Sometimes recommended mount positions are wrong

[shasti]

I have a pair of RPCs, Lotus 120s, and Lotus 138s from DPS. All are the 12-13 vintage. All recommended mount points are ~ 12cm back from true center of the ski. I've skied em. These recommended mount points are clearly too far back.

I also own a Rocker 122 from Salomon of the 12-13 vintage (yeah I bought a lot of skis that year). Its recommended mount point is 3 cm back from the true center of the ski. This is clearly too far forward.

Maybe this has been addressed in the 13-14 versions of these skis but if it hasn't, like an environmentally conscious oil company, you're going to want to think it over before you drill.

When I redrill I'm thinking to move the DPS skis 3cm closer to the tip (from "recommended") and the Sally ski 2cm closer to the tail (from "recommended").

[TahoeJ]

Or maybe you don't ski with a centered stance and really like to drive the tips of your skis. Nothing wrong with this, but it doesn't make the recommended line on any given ski "wrong."

[Fritz]

Yeah good idea to get some recommendations before you drill. That's the moral of the post, right?

[kc_7777]

2011 Legend Pros.....rec was at -19cm. On 175s!

I skiied em like that for a day. People were crying they were laughing so hard in the chair line up. They ripped straight lines well....

Ever since then I research, then measure and then email manufacturer.

Ie even 2012-13 187 Hoji rec is back 2cm from where should be (this year Hoji OK).

K

[XXX-er]

I liked the 11-12 wailer 112 best at +5 from their center mark based on back to back testing with a demo binding

I didn't do any testing I just mounted the older lotus 120's at +1 and called it good

[Spats]

I've found that skis usually ride best when mounted between BOF/CRS and 1.5cm behind it. How to measure:
http://www.gnolls.org/756/howto-moun...urface-method/

It's not an iron-clad rule, especially with skis that have long, slow tip or tail rocker, but I always measure it on new skis to see where I come out -- and if the manufacturer's line is way off, it usually produces better results.

Note that DPS recommends "ball of foot at center of sidecut", which gives better results with long, slow rocker skis -- but it's very hard to measure precisely unless the manufacturer marks it for you.
http://www.dpsskis.com/company/faqs/tuning-mounting/

[shasti]

^ This is a cool idea, although rocker makes the concept of "running surface" more blurry than a traditional ski with camber and a turned up tip and tail.

Or maybe you don't ski with a centered stance and really like to drive the tips of your skis. Nothing wrong with this, but it doesn't make the recommended line on any given ski "wrong."

With research, it seems the RPC is better at +1.5cm from where I put it (which is at 13.25 cm behind true center).

Again, maybe the mount points have been changed for the 13-14 versions of the skis I'm talking about. I'm just saying that sometimes the recommended mount positions are wrong.

[swerve]

I wouldn't say the mount point is wrong. Someone skied them and liked them mounted where they are. If you like to drive the tips going behind recommended can be good, if you like a more neutral stance going forward might be better. Figure out what you like. Compare the mount point of a new ski to the skis you already have and adjust the mount accordingly. I wouldn't go too far from the manufacturers recommendation as you could end up mounting off of the reinforced mounting area on the ski.

[shafty85]

This years' L120s recommended mount is 81cm from tail, as opposed to 80cm previously. I mounted mine with inserts at 80cm and 82cm.

^ This is a cool idea, although rocker makes the concept of "running surface" more blurry than a traditional ski with camber and a turned up tip and tail.



With research, it seems the RPC is better at +1.5cm from where I put it (which is at 13.25 cm behind true center).

Again, maybe the mount points have been changed for the 13-14 versions of the skis I'm talking about. I'm just saying that sometimes the recommended mount positions are wrong.

[LC]

Depends totally on how you ski. Recommended lines are mostly just where the R&D guys think works best, but you don't know what style of skiing they had in mind. I always mark true centre and centre of effective edge (midway between the widest points) and reference those against the recommended line and where I've mounted similar skis previously, bearing in mind where the ball of my foot will be relative to those marks.

[garuda]

Your logic is flawed. You are ignoring the entirety of the design work that goes into a particular ski and declaring something is "wrong" based on pulling a tape measure. DPS are back by design. Move the boot center +3 on a 138 and you will be in the wrong spot for the rocker profile as well as the "sidecut." Same is true of the other DPS. Can the mount be moved around? Yes. Most modern skis are forgiving enough to accommodate a range of mounts (and indeed must due to the various sizes of people skiing them).

Yes you should consider the mount point before drilling. More importantly, you should consider the designer's goals for a ski, their design preferences and the recommended mounting point of a ski before buying it. If you don't want to be close to center mounted, don't buy a rocker 122. Buy a Blizzard or another ski with a more racer-oriented mount point.

The OP is probably just to stir the pot, but declaring by blanket statement that the mounting points are all wrong is itself wrong. Peter and Stephan didn't work for the last 8-9 years on the 138 only to find the "wrong" mount point, for example. Good luck!

[glademaster]

It's splitting hairs to a degree, but you are incorrect in saying that recommended mount points are wrong, regardless of the ski in question. The recommended midsole may not be in the ideal spot for you as an individual, but that does not mean it is "wrong." In most cases, a good amount of thought both on and off snow goes into determining that recommendation.

[bendtheski]

If you demo a ski before buying, you can ask the tech to set the bindings on the line, or any other spot you think you'd prefer. Those lines are a recommendation, not an order.

Demo twice, drill once.

[shasti]

I'm aware the manufacturers think about their recommendations. But all of these 4 skis I refer to would ski better if the mount was moved. Towards the tips on the DPS, towards the tails on the Sally. Maybe it's a slight move 1-3cms, but it's still there.

Whether I like to ski centered or on my toes or sitting with my butt on my skis in the backseat, the recommended mount point should still be placed to make the ski most appealing to the widest variety of stances and styles and turn shapes and snow types. It's the mean, average, the position that will help the skier to perform the best. That's what rocker is about and wide skis and tip and tail taper and every other design development we enjoy: making it easier on the skier to ski the best. These mount points don't do that.

[auvgeek]

the recommended mount point should still be placed to make the ski most appealing to the widest variety of stances and styles and turn shapes and snow types.

No, the recommended mount point should be placed to make the ski perform the way the designer's intended. Whether that's to charge or be playful, to ski soft snow or variable snow.

IIRC, I skied the L120 sp at 0 and at +1, and liked it better at 0. And again IIRC, mofro261 skied the L120 sp and preferred it at -1. Kyber.Pass, who reps for DPS, used to prefer the L120 at +3. Different strokes for different folks and all that jazz.

[OldSchool1080s]

I mounted the 192 112rpc Pures dead nuts on the recommended 0 for a 317 bsl and they fucking kill it. Does whatever the hell I tell it to... Yea it's a lot if tip but it also has quite a bit if rocker out front

[shasti]

I understand that everyone has their own perception. I'm trying to figure out where to mount my boards and why so that I can make good calls in the future.

I wonder if most skis perform best (when skied forward) at -5 to -10cm of true center.

If the above assumption is valid, I wonder how much you should vary this and in what way based on rocker/camber profile, sidecut profile, stiffness of ski, type of snow you want the ski to perform in and how much versatility you want in that, type of turn you like and how much versatility you want in that, and just how you ski.

I imagine that chris davenport likes almost all his skis mounted in the same place. I wonder where kye peterson mounts his skis, I bet it's less consistent.

[stuckathuntermtn]

-7cm, or thereabouts is the typical "all mountain" mount. With rocker, especially tail rocker, I don't really know what the rule of thumb becomes. I would imagine with low rocker on the front of the ski and camber to the tail, you just do it like normal, even if the rocker is long.
Park/twin skis used to have a zero at -5 all the time. Some older "traditional" powder skis were about -9cm.
It's been a long time since I've sold skis, so this may all be worthless information.

I put the boot center on the recommended zero on the ski without the binding and than adjust a little so it looks "right". That is, of course, completely relative to the pilot. I'm using the Moment Ruby as my everyday ski, and the zero line looked really forward to me (they have a big twin tail), so I mounted on the -2 line on the sidewall and to me, it looks and feels right, and I think I once measured it at about -7cm from center. (and that damn tail is kinda annoying.

Less and less do any skis have 1 line on them because it really is a thing relative to the skier.

[Spats]

It's also important to note that the ramp and forward lean of your boot/binding combination will affect the proper mounting point. Someone who likes a racing stance with lots of forward lean will probably want to mount a cm or two farther back than someone who likes a more upright stance. Is your COG over the front of the ball of your foot, or the rear? That's 2-3cm right there.

[Ted Striker]

Spats is right.

The line is what the designer(s) came up with based on certain assumptions i.e. BSL, weight/height/leg length, ability, etc., of the typical skier that particular ski is aimed at. If your body/BSL is significantly different, then a different mounting point might work better for you.

That said, the relationship between your tibia and the center of the sidecut shouldn't vary too much. If it does, you need a different length.

[shasti]

Bumping this because I still want to understand. Are there any other threads about this that I'm missing?

[mntlion]

It's also important to note that the ramp and forward lean of your boot/binding combination will affect the proper mounting point. Someone who likes a racing stance with lots of forward lean will probably want to mount a cm or two farther back than someone who likes a more upright stance. Is your COG over the front of the ball of your foot, or the rear? That's 2-3cm right there.

and both of the above ideas (racer and lots of F lean) will usually be someone less likely to be on a jib ski that skis best in a more centered stance.


Also calf size will play into this. If you have chicken legs, you will be more upright then others on the same set up.

also boot size will play into this (and the ramp angle of the bindings) a 260mm boot vs 360mm boot, a 10mm change from toe to heel will make a different angle overall.

ankle range of motion will effect your options too. If you can flex more, you can get away with a further back mounting point, becuase you can flex so far, and get to a larger range of balance on the ski.


I usually go back of center mark, and have a binding, with 10-15mm ramp change, on a 295mm boot, with skinny legs, and large range of motion.


summery: use a demo binding, that has adjustable toe and heel, and play with your center point. Over the years I know I'm usually on, or 1-2cm back of center

[XXX-er]

summery: use a demo binding, that has adjustable toe and heel, and play with your center point. Over the years I know I'm usually on, or 1-2cm back of center

this ^^ is the only way to do back to back testing on the same run/ same day/ same snow conditions so when you ask "where to mount my new cool skis ?" you get some a bunch of guys posting " I mounted at -x/+x cms and its great " but most skis are great now days so how do they really know if one position is > another ... they don't

I ended up with the DPS 112 at +5 which was an eye openner for me, I tried the JJ's at +2 from recommended which was already quite a bit forward so i think I left em @ recommended, due to insert issues I mounted my stokes at -1 which works cuz I mostly turn that ski with the tails and the lotus120 at +1 by reading the internet and hoping for the best

[GoBig1776]

My wife and I sometimes disagree on recommended mount positions.

[XXX-er]

western or english ?