Leash Thong – Dynafit Speed Rad 2012/13 and Sportiva


This post by WildSnow.com blogger  

Oh la la, DPS Wailer 99 Pure with a new set of Speed Radicals and some Sportiva Spitfires. Ski brakes would be blasphemy with this light of a system, so leashes it is. The Speeds come with Dynafit brand leashes, and they’re cable contraptions without any provision for breakaway. More, I couldn’t figure out any elegant way of making a temporary leash anchor on the Spitfires. So here is how it went down.

Completed rig. Only part from the stock Dynafit leash is the clip.

Completed rig. Only part from the stock Dynafit leash is the clip. Nylon cord is used to attach clip to binding, and to attach Maurelli breakaway tab to the Sportiva. Yes Virginia, I drilled a small hole in the Spitfire tongue for the cord (it's knotted behind.) I tried to just use a loop of cord under the Spitfire tongue, but the Sportiva fit and finish is too good, with no clearance for aftermarket stuff.

Maruelli makes these little tabs to break away at the right force to prevent heinous bodily injury.

Maruelli makes these little tabs to break away at the right force (about 40 KG) to prevent heinous bodily injury.

Simple way I rigged the nice Dynafit clips.

Simple way I rigged the nice Dynafit clips.

For the leash fuse, see Maruelli’s website.

The Dynafit leash is called their “Guide Leash” and is available as an accessory. It has the best clips we’ve seen. Just clip off the steel cable — or use as a stock item. Beyond Dynafit, to obtain nicely sized clips you can sometimes find them at the hardware store, or buy a donor set of leashes such as these from 22 Designs. (If you purchase Dynafit Radical Speed, the clips/leashes come with them.)

For a previous ski leash blog posts, check here.

Bonus shot, these we did not burn.

Bonus shot, these we did not burn. Looking good with the minimalist binding, eh?

Weight of Dynafit stock leash, 35 grams. Weight of homebrew system, about 16 grams depending on lengths of cord. Also note that the new Speed Radical has that bit of steel cable as a leash anchor, which adds a bit of weight but does work nicely (can easily be removed).

Comments

41 Responses to “Leash Thong – Dynafit Speed Rad 2012/13 and Sportiva”

  1. Thomas November 26th, 2012 9:43 am

    Hey Lou, my Italian is not so good. Can these tabs be purchased in the US or on a website with english? Long time tele skier that turned to the Dynafit side the last couple years so I gotta use a leash…cause I am still a dirty hippy at heart.

  2. Lou Dawson November 26th, 2012 10:04 am

    True, we should keep all hippies on a leash.

    You’ll have to try and get information from Maurelli’s website, I have not idea who might be retailing in US. Sorry about the lack of info, sometimes I just go for it and blog about a product without the big commercial side figured out…

    By the way, once I have the dynamometer I ordered, I’ll figure out how to make a breakaway leash out of cord. Should be easy.

    Maurelli’s is nice because it absorbs some shock before it breaks.

    Lou

  3. Matt November 26th, 2012 10:36 am

    Lou- I’d be interested in the Maurelli break away tabs. Anything you can ad through your contacts to provide a retail source? How about a piece on the various ways you can configure a leash to beak away? I like the idea of a little force testing as well. Good info for both the AT and Tele folks.

    Thanks for always keeping me up to date on the gear out there. Even though I am a stinky tele hippy…..

  4. Lou Dawson November 26th, 2012 10:42 am

    Well, we have a list of top ski shops. Let’s see if one of them can be the first to carry some Maruelli products.

    As for breakaway force, thinner shoelace cord is a good start for a fuse link. You can test your own but simply rigging up a drop test with a carabiner and a weight. If you know the weight and the distance dropped, it’s not that tough to figure out the force. Hopefully my dynamometer will work and make it easier to test a bunch of stuff.

    Lou

  5. AVIATOR November 26th, 2012 10:51 am

    @thomas

    pretty much everything on maruelli’s site is in english
    including the safe loop
    http://www.n-w-b.com/

    he’s also very good at answering emails, in english too

  6. AVIATOR November 26th, 2012 10:54 am

    his name is maRUelli, not maURelli…

    SO much easier to google with the correct spelling :D

  7. Lou Dawson November 26th, 2012 11:19 am

    Sorry about that, just trying to get revenge on the semi-english emails from him (grin). Actually, I’ll go back and change where necessary. Maruelli has a weakness on the PR and marketing end. A long time ago he should have started work on his branding, with a simple name that works in multiple languages. Oh well, he’s clever with metals, and that counts for much here at WildSnow! ‘best, Lou

  8. Tim November 26th, 2012 11:32 am

    Maruelli link is not exactly wrong, but difficult to navigate. Here’s a more direct link: http://www.maruelli.com/SAFELOOP/MARUELLI%20SAFE-LOOP.htm

  9. Maciej November 26th, 2012 1:24 pm

    Lou,

    I’m pretty sure the Dynafit clips are designed to fail without too much effort, providing the measure of safety you’re looking for. The aluminum bodies on them are really soft and the retention tabs for the clip wires are really small.

    If you bench tested the Dynafit clips and the Maruelli clips, I suspect you’d find they both fail (intentionally) when subjected to about the same amount of force.

  10. Matus November 26th, 2012 3:14 pm

    I suggest trying plastic zip ties. Not elegant but easily replaceable. Easy to figure out the correct size. However, they should be tested in various temperatures.

  11. AVIATOR November 26th, 2012 3:26 pm

    Ive never seen a dynafit leash that seemed designed to fail like the maruelli safe loop.
    quite the contrary.
    too beefy, too heavy…

  12. travis November 26th, 2012 3:55 pm

    Most zip ties have a breaking-strength rating. 90-120lbs are pretty common.

  13. Michael Finger November 26th, 2012 4:18 pm

    R:E zip ties

    They make cold weather zip ties that are rated for 50 or 100 lbs. Regular zip ties get to brittle in the cold.

  14. Lou Dawson November 26th, 2012 4:56 pm

    I’d not advise zip ties, too inconsistent. I’ve even had some that appeared to get brittle with age. Lou

  15. AVIATOR November 26th, 2012 5:08 pm

    I say they would need to be UV resistant AND cold weather resistant AND changed quite often…

  16. Tay November 26th, 2012 5:15 pm

    Lou,
    Congratulations on 500 pages of Wildsnow blogs.

  17. David B November 26th, 2012 6:11 pm

    Nice set up Lou,

    I would be interested in your feedback on the Wailer 99P / Spitfire dynamics.

    While the Pures are light they require a bit of driving to really make them sing. Hopefully there is enough beef in the Spitfire to do that and if so, you are going to have a huge smile on your face.

    I imagine there will be some fast laps happening that day.

  18. Shredgar November 26th, 2012 7:36 pm

    …and the weight of the whole rig is?

  19. Bill November 26th, 2012 8:07 pm

    The key to a zip tie is it needs something to surround it to make sure it is not hitting a sharp edge or bent over a sharp corner.
    It should be in tubing or something similar protecting it.
    If maintained they are about as consistent as anything you can find.
    Extreme cold can make them brittle, but so is most any other plastic.
    I have used them down to about 0 dg F, without an issue. Have some that have been in use for over 4 years.

  20. Lou Dawson November 26th, 2012 8:21 pm

    Shred, you would ask (grin)! Yea shall receive. I will go out to shop and weigh it right now, even though I was enjoying a warm glow and reaching for the computer off switch….

    The DPS Wailer 99 176 cm ski with Dynafit Speed binding and attached leash clip weighs 65.5 ounces, 1856 gr.

    Sick.

  21. Jim November 26th, 2012 10:03 pm

    +1 on zip ties…too inconsistent, unreliable in the field even with plastic sheath around it. Sheath hides defects also. Cord of known test would be better imho.

  22. Stefano November 26th, 2012 11:23 pm

    Thanks Lou for this post (not jet seen)

    I apologize for my spaghetti english and tricky web site where we are working on.

    The Safe Loop was tested for 1 year at low temperature, icing and UV.
    No problems. The gum is similar to the tire ones.

    We just make it stronger for this winter since we seen that 2 are better than 1 only.

    I try to return asap a shop address in the US since shipping from Italy is 10 euros by registered letter (slowly…), 50Euro by currier… so no sense.

    Thanks
    Ciao
    Stefano

  23. Chet Roe November 27th, 2012 8:45 am

    Lou……instead of drilling through the tongue, why not just loop some cord through the ski buckle wire a couple of cm farther up the boot (to the Maruelli thing), yes a little longer contraption, but……..thanks, Chet

  24. Lou Dawson November 27th, 2012 9:05 am

    Chet, mostly because drilling a small hole is much more elegant, at least in my view… more importantly, I’ve never been a fan of anchoring leashes on boot buckles. They are not designed for that, seems like a good way to cause damage or at the least have the leash come off in a fall when you don’t want it to. But anchoring in a hole does make it so you can’t remove the boot part of the leash unless you untie the backing knot or cut the cord. Thus, my solution is probably best for folks who use their leashes quite a bit and don’t mind something more permanent. Lou

  25. Bill November 27th, 2012 11:06 am

    I should have clarified something.
    In a short coupled setup as Lou shows I could not get anything to work and I do not think cable ties would.
    I was only thinking in terms as with a long spring leash.
    The initial forces in a fall are too high and variable.
    I spent two or three years trying to get short coupled leashes to have a
    consitent breaking point, but came to realize you have to get away from
    the initial forces in a fall and have a very compliant system that will minimize the peak forces. I have boxes of shock cords and short spring cords of various kinds
    but could never get anything to pan out with a short coupling. Cable ties are definitely not perfiect. I have been able to get them to work adequetly by taking care of them, always looking for something better.

  26. Lou Dawson November 27th, 2012 11:21 am

    Sort of like holding a climbing leader fall… the rope has to be dynamic and even that doesn’t work so well without a certain amount of cord between belayer and climber. Thus, I’m thinking Maruelli’s little shock absorber break-away unit is even more important than I gave it cred for.

  27. john nobil November 27th, 2012 9:29 pm

    speaking of hippie ski culture :wink:, whatever happened to those rainbow + tiedie colored powdertails? the guru of all things b.c. in these woods claims they used to exist. personally i’d prefer my freshly sharpened skis to release and get away from my personal space just like a resort ski, but still be findable in the fresh & deep. can someone remember whether those colorful tails did the job?

  28. Michael Finger November 28th, 2012 12:50 pm

    Lou,
    RE: dynamometer
    If you have access to some free weights you should be able to test your breaking strength pretty easily and consistently, especially at the low loads your looking for.

    I’ve also ordered some special low temp zip ties, I can send some your way if you want to mess with some.

  29. Lou Dawson November 28th, 2012 1:25 pm

    Michael, I was thinking the same thing. Just rig up a drop weight test with a recorded distance and amount of weight. Not quite the same as a dynamometer but adequate for figuring out breaking strength.

  30. Josh November 28th, 2012 8:50 pm

    Since people are discussing leashes designed to fail at specific loads, does anyone know how much force is generated in say a high-speed fall on hardpack versus, say, an avalanche?

  31. Stefano November 28th, 2012 11:07 pm

    I hope usefull:

    Lou is right to install short latch because:

    1- Long latch (as seen in first era of skiing) will let ski knock your head
    2- The test with dinamometer change lot with cable dimensions (4mm cable is suggested)
    3- 50kg skiers probably use different ski from 140kg one…
    4- The legs of 50kg skiers or 140kg one can support, for sure, different loads before brake (bones or joints).
    5-Standard latch are at 100kg… for us too much.
    6- Dinamic loads are different from static ones…

    For those reason we suggest the use of more than one Safe Loop (for those alreay have a couple, for free, at Ispo 2012) depending on your weight. (1 for kids till 45kg, 2 for 45-65kg, 3 for 65-90kg, more: no sense). Also this comes for light skimo ski.

    The new one is much stronger and comes directly for the right weight.
    The Lou one (that was used as a gift for the Ispo 2012) has a braking load of 10-20kg depending on the cable you use. We use that for light Race ski.

    We are little and now 100% on Bindings and Natural Walking Plates so new generation of Safe Loop has to wait some month.

  32. Mark November 30th, 2012 10:10 am

    Sweet setup with very nice mods on the leashes. I have a hard time believing I’m more of a leashes guy for bc skiing, but its true.

  33. Zack December 3rd, 2012 10:17 pm

    Hey Lou that’s a nice looking setup you got there! I’ve heard some interesting things about where to mount Wailer 99s and I’m curious where you mounted yours. I’m sure you’ll talk about it when you review them but I’ve got a pair waiting to be mounted but I don’t want to drill more holes than I have to and the things I’ve heard have been radically different. I’d really appreciate any input!

  34. Lou Dawson December 4th, 2012 6:19 am

    Zack, I went with boot center mark without forward or backward adjustment. They’ve got some recommendations on their website, don’t they?

  35. Zack December 4th, 2012 9:39 am

    Yeah, on the website they say boot center mark +/- 1 cm. When I went down to Backcountry Essentials here in Bellingham they had an email from DPS saying something about mounting so the heel of the boot was ~84.5cm from the tail on the 192 but when I put my boots on on the ski in this position they looked to me like that would put them quite a ways back on the ski. I’m going back today to look more closely at this email but recommended was looking pretty good to me.

  36. Lou Dawson December 4th, 2012 9:57 am

    Zack, I’ll bet if you go neutral you’ll be fine as you’re mostly on Cascades natural winter snow with those skis, correct?

  37. Zack December 4th, 2012 6:52 pm

    Yeah they’ll definitely be skied in the Cascades the vast majority of the time.

  38. Kim January 16th, 2013 9:20 pm

    Maciej,

    I can confirm that the Dynafit Guide leash does release/fail in a significant fall situation. Just 3 hours ago I wrapped myself around a tree in Niseko, took it across the shins with skis one side and body the other. Failure occurred through the red aluminium bending open and the spring gate shearing out.

    Result, one broken leash, one slightly strained calf muscle. But an awesome day in 55cm of fresh overnight pow.

    I have a photo that I can send to Lou if anyone wants to see the failure.

  39. Daniel February 24th, 2014 1:01 am

    can somebody help me out and show/tell me how exactly to girth hitch the textile loop of the TLT speed leash into the binding toe piece? every attempt I make seems to jam the toe lever (gets caught between plastic and metal)

  40. Greg Louie February 24th, 2014 8:48 am

    @Daniel – I put the cable loop of the Dynafit Guide leash on my boot, usually over the lower buckle strap, then clip it into the wire that comes with the Speed Radical or make a small prusik loop out of accessory cord to girth hitch through the toepiece.

  41. Daniel February 24th, 2014 8:56 am

    Where in the toe piece does your cord go through? Using the large hole in the lever seems to jam the mechanism. Between platik lever and metal part seems prone to breakage…

Got something to say? Please do so.





Anti-Spam Quiz:


If you need an emoticon for a comment just copy/paste off the following list, or use text code you might be familiar with.
:D    :-)    :(    :lol:    :x    :P    :oops:    :cry:    :evil:    :twisted:    :roll:    :wink:    :!:    :?:    :idea:    :arrow:   
  
Due to comment spam we moderate most comments. Please do not submit your comment twice -- it will appear shortly after approval. Comments with one or more links in the text may be held in moderation, for spam prevention. If you'd like to publish a photo in a comment, contact us. Guidelines: Be civil, no personal attacks, avoid vulgarity and profanity.
Welcome to Louis (Lou) Dawson's backcountry skiing information opinion website and e magazine. Lou's passion for the past 45 years has been alpinism, climbing, mountaineering and skiing -- along with all manner of outdoor recreation. He has authored numerous books and articles about backcountry skiing and is well known as the first person to ski down all 54 of Colorado's 14,000-foot peaks, otherwise known as the Fourteeners! Books and free back country news and information here, and tons of Randonnee rando telemark info.

All material on this website online magazine is copyrighted, the name WildSnow is trademarked.. Permission required for reproduction, electronic or otherwise. This includes publication and display on other websites by whatever means. PLEASE SEE OUR COPYRIGHT and TRADEMARK INFORMATION.

Backcountry skiing is a dangerous sport. You may be killed or severely injured if you do any form of ski mountaineering, skimo randonnee and randonnée skiing. The information and news on this website is intended only as general information. While the authors and editors of the information on this website make every effort to present useful information about ski mountaineering, due to human error the information, text and images contained within this website may be inaccurate, false, or out-of-date. By using, reading or viewing the information provided on this website, you agree to absolve the owners of Wild Snow as well as content contributors of any liability for injuries or losses incurred while using such information. Furthermore, you agree to use any of this website's information, maps, photos, or binding mounting instructions or templates at your own risk, and waive Wild Snow its owners and contributors of any liability for use of said items for backcountry skiing or any other use.

Switch To Mobile Version