Raising the Front Binding.

[Svend]

Max:  I can see they need a reference point.  But I also believe that it's hard to do this statically and that on the snow is far superior.


My question is the assumption that the Center of Mass should be over the center of the ski??  I know of binding mounts with the BOF (ball of the foot) over the COR (center of the running surface), but I thought/assumed that you wanted your center of mass somewhere over the front of the ski in order to bend it (more?).


At least in my mind that's a goal, maybe its a goal because my center of mass is well behind too much of the time.

Jim, I used to think that the BOF-CRS mark was the easy way to find balance and the sweet spot on every ski.  But experience with different skis, and different skiers, has shown this is not always the case.  It's just a starting point (and a good one) for experimenting with moving the bindings fore or aft until you feel the most balanced.

Example:  Terryl skis her Progressors 1 cm behind the BOF-CRS mark, but skis her iM78s about 1cm ahead of the mark.  Ramp angle of the bindings is the same for both skis, which rules out that variable.  This makes me think that sidecut geometry has something to do with the differences from one ski to another, and perhaps flex pattern of the ski (ie. relative stiffness of tail vs. shovel).

You've got the Powerail on all your skis....have you tried moving them fore and aft to see if you can feel the difference? I've done it with all my skis, and I can tell immediately that something has changed.  It usually takes me about half a day with the new setting to decide whether the change was good or not, as I like to put the skis through varying scenarios -- steeps, crud, carving, short/long turns, etc. -- to see if it works well in all conditions.

Bottom line:  like forward lean and heel lifts, finding your balance is something individual and unique to each person, but well worth fiddling with to find that elusive sweet spot.  If you happen to be lucky enough to own some skis that already have a big sweet spot built in, well then you've got a much easier job of it.  My Mach 3's and Mythics are like that, but my Progressor 9's.....not so much  . 

Unfortunately, for techno/engineering/math-type guys like us, there is no simple mathematical golden rule of geometry that will be our fix-all for our ski balance woes.  Sometimes we have to live with all these darned intangibles.  Frustrating, ain't it?

Good luck with this. And don't blow a fuse trying to figure it out.   

[jim-ratliff]

Yes I do play with the Power Rail.  I'm currently 8 mm forward on the Progressor's, but at 0 on the Ski Logik's, but we also need to remember that the boot center mounting point isn't the same for all skis. Line some equal length skis from different manufacturers up against the wall sometime and see if the recommended mounting points differ.


My real point was different.  As part of Diana trying to get me out of the back seat, one of the things I began to feel and use as an external feedback was which part of the ski felt like the center of resistance from the snow. I could, at times, feel like it was half way up the front of the ski, she had me trying to see if I could get it even farther forward on the ski. I was surprised I could feel this difference, and was wondering whether this related to JBotti and others comments about "learning how to bend a ski".


Example. if you come to a hockey stop, where is most of the pressure/resistance from the snow. Are you balanced and skidding on the center of the ski, or on the tail of the ski, or can you get pressure forward and skid on the front of the ski. And this also ties in to the NE-PMTS gathering where pressure management by dynamic balance on the ski was being talked about.  [size=78%]Of course, the guys talking about it were racers, so I'm not sure how much it even applies to me.[/size]

[Svend]

Yes I do play with the Power Rail.  I'm currently 8 mm forward on the Progressor's, but at 0 on the Ski Logik's, but we also need to remember that the boot center mounting point isn't the same for all skis. Line some equal length skis from different manufacturers up against the wall sometime and see if the recommended mounting points differ.

Gotcha -- but just to clarify, I wasn't talking about boot center mounting point.  It was ball of foot / center running surface (BOF-CRS) mark that I was referring to.  As for the factory boot center mark, I pretty much totally disregard that (seems a bit meaningless to me).  On a new ski, I start by using the BOF-CRS mark as an initial setting, then go from there if I feel the bindings aren't quite right.  On certain skis, the BOF-CRS mark happens to coincide with the factory boot center mark, which is great (both our Dynastars are like that); but on others it's way off.

[LivingProof]

The below thread from Epic about binding position mounting is a few seasons old, but, just bumped recently. The author of the first post is well known to the Peak Skier Zone community, but, I will not "out" him. Very detailed and interesting (to use a much overdone word).

http://www.epicski.com/t/97891/bof-mounting-point-method-for-the-21st-century

[HighAngles]

If we get in our time machines and go back to the time before manufacturers printed mounting points on their skis (to be aligned with a boot midsole mark), we would find that most skis of that era were very similar in geometry.  Today's more complex geometries utilizing multiple radii sidecuts were unheard of then (and we're not even discussing the advent of rocker/rise into the designs).  Skis mostly differed in flex pattern and most manufacturers spent their time developing solutions for managing torsional rigidity.

With these older designs, CRS (Center of Running Surface) made sense as a mounting point reference and skiers generally had their BoF positioned over the CRS by the shop doing their mount.  By positioning the BoF over the CRS, the skier's CoM and pressure distribution across the ski length worked very well for providing a satisfactory ski experience.  Unfortunately the shops complained that the process was time consuming and error prone and the industry decided to move toward a simpler mounting solution that was less error prone, but also no longer customized per individual.

IMO, the main problem with using a boot midsole mark is that most skiers do not have boots with a tight enough fit where the boot midsole mark actually corresponds to the foot's midsole point.  Since your foot when buckled into a boot moves rearward, almost all skiers are already rear of the midsole just due to their boot fit.  Couple the rearward position of a foot in the boot with the fact that most manufacturers err on the side of a rearward mount point on skis (to cater to recreational intermediates who generally skid their tails rather than carve their skis) and you can see that the problem compounds itself.

I believe that using BoF over CRS still works fairly well for traditional camber standard sidecut skis.

[Svend]

What relevance does CRS have in a ski that is not a symmetrical design? And how does one verify that one location is better than another?

We've been saying all along that this is just a starting point to finding one's own sweet spot.  IMO, it's a better way to start getting dialed in than the boot midsole mark, and as H-A said, seems to work fairly well with traditional cambered skis.  As it happens, it also worked for me with my Progressor 9's, which are dual-radius sidecut.

As for verifying one location as better, that is strictly personal.  Wherever the skier feels the best balance, tips or tails not overly grabby, tails not washing out, shovels not flapping out of control, relatively even pressure fore and aft on the skis when turning....that sort of thing..... is where he or she should end up.  You know it when you find it, but once there may take a few hours or days just to be sure, and further fine tuning may need to happen.

[jim-ratliff]

What relevance does CRS have in a ski that is not a symmetrical design? And how does one verify that one location is better than another?

Video = Truth  ( I received that bit of information recently from an unnamed PMTS instructor )

Video yourself skiing the same slope with a few different mount locations and see if there is a visible difference in your skiing.

[Gary]

IMO wherever you start....with you in your center or neutral stance, the feedback from energy input fore and aft, sensitivity and feedback should feel equal. Being able to manage the skis from tip to tail with the least amount of body movement, using pressure with the least amount of fore/aft movement is the ultimate goal.

I believe this applies to all specific and genearl all purpose skis.

You've must have an awareness of this feedback or feeling. I'd recommend on a nice sunny day, blue run, if you can adjust your binding easily, move back 1cm and forward 1 cm, compare the response and control and see how it impacts sensitivity to tip and tail.

Also, as said earlier, having boots that fit properly, no slop, is a key ingredient to success in this search.

There are so many variables that impact this...for me, throwing all standards out other than a reasonable starting point..it's all about feel and performance.  best, g

[Gary]

Max, while I would agree that video is a great tool to analyse technique, for me and tons I know, it's response a skier gets. How much effort and how skis respond provides the feedback they get on their skis. Maybe not everyone has the desire to be videoed, they watch, they learn or they don't, but they DO know what they are getting out of their skis...what they feel.

When buying new skis or demoing skis, most I know don't get videoed each time they slap new boards on but most riders will be able to identify how that ski performs and the feel they get tip to tail, edge to edge.

I don't profess to be HH or JC but one thing I have learned is that if I know a particular adjustment has impact on how I ski be it my technique, boots, canting, stiffness, mounting position etc etc etc.....If I recognize that impact and the change it can make, I will apply the ones that give me the best performing response....the feedback, the feel.

Moving a bindings mm or a cm fore or aft...most won't need days on end to confirm feedback...it can be recognized almost immediately. For me, in just a few turns the different response is noticeable. Working with a variety of skiers, I've seen this confirmed numerous times.

Feel at least in my humble opinion, IS ultimately what's it's all about.  G

[jbotti]

I skied on Max's Head Rock N Rolls in Montana recently. They were very different than the skis that I was using with similar dimensions. After two runs I said that I didn't like them, that I didn't like the feel of them. I was lucky that I had HH and Max there because both said to me that I was skiing better on them. The next day they shot video of me on the skis and my skiing was actually better on the Rock N Rolls than any of the other skis that I had been using (off piste in crud). I was much more patient on then and I was using the ski properly, allowing it to arc off piste. Seeing it all on video was an eye opener and it does bring home the point that often times feel is quite overrated as a tool.

It is often painful to again realize that perception is rarely reality when it comes to skiing. Anyone who has ever seen themselves on video can attest to this. What we think we are doing or accentuating we may not be doing at all or if so we have only scratched the surface on our range of motion with that movement (when our feel is telling us that we have maxed it out!!).

At least for me sometimes feel does tell the truth. Unfortunately it has only about a 25% hit rate which really is not good enough  for me to make any decisions based on it.

[Svend]

You can compare for days on end. But without video how do you know if one position is better than another? Unfortunately feel has nothing do with it (unless you happen to be at HH's level).

Hmmm....interesting comment.  I agree that video is a great learning tool, and I don't disagree that it won't show up shortcomings in stance, etc..  You are correct that video would be an excellent fine tuning tool for stance and balance.  But I don't think I need video to confirm that my bindings are too far back when the tips of my skis start flapping around at speed and deflecting in crud.  Or video to tell me when they are too far forward and the tails are washing out in short carved turns.  I can see it and feel it. 

And I can feel it when I hit the sweet spot of balance on the ski, whether it's binding position or forward lean in my boots or ramp angle.  It just feels right.  I don't feel like I have to force my body into an unnatural stance to stay centered and balanced.  I don't feel like I have to exert extra pressure on the shovels or tails to get them to exert even pressure on the snow. 

John, I can relate to what you said about the skiing on the Rock-n-Rolls and how you mentioned you were more patient with them.  I experienced exactly the same thing last year skiing at Banff with Gary and Alice.  I had been skiing hard snow all week on my Progressor 9's, which, as you know, are very quick, snappy, agile and lively.  Then after Day 5 I switched to my Mythics, and after only 1 run both G and A commented how much better I was skiing on them.  I certainly didn't feel it, as coming off of 5 days on the P-9's, the Mythics felt ponderous and heavy and sluggish (but appropriately stable for the off-piste crud conditions that day).  But.....the Mythics forced me to be more patient, more measured in my movements, less abrupt and hurried.  This taught me a valuable lesson about how to ski better on my P-9's -- smoother transitions, more fluid edge changes, letting the skis run flat between turns just for a whisker, letting the sidecut carve nice round arcs....you get the picture. 

I still have a blast on my P-9's, but am learning that I actually ski better (most days) on skis that are smoother and more damp, have a rounder and more even sidecut and more even flex pattern.  My Mach 3's are like that, and that is one reason why I like them so much.

Cheers,
Svend

[jim-ratliff]

You can compare for days on end. But without video how do you know if one position is better than another? Unfortunately feel has nothing do with it (unless you happen to be at HH's level).

I think I disagree. I think most of you higher level skiers have a memory of the feel of skies you like, and like High Angles said, he often had a feel for a ski by the time he skates into the liftline.
I understand the mantra of not trusting feelings when learning, because the comfortable feelings are of invalid movements.
Trying different skis is a different ballgame.

[Svend]

Max, if it's fine tuning you're talking about, I'm not sure that you could see in a video the difference of moving the bindings a 1/2 cm forward or back.  Boot forward lean and ramp angle, OTOH, are things that would probably show up in video very nicely, as they have a more pronounced affect on stance.  But small movements in binding position, as they don't affect stance as dramatically, I think you would have to go on feel rather than visuals.

To your earlier question about trying to understand the BOF-CRS equation, here are some tech articles written by Lou Rosenfeld, one of the Boot Guys on Epic.  There are at least three articles on this subject, plus other good stuff on ramp angle, boot fitting, etc.

http://www.lous.ca/tech-articles.html

This one is particularly good: 
http://www.lous.ca/Tech%20Articles/BootSizeandBindingLocation.pdf

Hope you find them informative.

[jim-ratliff]

FWIW, Lou did the study at Snowbird (funded by Nordica?) that was researching the boot mounting position question, and that resulted in the development (and patenting, I think) of the Campbell Balancer.  Peter Keelty has some old articles on his web site written during the process, expressing the amazement at the visible difference observers could see in the skiing of the test subjects.  If I remember correctly, the test subjects were mostly recreational skiers since Nordica was interested in the mass market application to their skis, but I believe they had some higher level skiers in the test as well.  BoF/CRS came from that study as a close approximation of where the Campbell Balancer would place people.

[Gary]

Max, I agree that small adjustments in binding location does not affect stance.... but I think it does affect ones ability to apply forces equally tip to tail. The least amount of force required to get max performance I've found is always the best.

I believe it's not a matter of where that mounting point is, at center, plus or minus, it's THE spot that allows the rider to maximize their input from a stacked stance ( I refer to as my "attack position") with the least amount of body movement and with equal fore/aft pressure.

When I apply the pressure as you described, I feel the pressure move along 1) the inside edge of my downhill ski from the  big toe toward the heel moving along that edge as the turn is being shaped and finished 2) along the uphill ski edge from just behind the pinky toe to heel depending on how much diverging turn shape or speed management I'm looking for 3) under the arches of both feet skiing pow with less pressure of the feet described in 1 and 2, 4) all turns finish on the uphill edge of the uphill ski feeling stacked, centered under the arches and ready to commit to the next turn. At less that's my story....and I'm stickin' with it! 

Regarding mounting locations,....I recommend to friends, consider the factory mount point only as a starting point. For me, historically I tend to always start my testing point at +1cen. Depending on how an individual skis and works the ski tip to tail...find that mounting point sweet spot that makes edge pressure and edge changes the easiest and most productive. AND yes, video would allow you to confirm or adjust any modifications you make. I find it easy  to see if someone is too far back or too forward on their skis...but in truth, it's just a good starting point. For many...it might make a huge difference on whether they're getting the best performance initially out of their skis. 
G