Is there a point of diminishing returns on ski length? I'm mostly gearing this towards race skis, mainly recreational race skis.
(Yes part of this questions is because I'm in the market for skis and I have a couple of months to obsess about it. Trying to be honest)
I know old school was, go long and with today's skis you can get the same surface area on the base with a much shorter ski. Without a doubt today's technology can make a short ski as stable and smooth as long skis of the past.
What I'm trying to figure out is; what is the most efficient ski length for a particular person? There are a thousand threads here that tell us that this ski should be head height for that style and ability and this type of ski should be chin height; yadda, yadda, yadda.
A short all mountain carver turns wicked easy. An FIS GS ski will turn at speed. I see racers all the time, smaller than me, carve skis that are the same size for the racers over 6 inches taller and 40 pounds heavier. Outside of bragging rights, why?
I know some of this depends on ski construction and turn radius, but just because you can carve a 180cm ski, is that the right length you should be on? If you are on the exact same ski in a 170cm or 190cm, what would you gain or loose?
From skiing on my Elan SLX race stock skis in 155cm, I know that if I use them on a NASTAR race course, I'm slower than if I'm on my Elan GSX race stock in 176cm (they just so happen to be the same year and set up fairly identical so I think this is a good comparison). This I believe is attributed to the same force being applied to a surface of the ski's edge and since one is longer than the other, one digs in more and one rides the surface more. Just like comparing a long ship and a short boat in choppy waters.
When I ski the 155cm I wish it was a little longer and sometimes I wish the 176cm was a little shorter. Both are fun and I enjoy skiing them, but the 176 with a 21.2M TR makes me work harder (I'm 5'7" or 170cm and about 170#). The SLX is 11.2M TR This makes me wonder if there is a point where by adding length, all I gain is extra effort and no additional glide. Probably no additional speed either.
So lets pretend that a person skis well enough to be on the PSIA Development Team (this is so you know we aren't talking about me anymore and there isn't an ability issue). Is 5'7" and 170 lbs or 170cm and 77kg. They are looking for a non FIS race ski for tooling around the mountain in. Doing carving demos and maybe playing in the gates here and there. Always on piste and groomers. No crazy Super G speeds. This isn't for any racing that requires a race suit or that has any gear regulations.
At what length would this person stop getting a benefit that isn't worth the effort being put in? What would the most efficient length be? At some point, the extra glide or float while on edge, just isn't worth it.