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The cold world of skimo & alpine climbing

The cold world of skimo & alpine climbing

Tuesday, April 30, 2013

The skinny from the inside..SKI specific.

I have been working on a "ultimate ski quiver" thread for a while now.  Off from the typical topic of pure climbing.  But winter climbing and alpinism incorporates a lot of skiing in my world so I think it is a topic long over do. 

Having worked in ski shop and been certified by everyone making bindings at one time or another to mount skis, the more detail I look at in skis today the more confusing it gets.

What I have learned quite quickly is this: Don't assume any ski manufacturer's info is spot on for mounting points.  Make sure to give your ski shop specifics on what you want done and where you what your bindings mounted.  Bottom line is, the technician is responsible for the mount.  And you need to measure EVERY pair of skis prior to pulling the trigger on the drill. .  

The one of the best ski related web sites is: 

The owner Lou Dawson is a long time climber as well and one of a small group of Colorado climbers first doing hard water ice and mixed there and else where.  What Lou doesn't know someone else generally will.  But even there don't let them put you off any question you might have.

We've done a couple of reviews of the Lo5 and Hi5 La Sportiva skis here @ Cold Thistle.  And I'll be doing  updated reviews on the Lo5, Hi5 again and Hang5 and the GTR soon, among others.

But for those into such things if pays to ask questions.   I wanted to know how weight and mount points were chosen on the Lo5 specifically.  Colin Lantz the director of winter Sports at La Spotiva answered.  The original thread is here:

Author: Colin Lantz
Lou - Pavel - Dane: Just caught up with these posts about weight and mounting location. Regarding the weights, Lou pretty much has it correct. For a new ski model we use the first skiable prototypes (which are also the salesman samples) to get the weight. Typically only one or two sizes is created at this early development stage and so we calculate the remaining sizes using a formula that is more or less 10g for
each 1 cm in length adjusted for different width skis.

When we went to press with our W12/13 dealer workbook the weights were based on these prototype/salesman samples. For the Lo5 this took place in about October of 2011. The POP product stickers that Dane mentions are produced in the early spring to be ready in time for the bulk production of the skis at the factory. In this case, that would have been about April 2012. The bulk production of the skis takes place in May/June. When we receive the skis in our warehouse the first thing we do is QC everything from graphics, to flex, to weights. We spot check 10% of the skis and if everything is in spec then we OK them to be shipped out to dealers. If something is out of spec then we start ratcheting up the spot check percentage and if we keep seeing issues then we check 100% of the production. In the case of the Lo5 we immediately saw that the weights were heavier than the protos and we duly changed the weights of the web site to what we found in the actual production and of course put the updated  weight specs in the next (W13/14) dealer workbook.  This was the first year we put the POP stickers on the skis. In hindsight, it probably would be safer to not print the weights on these.

The product development cycle I’ve described above is pretty standard in the industry and is surely the cause of many weight inaccuracies published by ski manufacturers. It is what it is and we do our best to be accurate and transparent when it comes to technical specs on any piece of gear we put our name on. We understand that our customers are very technical and we feel that they deserve and require accurate product specs. It is not our intention to “trick” anyone.

As for why the Lo5 came out heavier than the original protos, we are still investigating and trying to understand what happened. Weight variations of plus or minus 30 to 50 grams is not out of the ordinary for ski production. For typical traditional wet layup ski productions it is just impossible to 100% control the weight of the ski down to the gram. Wood is a natural material and it is practically impossible to verify that every ski core is exactly the same weight. The other big factor in weight variations is the amount of glue/resin applied and the amount that is squeezed out of the mold when it goes into the hydraulic press. It’s like building hundreds of paninis (Italian sandwiches) and expecting everyone to weigh exactly the same. Like I stated above +/- 30 or even +/-50 grams is OK, but in the case of the Lo5 we were seeing weights heavier by 180-200 grams. It’s not the weight we targeted for the ski but after getting tester and customer feedback we were very pleased with the performance of the ski at the production weight.

Regarding the mounting location – here’s the how our process works to set the boot center. When we produce the protos/samples we set the boot center with the technical assistance of Mr. Tua. We then ski and  check these “theoretical” boot centers using a set of the prototypes with a rental binding that allows you to move both the toe piece and the heel piece for and aft. Our test team does this here in Colorado and we duplicate the process with a test team in Italy at La Sportiva HQ in Ziano. Each test team is typically 3-4 people and we try to test in different conditions to make sure we are not soft snow or hard snow biased in the boot center location preference. Typically the theoretical bc is pretty damn close, e.g., the LO5 188 proto/sample was marked at 78cm from the tail and after  checking/testing with the above method we moved it forward 1.5cm to 79.5cm. The boot center indicator on our skis is an arrow and this is stamped on the ski along with the serial number. Each ski is measured and the bc mark stamped according to our spec. For the Lo5 (measuring from the tail) the bc marks should be @70cm for the 168, @74.5cm for the 178, and @79.5 for the 188. So, that’s the skinny on how we set boot center. In the end this is a very personal preference as many experienced know and understand. Boot center should always be looked upon as a recommendation by the manufacturer and one that is chosen to best serve the largest part of the customer base.

Hope that helps. My apologies for the weight discrepancies. We’ll try and control this on next years production and get the weight back in the target window originally spec’d in the Lo5 product brief. Based on the feedback we’ve been getting in other venues we’re pretty pleased with the way the Lo5 turned out.  It seems to have hit a good balance between weight, surface area, and performance, with the latter being particularly praised. Peace out. -- Colin


Ian said...

I bought the Lo5 because LS said they were 1400 grams. I understand +/-50 grams but 250 grams is BS. LS knew the weights were wrong as soon as the pre-production models hit the docks but they still went to press with the old weight. I probably wouldn't have bought them if LS had labeled them correctly.
I think the boot center marking is over stated. I just wanted to know if I had my bindings laid out correctly.

Dane said...

Colin @ La Sportiva is standup guy imo. It is tough to catch all the details in a new product. He's been up front with what happened and why. Good enough for me. I wasn't happy about the difference in weight either (and I buy my own skis they aren't given to me) The skis weight came in (out of 4 pair weighted) higher than what Wildsnow came up with as well.

For a few of us it made the difference between a ski we would use and one we wouldn't. There were better options no matter how well the ski performed on snow.

Boot center marks? That one is a totally different story. I'll have more details on that issue in a final follow up review from 4 of us using the Lo5 skis this season.

My take on that one is..."it is a very BIG issue" when the ski gets mounted 1.5 or 2cm off center. Another point that would keep me off the ski (any ski) if mounted that far off center and incorrectly for the particular ski design. Think not? Move your bindings 2cm back on your 178s and get back to me on their performance. There was a reason W-Snow moved their pair of 188s 1cm forward. And it is not enough IMO. As it turns out, that is not enough in La Sportiva's opinion either.

I think the Lo5 is one of the better 100mm under foot skis around for my own use. But not if it is mounted incorrectly.

Ian said...

Lou said they moved the bindings forward to see if the chatter the tester was getting would change. He stated that he didn't think the ski performed any different but he used the ski after remounting the bindings and not the reviewer. The ski in the review was a pre-production demo and LS moved the boot center mark forward so the ski you and I have already have mounting locations forward of what is shown at Wildsnow. Lou also switched bindings in the process as well; there are two different hole patterns on the test skis.

I'm going to ski them, if they suck worse that I suck then I'll consider moving the bindings. I plan on using these skis for touring and transportation so the weight is a bigger issue to me than the boot center location. I mounted the bindings .5cm forward of the mark to accommodate a longer boot so I'm reluctant to really worry. I'm going to ski them Friday so we'll see.

Dane said...

Ian, the one thing I have learned/relearned again this season is never, ever trust what the ski is marked. Your ski might well be perfect. I wouldn't make any assumptions about my 188s.

I had the same issue with a pair of DPS skis this winter as well. It isn't simply a La Sportiva issue. But a industry wide issue that pays to keep track of on your own gear.

Colin mentioned in his comments above, "For the Lo5 (measuring from the tail not the skin cut) the bc marks should be @70cm for the 168, @74.5cm for the 178, and @79.5 for the 188."

My suggestion? You might want to take a moment and actually measure your pair. Between the guys I work with and myself we had one pair of 167s, 3 pair of 178s and one pair of 188s. Plus a few more 188s Colin measured in house at La Sportiva for me. I'll get into the details shortly in the Lo5 review where all are involved.

It might not make any difference to you or your skiing. It does make a difference to me.

Ian said...

The boot center mark on my ski about 1cm short (to the rear) of Colin's measurement. I had already measured the ski. I understand what you're saying and if my bindings were mounted 2cm-4cm back I would probably feel different. We'll see.