. I don't find it to reduce K+G control, efficiency or speed over NNNBC on the same ski. I'm still of the opinion that the toe bumpers main purpose in diagonal stride is to keep the tip of the ski in contact with the ground, in the groomed track, so that the ski swinging forward stays in the track. It also helps with herringboning, which I find to be slower off trail with the AT toe piece set up than it is with NNNBC. The toe of my NNNBC boots does not contact the bumper(wrong, see next post) till my forefoot(toes) come up off the ski, at which point my gliding ski has passed my kicking ski and I'm in the process of transferring my weight to it. So, the bumper could not actually provide any increase in grip, even if it were firm enough to overpower the camber of the ski.

Over-rotation would only happen if I were falling or flailing. In a normal K+G context, your legs only swing so far, so the ski can't swing beyond that.

[anrothar]

I was wrong in my previous post, it does make contact with the bumper, lightly, on both my NNNBC and NNN bindings/boots. I stand by my assertion that the gripping ski should be unweighted(not gripping) by the time you lift your toes off the ski and activate the bumper.



explained at 5:25-5:42

[lilcliffy]

Some input to this discussion.

I have some feedback from Rottefella:

Hello Trine,

Thank you for getting back to me.

I have the following bindings:
NNN-BC-Magnum
NNN-BC-Manual
NNN-Touring Auto
I use the NNN-Touring for recreational Classic skiing on a groomed track.

I use both of the NNN-BC bindings on off-track, backcountry Nordic touring skis (i.e. "fjellskis")- hilly/mountainous terrain.

There is a lot of misinformation on the internet regarding ski technology and physics. A common trend is skiers on free-pivot Telemark and AT bindings claiming that a free-pivot binding offers better kick and glide (i.e. diagonal stride) performance than a cross-country binding with a flexor.

My understanding has always been that the flexor adds some resistance to the binding, producing downward force into the kick zone of the ski. I have noticed that I have a less effective kick- and therefore less traction- when I remove the flexor from the NNN binding. Is my understanding correct?

Thank you,

Gareth

Hi Gareth,
Your understanding is correct. When you go downhills, the flexor makes the binding stable and you get better balance. When you walk, it gives you resistance that feels comfortable, and makes it easier to bring the ski forward after the kick.
On our Xcelerator bindings and Performance bindings you can easy adjust your preferred ski sesponse by napping in place softer or harder flexor. Softer for people with low weight and smaller feet, or on wet conditions, hard where there is a lot of double-poling or hard/icy tracks.

Trine

As well as a tech at Aker's Ski in Maine:

The NNN Flexors provide resistance so that your boot isn't free-hinging where it attaches to the binding. So when you stride and lift your heel the flexor provides resistance. For classic a softer flex is used to facilitate an easy fluid stride, for skating a stiffer flex is used so that the ski stays close to or returns to the foot instead of dangling freely. In BC bindings a stiffer flexor is used for bigger heavier skis and/or more aggressive skiing.
Tim

Akers Ski - Customer Service
http://www.akers-ski.com
51 Akers Way
PO Box 293
Andover ME 04216
207-392-4582

[anrothar]

Some input to this discussion.

I have some feedback from Rottefella:

......
Hi Gareth,
Your understanding is correct. When you go downhills, the flexor makes the binding stable and you get better balance. When you walk, it gives you resistance that feels comfortable, and makes it easier to bring the ski forward after the kick.
On our Xcelerator bindings and Performance bindings you can easy adjust your preferred ski sesponse by napping in place softer or harder flexor. Softer for people with low weight and smaller feet, or on wet conditions, hard where there is a lot of double-poling or hard/icy tracks.

Trine

As well as a tech at Aker's Ski in Maine:

The NNN Flexors provide resistance so that your boot isn't free-hinging where it attaches to the binding. So when you stride and lift your heel the flexor provides resistance. For classic a softer flex is used to facilitate an easy fluid stride, for skating a stiffer flex is used so that the ski stays close to or returns to the foot instead of dangling freely. In BC bindings a stiffer flexor is used for bigger heavier skis and/or more aggressive skiing.
Tim

While Trine does start off with "You are correct", he then goes on to describe their function as everything we've already mentioned other than increasing grip. By 'kick' a lot of instructors and xc ski techs are actually referring to the motion of kicking(swinging) forward onto the gliding ski, as Trine describes when he mentions, "(making) it easier to bring the ski forward after the kick".

-There is no physical way for force to be increased on the bumper when you lift the heel on a weighted foot, as long as your toes remain flat on the ski.

-The softer flex of a classic bumper should not be able to overcome the stiffness of the second camber.

-Unless the skier is a trained ballerina, I have a hard time believing that they are weighting the ski while balancing/pivoting on the toe bar, with no other part of the foot contacting the ski. And that's ignoring the fact that by the time you lift your toes off the ski, transitioning onto the toe bar, that foot will be behind you. In order for it to not be behind you, you would have to be 'standing on your toes, but only on one toe, with an unnaturally flexed ankle. Weighting the ski like that will cause the wax or scales to slip.