Is NTN's butt too big?

[jasonq]

craig, the couch offer stands winter or summer, and depending on when you come, i might be able to do way better than a couch.

[televisionary]

Have 27 shell TX Pros, waiting on measurement instructions.

[tele.skier]

Ya' know dostie, there are problems with all boot designs and all gear for that matter. Your point as I understand it is that,... since there are 2 distinct sole lengths for the 2 sizes of NTN bindings, the relative position of the bellows to the duckbutt is discontinuous, making for a vastly difference in percieved feel on either side of the boot size where the 2 binding sizes meet.

For me, at size 30.5, the boots and bindings work, but there's no doubt it's a different feel and mechanical design than 75mm bindings with a heel cable connection. Are you saying that the small binding or the smallest sizes of the larger binding are less workable? I kind of see where you are going with this, but since my boot size isn't near the size break, I am not sure if you are saying the small sole boots are too soft,..... or the smaller sized boots with the large sole feel too stiff... ?

If you could give your preference for which feels better, and why the other boot/binding doesn't feel as good, it would clarify the issue and highlight who exactly who has a more poorly engineered mechanical set up as a result of this discontinuous relationship.. Thanks...

[Dostie]

If you could give your preference for which feels better, and why the other boot/binding doesn't feel as good, it would clarify the issue and highlight who exactly who has a more poorly engineered mechanical set up as a result of this discontinuous relationship.. Thanks...

Does this need further elaboration?

If the position of the 2nd heel relative to the bellows affects tele flex, then ... It would progressively hinder a smooth flex the larger the distance was between the bellows and 2nd heel. Specifically, a size 26.5-27 would be the most affected with a large NTN sole, and size 23 would be worse than a 24 with a small NTN sole.

As my graphs above shows...Scarpa consistently exhibits the shortest distance from the bellows to the duckbutt. Crispi and Garmont/Scott are significantly larger and hence, poorer performing except for larger sizes where I think the leverage of a larger foot renders the difference moot. Your experience confirms that.

[Dostie]

As promised/requested...this should help clarify where/how I determined the duckbutt-to-bellows distance for anterior and distal sides of NTN tele boots.







Thanks in advance for your measurements.

[airinwrite]

You've got your label all kinds of screwed up there. It should read medial/inside for the first pic and lateral/outside for the second. Maybe you're trying to describe something else but the labels are confusing and seem to have no relation to the diagrammed pics.

[Dostie]

Aaronisright,

Picky, picky, picky. Do you always have to be right?

Anterior was wrong. Sorry, apparently I was referencing a diagram that was improperly annotated, thus perpetuating the trouble. Distal is outside. Your corrections duly noted, but I'm not going to update the annotation on the photos. Inside and outside should be clear enough.

[Matt J]

Distal is actually further from the trunk on a limb. Proximal is closer to the trunk.

Aaron is correct that the proper anatomical terms would be lateral and medial.

[tele.skier]

If the position of the 2nd heel relative to the bellows affects tele flex, then ... It would progressively hinder a smooth flex the larger the distance was between the bellows and 2nd heel. Specifically, a size 26.5-27 would be the most affected with a large NTN sole, and size 23 would be worse than a 24 with a small NTN sole.

That only states better or worse.... which is relative.

I was more looking for the analysis of :

A) ....the further the duckbutt is back from the bellows pivot point the stiffer the boot flex is... (Which in my opinion would make the boot more powerful because the more it resists flexing the more it generates tip pressure into the ski, but you may also mean that it's hard to flex for smaller skiers)

OR....

B) .... the closer the duckbutt to the bellows pivot point the softer the boot flex is... (to the point of being unable to generate decent tip pressure to the ski or giving it a prefered smoother flex...)

Depending on which scenario you prefer,... a stiff flexing powerful boot, or a easy flexing boot, the corresponding worst and best scenario's reverse..

For example: If you want a stiff boot and you are a size 26, you would chose either the garmont (but I wouldn't) or size up the the crispi 26.5. If you want a softer flex, you chose the scarpa tx pro,.... because as your graph shows the distance (butt to bellows) for 26 scarpa small boot is 37mm, and the distance (butt to bellows) of large crispi boot size 26.5 is nearly 75mm!!! (twice as long)

...so I'm sorry I don't understand which you think is better or worse, but do see how a 26.5 crispi would feel very much different than a 26 scarpa..... yet they are nearly the same size boot.. Hopefully I am clearly stating my question... which scenario is a disadvantage in your mind?

[televisionary]

I was going to mention that medial/lateral nomenclature thing but only when I got you an answer. The answerless people jumped in first, but here are your specs for a TX Pro, shell size 26.5/27.0:
Lateral: 48 mm, medial: 74 mm.

To clear up proximal v. distal, medial v. lateral, and any other anatomical orientation terms that you might wrestle with:

http://www.medterms.com/script/main/art.asp?articlekey=9210

[Dostie]

tele.skier,

The sensation is that all the pressure on my trailing foot is being driven through my toes, not the ball of foot. I'm saying it is because the sole is physically thicker to create the 2nd heel, and thus, it doesn't want to bend behind the bellows as easily as in front. The existing condition with Crispi and Scott NTN boots may be a benefit for bigger guys, but then you have a system that really only works well for size 28 and larger, or size 25.6-26 for small NTN sole sizes. I hope that clarifies it a bit more.

[Dostie]

... here are your specs for a TX Pro, shell size 26.5/27.0:
Lateral: 48 mm, medial: 74 mm.

Hmmmm. Me thinks maybe you took a diagonal measurement 'cuz your numbers are about 10mm larger than expected. I just added a photo that should help to clarify the measurement axis.

Oh, and thanks for the correction on terminology. Relative to torso was unclear, thought terms were relative to the spine or an extension of it.

[televisionary]

Hmmmm. Me thinks maybe you took a diagonal measurement 'cuz your numbers are about 10mm larger than expected. I just added a photo that should help to clarify the measurement axis.

Let me go look again...after dinner.

[tele.skier]

tele.skier,

The sensation is that all the pressure on my trailing foot is being driven through my toes, not the ball of foot. I'm saying it is because the sole is physically thicker to create the 2nd heel, and thus, it doesn't want to bend behind the bellows as easily as in front. The existing condition with Crispi and Scott NTN boots may be a benefit for bigger guys, but then you have a system that really only works well for size 28 and larger, or size 25.6-26 for small NTN sole sizes. I hope that clarifies it a bit more.

Yes, thanks. I understand what you are discribing, and I agree with you. The standardized binding length makes the boot flex progressively stiffer as the boot sizes get smaller. Then once the binding size changes to the small binding, there's a shift back to a softer flex.

When I skied with "lonetelemarker" he had the original crispi orange evos, which were very stiff. He took a hacksaw blade and made 2 light kerfs in the bottom of his boots so they would flex easier. I don't know if those boots held together for him, but you could PM him and find out. I recall that he said that it made the boot flex easier....

IMO dostie, you should be skiing scarpa tx's rather than Tx pro's. The tx's are a softer, more flexible boot. They aren't as powerful on the "down", but they are powerful enough to ski anything I ski in my crispi's (with a little more patience)

I have said this a lot in the past when certain people have questioned the mechanical properties of NTN. NTN is not mechanically the same and an excessively active 75mm binding, in that when you lift your heel on NTN, heel retention due to a cable connection will NOT instantly generates tip pressure to your ski. That's one of the reasons that Hdiddy's coined phrase, "drive the cuff" was an accurate discription of the technique that works best on NTN's mechanical design. For skiers who like very active bindings (the hammerhead on 5 crowd) and don't want to modify their technique, I would always reccomend they stick with a heel cable binding, because the different mechanical properties of NTN usually require some adjustment in a skier's technique....

Do your stiff soled boots feel the same in NTN as they do in TTS?...

[Dostie]

Yes, thanks. I understand what you are discribing, and I agree with you. The standardized binding length makes the boot flex progressively stiffer as the boot sizes get smaller. Then once the binding size changes to the small binding, there's a shift back to a softer flex.

Indeed!

When I skied with "lonetelemarker" he had the original crispi orange evos, which were very stiff. He took a hacksaw blade and made 2 light kerfs in the bottom of his boots so they would flex easier. I don't know if those boots held together for him, but you could PM him and find out. I recall that he said that it made the boot flex easier....

I thought of doing that from the inside on the Crispi Shiver's. There are some ribs of material that I could remove that might help. My concern, as you mention, was that the shell would eventually crack there.

IMO dostie, you should be skiing scarpa tx's rather than Tx pro's. The tx's are a softer, more flexible boot. They aren't as powerful on the "down", but they are powerful enough to ski anything I ski in my crispi's (with a little more patience). Do your stiff soled boots feel the same in NTN as they do in TTS?

I do and they are more than enough boot for anything I'm willing to ski. The bindings do ski a bit different, and opposite of my expectations. IOW - the stiffness of the boot flex is more obvious with TTS, less obvious with the NTN Freedom binding. I did not include the Freeride in the test. It is an irrelevant binding for me since its free-pivot performance is noticeably reduced compared to Freedom, let alone TTS or Switchback or Axl, etcetera.