The NNN/BC Truth Thread

[lilcliffy]

This is awesome stuff arothar- thanks for sharing.

I love hearing about the actual context of conditions that people are actually skiing in. Every technology has its pros, its cons, and its best uses.

Your description of the limitations of NNNBC boots and bindings- given the conditions you are skiing in- totally makes sense. And regardless of boot size- I agree there is a limit to the boot power of even burly NNNBC boots. I have no idea what level of torque the binding will handle. Alpina and other manufacturers used to make much more powerful NNNBC boots- don't know why they stopped making them...Lack of sales, or too much power for the binding?

Your observations regarding the reduced torsional strength of the stitched leather/composite boots, as they get larger in size, is very interesting. Haven't thought about this before...If this is true, do you think it would equally apply to other platforms (e.g. leather/composite 3 pin boots)?

Your ability to innovate, and modify equipment is inspiring.

Number of questions (and please excuse me if you already explained this- and I missed it):

1) Why modify AT equipment, rather than using Telemark boots-bindings?

2) I see what you removed from the NNNBC binding...I assume this creates more physical space to clear snow/ice?

3) I also notice that you removed the black flexor when you made the modification to the NNNBC binding...Was this replaced when you mounted the binding on the skis?

[MikeK]

Sorry for the interruption, but I have an on topic, drama-free post.

Hey, whoaa... watch out or you might be voted off this place

[MikeK]

NNNBC boots in her size have much more torsional 'stiffness'(resistance) than they do in larger sizes. I think nordic boot designers haven't figured out that when they increase the length of something, they also need to beef it up to counter the increase in leverage.

This is an interesting observation but I assume the same would hold true for leather 75mm boots as well.

It makes sense that they probably just scale the soles with no other changes, and I'm pretty sure the Vibram soled boots with Norwegian welts do the same, but I'm not sure there is a lot they can do to really increase torsional stiffness, at least without completely redesigning the sole and/or adding in more bending stiffness.

The stiffest NNN-BC boots (Crispi Svartisen) I have now I'd say are right at the limit of what I'd consider acceptable. Torsionally they are stiff as well, but like I say, those two things are interrelated. My other NNN BC boot (Alpina Alaska) is fairly stiff (too stiff for some apparently) in bending, but so far much softer than the Crispi. Torsionally it feels a little softer, but not a lot. K+G with the Alaska feels a lot more adept for a couple reasons, but the sole flex is definitely nicer. Many people here are familiar with that boot so they have a point of reference. Unfortunately I have none with the boots you mention, but I have tried and flexed some lower end NNN BC boots in the store, and even in small sizes they were much, much softer than either of the boots I'm using.

And hey I appreciate your response on the other thread in the reviews, but I didn't want to steer that off into talking about AT boot touring too much. Thanks for bringing this here.

[anrothar]

This is awesome stuff arothar- thanks for sharing.

I love hearing about the actual context of conditions that people are actually skiing in. Every technology has its pros, its cons, and its best uses.

Your description of the limitations of NNNBC boots and bindings- given the conditions you are skiing in- totally makes sense. And regardless of boot size- I agree there is a limit to the boot power of even burly NNNBC boots. I have no idea what level of torque the binding will handle. Alpina and other manufacturers used to make much more powerful NNNBC boots- don't know why they stopped making them...Lack of sales, or too much power for the binding?

Your observations regarding the reduced torsional strength of the stitched leather/composite boots, as they get larger in size, is very interesting. Haven't thought about this before...If this is true, do you think it would equally apply to other platforms (e.g. leather/composite 3 pin boots)?

Your ability to innovate, and modify equipment is inspiring.

Number of questions (and please excuse me if you already explained this- and I missed it):

1) Why modify AT equipment, rather than using Telemark boots-bindings?

2) I see what you removed from the NNNBC binding...I assume this creates more physical space to clear snow/ice?

3) I also notice that you removed the black flexor when you made the modification to the NNNBC binding...Was this replaced when you mounted the binding on the skis?

1) I'm certain a tele setup would offer more downhill control and would probably herringbone a little better, but the lightest plastic boot tele setup is heavier(but less expensive) than an AT toe piece setup and based on reports I've heard, but not personal experience, is less durable. Unless they're on risers, tele bindings drag on occasional set tracks, even user set, and when skating uphill on firm snow or crust. I feel like the free pivot of the AT setup tours more efficiently over long distances as well. Free pivoting tele setups are much heavier, less durable, and less efficient on the flats, since the pivot is further out in front of the foot. Since my focus is more on distance than turns, that made the decision for me. If I was more focused on turns and downhills, or even singletrack, a 75mm setup would almost definitely be simpler and more ideal.

2)The removed material mainly eliminates a pocket on either side of the space behind the metal toebar grabber where packed or slushy snow accumulates and turns into ice. It consequently creates more space for the snow/ice to clear itself. I skied that setup for @4 years and the binding is still perfectly functional.

3)The bumpers were removed to remove the binding from the ski. I definitely skied with the bumpers installed. Occasionally with the white bumpers, but usually with the black ones.

I've never understood why there is only one outsole/midsole combo option for nnnbc. Seems like it would serve the market better to offer at least two different options. One softer flexing, one stiffer flexing.

I have no personal experience with the varying levels of torsional stiffness in 75mm boots, but the concept is the same. If they aren't doing anything to beef up the torsional resistance in the boots, they will get floppier as you go up in size. I notice the floppiness while skiing, especially toward the end of a long day when I get sloppier, but it's at its most pronounced when using nordic ice skates. We've been doing a lot of that up here the past two years with the exceptionally warm(for AK) winters we've had.

[MikeK]

I've never understood why there is only one outsole/midsole combo option for nnnbc. Seems like it would serve the market better to offer at least two different options. One softer flexing, one stiffer flexing.

I don't think this is the case.

Despite the outsole looking the same on all the boots, I believe inner construction and layup is different for all boots. There are definitely some really floppy NNN-BC boots and some really stiff ones.

[anrothar]

This is an interesting observation but I assume the same would hold true for leather 75mm boots as well.

It makes sense that they probably just scale the soles with no other changes, and I'm pretty sure the Vibram soled boots with Norwegian welts do the same, but I'm not sure there is a lot they can do to really increase torsional stiffness, at least without completely redesigning the sole and/or adding in more bending stiffness.

The stiffest NNN-BC boots (Crispi Svartisen) I have now I'd say are right at the limit of what I'd consider acceptable. Torsionally they are stiff as well, but like I say, those two things are interrelated. My other NNN BC boot (Alpina Alaska) is fairly stiff (too stiff for some apparently) in bending, but so far much softer than the Crispi. Torsionally it feels a little softer, but not a lot. K+G with the Alaska feels a lot more adept for a couple reasons, but the sole flex is definitely nicer. Many people here are familiar with that boot so they have a point of reference. Unfortunately I have none with the boots you mention, but I have tried and flexed some lower end NNN BC boots in the store, and even in small sizes they were much, much softer than either of the boots I'm using.

And hey I appreciate your response on the other thread in the reviews, but I didn't want to steer that off into talking about AT boot touring too much. Thanks for bringing this here.

No problem. I'm fully aware that this is a telemark forum, too. Only reason I think it's relevant is that I'm using the AT setup for telemark goals. I'm not using heel pieces, so it's all freeheeling and most of the same techniques apply.

I was very tempted by the Alaska, and disappointed in Alpina USA's reluctance to bring a size 48 to the US market, but the double boot and reliability of the AT toepiece setup in the conditions I like to ski in took my money.

[anrothar]

I don't think this is the case.

Despite the outsole looking the same on all the boots, I believe inner construction and layup is different for all boots. There are definitely some really floppy NNN-BC boots and some really stiff ones.

Interesting. I was referring strictly to the tread and the grey, sometimes black component it's attached to that I assume is the 'midsole'? Maybe that's all just the outsole/tread though.

[MikeK]

It's very relevant actually... better here than in a product review is all I meant.

It's relevance is that you are using as an alternative to NNN-BC, so since you first mentioned it I've been interested to hear your experience.

Carry on... please.

[MikeK]

Interesting. I was referring strictly to the tread and the grey, sometimes black component it's attached to that I assume is the 'midsole'? Maybe that's all just the outsole/tread though.

Yeah, they all look similar, but in articles I've read in UTE I've heard them talk about difference in stiffness and I've definitely skied some cheaper Alpina boots (1550 I think?) that were way floppier than the Alaska. And my Svartisen feels a tad stiffer. Both the soles of the boots I have look identical on the outside. I think it's all internal structure.

[lilcliffy]

My understanding is that the outsole is designed and made by Rottefella to ensure a perfect match to the NNNBC binding.

Everything else is left to the boot manufacturer- including the flex pattern of the midsole. Here is an email response I received from Alpina in Slovenia when I was considering buying a pair of the BC 1600 for my son:

Hello mr. Gareth

Here below are the answers to your questions:

1. The boot is made in Europe. Uppers are made in Romania and assembly in Slovenia.

2. Stiffness of the midsole that determines the sole flex is 35 Shore D. It is softer than the stiffness of the Alaska model.

3. The thickness of the leather is 2,0-2,2 mm. The thickness of Alaska leather is 2,6-2,8 mm.


Alaska model is generally stiffer boot than BC 1600. It is more reinforced and was developed for more demanding skiers. It provides better stability than BC 1600.

If you have additional questions don’t hesitate to ask and we will provide you our answers.

Best regards!

Janez Novak, Product Marketing
Alpina d. o. o.
Strojarska ulica 2, 4226 Žiri
T: +386 4 51 58 315
M: +386 31 364 897
F: +386 4 51 58 376
E: janez.novak@alpina.si
W: http://www.alpina.si