Binding Ramp Angle

It's funny. I remember seeing various posts about this topic over the last several years and I completely ignored them. I kinda sorta knew what they were talking about but I didn't have any issues with my mounts so I never indulged. Until now. 

I've been running Plum Race bindings (145 and 165) on my skis for several years. Most of you know that my skis have traditionally been on the narrow side so I never thought I needed more beef in my clampers. When I moved to Alaska a couple of seasons ago I decided to indulge in a pair of real powder skis and mount them with something more substantial than a race binding. I chose the DPS Pure 112 Wailer mounted with Dynafit Radical FT. 

The first time out on them I immediately noticed this "ramp angle thingy" and it made me crazy. I felt like I had to permanently bend my knees no matter what I was sking and my quads flamed out fast. What's up with that?? I guess, over the years I've developed my ski technique so that I prefer having the option to stand up straight and pressure the front of my ski with less ankle dorsi flexion and less knee flexion if I desire. Or something like that. The bottom line is that this new higher ramp was/is uncomfortable.

Now, I wasn't really planning on skiing that set up too often as I got it mainly for mechanical assisted skiing. But recently, I added the Dynafit Grand Teton with Dynafit Speed Radical binders and the problem is now in my face more since I ski that set up regularly. And this brings me to this post.

I've combed the internet for various opinions and solutions for the issue and know that B&D Ski Gear has options for me. I guess I'm submitting this post in hopes of hearing from others with more experience than me with this stuff.

I brought out the calipers this morning and took some measurements. These were telling. I measured the heel height from the ski top sheet to center of heel pins and the toe height from top sheet to pin center. Here's what I came up with:

Dynafit Speed Radical - heel: 44mm, toe: 29mm = 15mm ramp delta

Plum Race 165 - heel: 32mm, toe: 29mm = 3mm ramp delta

Dynafit Radical FT - heel: 51mm, toe: 36mm = 15mm ramp delta

I ski these set ups with the same TLT 5 Performance boot so the actual ramp angle differences should be consistent with identical BSL.

So, the question is what to do? Seems like the biggest shim I can get to put under the toe piece is 6.4mm which will still leave me 8mm higher than what I'm used to. I'm pretty sure I'll notice the difference for the better. It's not that I can't ski with the way it is. I just don't like it. I've toyed with just getting used to it but I think I'm better off bringing all my set ups closer together in this regard.

I'm interested to hear from any readers who've dealt with this issue. Please comment. 

Comments

[Pete]

Hi - interesting post, and blog in general.

I've been pondering this problem too. I made the leap to tech bindings from fritschi for touring / general use a few years ago, choosing plum guides and tlt5's. an amazing difference, but I've always felt that, despite reasonably fat skis and 'early rise' I need to be in the backseat in the soft stuff.

I'd been wondering if boot lean was the issue as i felt i couldnt stand up straight, so last year put in the replacement lean adjuster from dynafit for my tlt5's, which made no appreciable difference to a hard week in france. I'd come across a couple of mentions re delta / ramp angle and thought id try a toe-piece shim this year. My solution has been to acquire a plastic chopping board with flat surfaces (9mm was what i found), draw round the toe piece and get the multi-cutter out. Yet to try it (Switzerland in a couple of weeks) but in theory drops a 13mm delta to 4mm. Think ill notice a difference?

Last year I had a shot at a couple of skimo events here in Scotland and this year bought some skinny race skis and shaved 1100g per foot off - what a difference, and surprisingly skiable on the hard stuff / mud / heather we have here! Now wondering whether I should try shims on those skis too. Would be easy to do as put quiver killers in to share the bindings until I can afford some plum race ones (hope drill pattern is the same), but not sure if will disadvantage the up on skinny skis / make them feel stacked and unstable / risk mount failure?

Interested to hear what you did / if it helped.

[Brian]

Hi Pete,

Thanks for reading and for your thoughtful commentary. Sounds like skiing in your neck of the woods is a Western rodeo. Awesome. Powder in Switzerland will be a dream.

I went out with my Manaslus today which have Plum Race 165s on them. I have to consciously be aggressive in my position forward but I can stand up straight, too, when I want to. It allows for some mid run quad relief when necessary. The steeper ramps of the other bindings put me in the aggressive stance but eliminate the break when I need it.

I don't have the complete answer yet but the shims are on their way so I'll be reporting back soon. Sounds like you were able to work something out in your shop that will do the trick. Be sure to drill some holes in that plastic to shave the weight.

And, yes, you need race bindings for your skimo race set up as soon as funds allow. No question.

[Jonathan Shefftz]

I was already into partially zeroing-out the binding delta as an alpine race coach, so once I got into AT, I just kept using all the same materials: LDPE custom shims from sheets bought at SmallParts.com, and screws from various sources, e.g. ski shop spare parts bins, salvaged obsolete bindings, Slidewright.com (has access to the entire SVST catalog), and occasional access to the Salomon accessory catalog and Wintersteiger website.
The one big difference is that the imparted boot delta for AT also depends upon the location of the toe interface and the extent of the sole rocker. So two different boots that feel the same standing indoors might be very different when clicked into the same binding.
Hence the measurements are really for "pin delta" and also aren't comparable to delta measured for non-Tech bindings.
My measurements can be found at the "Author URL" page, in a spreadsheet linked from the fourth paragraph.
The one constant though is that race and "near-race" bindings (e.g., Dynafit Speed SL & ATK/Sportiva RT) have very little heel > toe pin delta, since the heels are so minimalistic.
But add a large lateral release spring and a fore-aft adjustment tracks, and the heel gets jacked up more. Fortunately for the Dynafit IV/Tech/Classic/Speed and Dynafit Speed Radical, you can just add a Dynafit Vertical ST and Dynafit Radical ST toe shim (respectively).
But add even more heel height to accommodate a brake, and now the delta is further increased to the extent that a "pass-through" shim is going to get ridiculously thick. One solution is to use a two-part shim, like those swap plates, but just the toe.

[Tony]

Quick question, what's the story with the major remount forward on the La Sportiva skis?

[Brian]

Tony,

Well, I'm sad to say that I only have a partial review of the remount. I know that's kinda lame. We've had such a slow start to the season up here that my Cho Oyu arrived and needed bindings before I had a chance to finish testing the GTR. They worked great in that summer snow but I was curious about soft snow performance. Sadly, they sit now sans bindings.

On a brighter note, the Cho's are freaking awesome, so far. Need a powder day to know for sure but I'm pretty excited right now by them.

[Andi]

I'm suffering this problem too, ramp delta is annoying ;-). Since you're THE skimo guy, maybe you have Informations on the ATK bindings ramp delta? Im really interested in the Revolutions and SL Evo World Cup... but all I can find is that Dynafits low tech race has ZERO RD.

[Brian]

Hi Andi,

Thanks for reading. Being up in AK now I don't have access to these sorts of bindings anymore to measure them for you, especially the newer two you ask about. However, Jason Borro at Skimo Co (www.skimo.co) has all the lo-down on the latest goodies. Give him a shout and tell him I sent you. He has never steered me wrong and is my go-to guy for all things skimo.

[billski]

I see the last comment was in 2016. It's 7 years later and the problem of binding delta is still only summed up by old blogs and peoples complaints (including my own).

I posed this scenario to Jeff at Skimo recently- Can I screw the Hagan Core 12 EVO toe piece with an ATK AL14 4mm toe spacer to an ATK R16A adjustment plate? He said yes, since the adjustment plate is secured to the ski in a wider bolt pattern, and the toe piece is secured to the adjustment plate with machine screws, it seems completely do-able. Except it isn't. The machine screws that you would need to secure the toe piece (with spacer) to the adjustment plate do not exist. The machine screws that come with the R16A (5.7 x 9.5mm t-20 countersunk screws) are only long enough to secure the toe piece directly to the adjustment plate, and are 100% proprietary to ATK. Presently, they do not make the screws I would need. No one does. Don't bother checking a hardware store either, you'll be wasting your time.

Will there ever be a full featured touring binding that has zero binding delta? I get it- if you have a long foot, you don't have the delta problem. But for all us skiers with short BSL's and heel lifts in our boots, we do, and there is a HUGE vacuum in this market. Make a decent one and I'll be your first customer. You can even have my old bindings.