Xplore vs. 3pin+cables

[lowangle al]

I would equate it to trimming a canoe. In an 18 or 20 foot boat moving forward or back by just a few cm has a very noticeable effect on performance.

[GrimSurfer]

Let’s get some objective measurements and see where they take us…

[TheMusher]

Very interesting and informative video, @Tom M Shows a quantifiable difference in the pressure needed to deflect the boot against the flexor.

It would be interesting to repeat the experiment with scales under the front and back of the ski. That would quantify the difference in tip pressure. (You’d likely have to put a 10 lb weight under the centre of the ski to keep the ski from lifting, but that wouldn’t affect the “delta” in values.)

My theory is that the tip pressure change is small. This is based on the difference in what you measured in your experiment (which is significant but still quite small relative to skier weight).

My theory may be proven incorrect. (It is only a theory, after all). Or it may be correct. Either way, a second



experiment could provide some interesting info on tip pressure differences created by the flexor alone.

Thoughts?

The pressure change might be small, but it makes a noticeable difference in your skiing.

Let’s just take things one step at a time…

You can easily find the answer to your question by comparing the flexors in Tom M.'s film to a free pivot with equal heel lift. You''ll quickly realise that the entirety of that pressure is on the tip with a flexor, and none is in a free pivot.

If you want the abstract (you seem to be into that), 11 lbs corresponds to ca. 49 newtons (at 3 inch heel lift per Tom's film) which you will need to counter at the vector of the flexor's force, in other words the tip of the ski.

[GrimSurfer]

Maybe. A direct measurement / comparison would be useful.

More objective data is never a bad thing and @Tom M appears to have the gear (and natural curiosity) to do it.

[TheMusher]

Not really necessary though.

If you attach your boots to the ski+binding with flexor and push it forward, no weight/force whatsoever will be distributed to the tail.

[GrimSurfer]

Not really necessary though.

If you attach your boots to the ski+binding with flexor and push it forward, no weight/force whatsoever will be distributed to the tail.

Yup… not necessarily. But that isn’t the same as “no”.

The delta between the different flexors is 7 lbs. The binding is set on, or very near, the balance point of the ski. Not that it matters that much because the forces (or torque) might be different. How different? I don’t KNOW. I have some thoughts but these don’t matter when the opportunity exists for a direct measurement.

(Direct and repeatable results with objective data are always better than conjecture or theory based on subjective feelings).

If Tom does this and posts his results, there is a logical second experiment (direct measurement) which can be carried out.

[TheMusher]

Because none of the pressure is in the tail, all of the weight/force consequently falls on the tip (to counter the vector of the flexor). The difference is 7 lbs per yourself.

I’m just saying Tom M. already did what your asking, in essence.

[GrimSurfer]

Because none of the pressure is in the tail, all of the weight/force consequently falls on the tip (to counter the vector of the flexor). The difference is 7 lbs per yourself.

I’m just saying Tom M. already did what your asking, in essence.

He didn’t directly measure pressure at the tips. That objective measurement is a single piece of the puzzle. One of two needed to complete the experiment.

[TheMusher]

Why don’t you show us? Bending the flexor using the tail of the ski would be quite the party trick

[GrimSurfer]

I don’t own an Xplore binding.

This isn’t about the tail. It’s about tip pressure. It helps to “scale” the tail in the experiment to keep things level. Plus, it provides additional data at no expense in time. It might come in useful for the second experiment.

I’m asking for that to be measured. Is that so bad? Is the data from this experiment something to be feared?

I don’t know what the resistance is all about (pun intended).