Nordic Ski Bindings 101

Cross country ski bindings can be a confusing topic to sort out. It has caused many frustrations for both new and experienced skiers alike, when one realizes that their new system may not work with their older gear, or worse yet, they bought the wrong boot for their binding system. Let’s get it straightened out here to help minimize any confusion and future problems.


  1. Boots & Bindings MUST be compatible. Unfortunately, cross country ski bindings are not standardized. Boots and bindings from different systems will not work together. If you are upgrading gear, or purchasing used or new, it is critical that you purchase gear within the same system to assure compatibility and to avoid disappointment.
  2. Which binding system do you have? There are two systems of bindings; SNS and NNN. They are not compatible with each other. Most newer boots and bindings will be labeled. If you can’t tell, measure across the boot bar or the binding attachment to determine your system. XC Binding Measurement System

1 1/8 inch or 27mm  SNS

1 1/4 inch or 30mm  NNN

1 5/8 inches or 40mm  NNN BC


70mm* Three Pin or Telemark

  1. Differences between Skate, Classic and BC Bindings. Within each system (NNN & SNS) are 3 binding types that are designed for a specific skiing purpose: skate, classic and backcountry (or BC) bindings. Classic bindings are designed to balance torsional control at the toe, with sufficient heel lift to aid in hill climbing and diagonal stride. The amount of lift or flex in a binding is controlled either with a toe bumper or a 2nd axes connection in Pilot bindings (discussed under SNS). In some cases flex is measured with a flex number. The softer the flex (more lift), the smaller the flex number. Classic bindings allow for more heel lift than skate bindings, and they therefore have smaller flex numbers than skate bindings. Skate bindings are designed to maintain a powerful push through the entire skate motion, so torsional control and boot/ski positioning and angles are the priorities. As mentioned, skate bindings are stiffer with higher flex numbers than classic bindings.
  1. NNN Bindings – What you should know? Most NNN bindings are manufactured by Rottefella and are licensed to ski manufacturers. Currently, Rossignol, Alpina, Madshus, and Fischer are using the NNN system. Of note: Fischer switched from SNS to NNN a few years back, so if you have some old Fischer boots use the measuring system above to determine which binding system you will need.
  2. What is the difference between NNN and NIS? NNN Bindings include both traditional mount bindings (screw-in) and NIS bindings. This is important to note so you know that NNN boots are compatible with both types of bindings. NIS bindings refer to bindings which slip onto NIS (plastic) plates which are welded to certain skate, classic and touring skis. NIS integrated bindings offer better edge control, binding position adjustability and weight savings. Most midrange and high-end NNN skis are using NIS Plates.
  3. SNS Bindings – What you should know? The companies using the SNS system are Salomon, Atomic and One Way. The SNS system has two types of bindings; single axis (Profil and Propulse), and double axis (Pilot). Pilot bindings have two connection points between the boot and binding, and Profil/Propulse have one.
  4. What are the differences between these models? Pilot (2 axes) bindings are bumperless (no wearing out) skate and classic bindings. They offer more torsional, and tip and tail control, which can be helpful for skating as well as for new skiers learning any technique. Propulse is a new single-axis, classic binding with a bumper, released in 2010, that offers efficient kick, and more heel lift for hill climbing in an ultra lightweight package. Profil, pronounced Pro Feel, is the original Salomon binding (bumper) and it can used for both skating and classic, and either Pilot or Profil boots.
  5. The Backcountry Binding Story. BC, or backcountry bindings, are used on touring and light touring skis. BC bindings are heavier than NNN and SNS Bindings, and the width of the boot/ski connection is wider, providing greater torsional control over a heavier ski. The wider binding can provide greater support in unbroken or ungroomed snow. BC boots are not compatible with any type of NNN or SNS Binding, and vice versa. Also, NNN BC and SNS XAdv BC boots and bindings are not compatible – they must match their system counterpart. They are used for ski touring in deeper, untracked snow in rolling to flat terrain. They are not designed for ascending and descending steep terrain.
  6. 3 Pin and 70mm Bindings. 70mm Bindings and boots are measured across the front of the contact area of the binding or across the front of the boot. Rather than use an axel and clamp design like the others, 70mm bindings use either a matching three pin/hole design on the binding and boot with a clamp on an extended soul in front of the toe, or a toe retainer bar with a spring-loaded cable and heelbinding. These bindings are used for rugged touring, steeper terrain, and heavier skis, or for skiers who prefer a 3 Pin boot. The 70mm width of these bindings rub badly on 65mm groomed tracks/rails and even in skied-in tracks (not recommended), slowing the ski and the skier’s progress dramatically.

Sizing or Fitting Cross Country Skis

Sizing cross country skis is a bit of a misnomer. Different types of cross country skis are fitted/sized differently. Single camber skis such as Metal Edged Touring Skis are sized by length. Double camber skis, which include all adult skis are flexed by skier weight. Here is a simple breakdown of how different types of skis are sized or fitted.


Sized by Length:

Metal Edged Touring Skis, and all single camber skis, are sized by length. The skier will always be gliding on the grip zone/pattern with these type of skis. See each particular ski model for sizing parameters.

Kids Skis for ages in the 5 to 7 year old range are also sized by length and skier height because the skier’s motor skills have not developed enough to maneuver longer skis.


Fitted by Flex:

Junior Skis (approx. 8 to 12 years old) should be flexed and fitted by the skier’s body weight. Generally, other factors such as height and skier ability will play larger roles with this fitting because of potential skier growth, and because many skier’s weight/height profiles vary widely.
Adult Skate Skis are fitted using compression tests for overall flex, and tip and tail flex to determine optimal skier weights and snow types that will be best for the ski.
Adult Classic and Touring Skis are fitted using half-weight and full-weight compression tests to determine climbing/glide ability, grip zones for hard wax and klister, and glide zones for maximum glide.

Ski Selection & Trail Type

What type of ski (and ski width) is best for the type of skiing you enjoy most?

There are two important questions that need consideration before selecting a ski. The first is “What type of trails do I have access to, or enjoy skiing the most? And the second question is What kind of skiing, or level of exertion, do I prefer when skiing?

Trail type and available trail grooming will dictate the type of ski techniques that can be used, which effects the ski type and ski width. Evaluate and determine the kinds of trails and terrain you will ski. The following is a quick visual reference to help.

Groomed Terrain 

This is a groomed trail with flat “corduroy” on the left and groomed tracks, or rails, on the right. Skate skiers ski on the corduroy, while classic and touring skiers generally ski in the rails. If the majority of your skiing is done on groomed trails, then you can choose between the three ski types (Light touring, Skating,Classical) to match your skiing expectations.

For groomed terrain only, a ski width between 43mm and 50mm is optimum. The narrower skis are race and performance skis, and the wider skis are light touring widths.

For both a fitness and a touring orientation, a ski width from 50mm to 55mm works well. The narrower widths are faster and more appropriate for fitness. Wider widths are nice for recreational workouts and for skiers seeking more stability.

We do not recommend a touring ski wider than 60mm, or a metal edged touring ski for these types of trails. The skis will rub (or not fit) against the rails slowing the ski substantially.

Skied-in Tracks

This is a skied-in track. These tracks are made by skiers following the same tracks. They are not groomed, which makes them less stable and consistent than groomed tracks. Skied-in tracks are very common in both suburban and backcountry venues.

Light Touring Skis are the best choice for skied-in tracks.  Skis 50mm and wider will work, however skis 53mm to 60mm have the best balance between stability and efficiency, or speed. Narrower skis are good choices for shallower snow depths (4 to 6 inches), and unmaintained parks or golf courses. Wider skis work well for new skiers, and those skiing in deeper snow and backcountry environments.

Untracked Terrain

Snow depth and steepness of terrain are important considerations.

Light Touring Skis with 59mm-60mm widths work well for flat and rolling terrain in  snow up to 8-10inches – not deeper than mid-calf.

For flat and rolling terrain in snow deeper than 10 inches or mid-calf, a touring ski with a width of 60mm or wider will provide the float necessary for deeper snow. BC or 3-pin bindings will be needed for skis wider than 60mm.

For steep ascents and descents in deep, untracked snow, a Telemark or Randonee set-up is your best choice.

** Note: Backcountry skiing is the term generally used to include both Telemark and Randonee skiing. This is not to be confused with BC boots and bindings, which are designed for cross country ski touring and not for steep descents.


Exertion Levels and Skier Expectations

There are a variety of different expectations when it comes to cross country skiing. Knowing what your expectations are will allow you to match the appropriate gear with your skiing style.

In terms of intensity and exertion, skate skiing and classical technique can ramp up to an intensity level as high as you want to take it. These skis are narrow and fast for packed, groomed terrain.

Ski touring can take place on both groomed and ungroomed terrain. The exertion and pace can range from a leisurely walk to an aggressive stride. Wider skis will most likely suit the leisurely skier, where narrower skis will be preferred by fitness skiers. The mid-range widths of 53-54mm are the most versatile for a variety of conditions and intensities. Blending the trail type and snow depth with the skier expectation is the best plan when considering light touring skis.

Deep, untracked snow has a similar intensity level to snowshoeing. Experienced skiers may choose to go with wider light touring gear (60mm max) for the lighter weight and faster potential pace, while new, or less aggressive skiers may choose a wider, more stable BC set-up.

Tips for Ski Selection:
» New Skiers looking for more stability should select skis on the wider end of the ski range for each terrain type. New Skiers should also search for groomed trails and skied-in tracks for more stable ski surfaces to start.

» Pick a ski for the type of skiing you do most often, not the most extreme condition you might face.

» Think about your lifestyle, and the time available for skiing when selecting a ski.  Is skiing after work on skied-in tracks more important than skiing on groomed trails on the weekend, or vice versa?

What Kind of Skier are You?

Defining the type of skier you are is critical to selecting a ski and boot that will meet your expectations, particularly over the long haul.

Adventure/Backcountry Touring: Adventure skiers seek the untraveled experiences involving hiking on skis usually done in deep, untracked snow in flat or rolling terrain. Some skiers use this gear (BC) for maximum stability, however these skis are not designed for efficient kick and glide, and they will not fit in groomed rails. Gear used: Backcountry (BC).

Touring: Ski touring on groomed or untracked trails with snow depths up to mid-calf. Ski touring encompass everything from a leisurely walk on skis, to exploratory tours in pristine natural areas, to a heart-pounding ski tours for fitness. Gear used: Light Touring.

Sport/Fitness: This category of skier skis for fitness or recreation and is usually skiing on groomed trails using a specific technique such as skating or classical. Gear used: skate, classic and narrower light touring.

Racer/High Performance: This type of skier is looking for ultimate speed and performance in skate or classic gear for groomed trail skiing. Gear used: High-end skate and classic

Backcountry Skiing: Skiers traveling in deep untracked snow seeking steep ascents and descents, and/or multi-day excursions. Gear used: Telemark & Randone

If you don’t know yet what kind of skier you are, here are a few options to consider. Think about renting skis and taking some lessons to give you a better idea of the types of cross country skiing. If you can’t decide between categories, waxless touring skis can be the most versatile from a trail type and exertion level standpoint.

Ski Flex: Why Is It Important?

Ski flex is the foundation upon which all other factors, such as ski length, skiing experience, body type, and firmness of snow, help guide our ski selection.

For skating, a ski that is too soft will bottom-out creating a pressure zone under foot that makes the ski feel sluggish, slow, and “squirrelly” where the tip and tail pivots around the mid-section. Pick a ski that is too stiff, and you’ve got a ski riding on two pressure zones that again slows you down, and creates an unstable, poor handling ski.

For classic skiing a poorly fitted ski will ride on the kick zone if too soft, or have difficult-to-impossible grip if too stiff. The handling characteristics mentioned above are important here as well.

A well-fitted ski is important for all skiers, not just racers. Ski racers have long known the importance of flex and its relationship with body type and snow surface conditions. But many recreational and performance skiers should recognize its importance as well. Top-of-the-line skis come from the factory with half-weight and mid-flex numbers that give us a good starting point for ski selection. Most ski models, however, do not give us that information which means a reliance on the weight charts (which can range up to 30 pounds per length of ski), if you do not have a flex-tested ski.

At Nordic Ski Source, we digitally flex test every ski, so we can make an accurate ski flex recommendation to all skiers whether they have racing ambitions or not. This recommendation will become the foundation of the ski selection process. We then introduce the other ski selection factors to help fine-tune the actual ski selection decision.


How to Buy Classical Skis

Classical skis differ from touring skis in width and speed. They are designed for groomed trails, and used for fitness, training and racing. They come in both wax-able and wax-less models. The long-term enjoyment of your classic skis is dependent upon having a ski that flexes properly for both grip and glide.


Classical Skis

Ski Width Determines Stability/Speed

Race skis are generally in the 44mm to 45mm range in width. Efficient fitness-oriented classical skis are in the 46mm to 51mm range. In widths that overlap in both classic and light touring skis, classic skis will have longer lengths allowing them to track better, as well as offer more speed. Light touring skis are shorter, more maneuverable, and many times have more sidecut. Both are excellent choices and it may come down to what you are used to, and your expectations. Usually, a beginning skier will choose the more maneuverable light touring version.


Ski Flex Testing Determines Grip and Glide

Next, for both wax-able and wax-less skis we flex test at the skier’s half weight to determine the grip zone on a wax-able ski, and the glide on a wax-less ski.

Wax-less ski flex testing: A digital flex-tester is used to determine the characteristics of a wax-less ski. We flex classical race skis for both hard wax and klister conditions. Hard wax skis have longer and lower bridges than klister skis. Sometimes these correspond to “Cold” vs. “Warm” skis, but that is not always the case. For a universal ski that can be used for both hard wax and klister conditions, we will use a stiffer flexed hard wax ski.

Wax-able touring ski flex: For all wax-able skis we use the skier’s half-weight to map out a grip zone which helps us determine if the ski is too stiff or soft. We mark the bridge (gap) at .1mm, .2mm and .3mm (if necessary) to determine how many layers of hard wax are needed on certain portions of the ski. We also mark the .4mm bridge for the klister zone if the ski has a high enough bridge.

The red lines are meant to represent the layers of wax needed on certain portions of the grip zone. The blue line is a gap between the bottom of the ski and the testing surface at the skier’s full weight. This area is called residual camber, and it needs to marked and addressed with additional wax for effective kick.


Wax-less Touring Ski Flex Testing

With wax-less skis, we look at the bridge at half-weight to see how much of the pattern is off the surface for effective glide. We have found that the most important characteristic for most skiers is to have the ski compress fully at the skier’s full weight. This characteristic allows for effective grip on uphills and a more relaxed kick in variable terrain. At full weight if there is residual camber on a wax-less ski, the grip/kick will be difficult on uphills and we will look for a softer ski.

How to Buy Touring Skis

The long-term enjoyment of your touring skis is dependent upon having a ski that flexes properly for both grip and glide. We combine the proper flex with a ski width to match the terrain and your skiing expectations.


Ski Width Determines Stability/Speed and Suitable Terrain

First, we will select a ski width that best accommodates the skier’s ability level and the trails and terrain they expect to ski. Beginning skiers who have no previous experience and are not yet comfortable on skis may want to adjust to a slightly wider ski.


Light Touring vs. Touring vs. Backcountry Skis

To keep it simple we call skis that can be effectively skied with NNN or SNS bindings and boots, light touring skis.These skis lack metal edges and are 60mm or narrower in width. BC (backcountry) skis, with or without metal edges, are too heavy for light touring gear. They need BC boots and bindings for torsional control over the heavier ski. Backcountry gear is used for deep snow and rough frozen terrain..


Ski Flex Testing Determines Grip and Glide

Next, for both wax-able and wax-less skis we flex test at the skier’s half weight to determine the grip zone on a wax-able ski, and the glide on a wax-less ski.

Wax-less ski flex testing: Use a digital flex-tester to determine the characteristics of a wax-less ski.

Wax-able touring ski flex: For wax-able skis we will use the skier’s half-weight to map out a grip zone which helps us determine if the ski is too stiff or soft. We also will mark the bridge (gap) with different feeler gauges to determine how many layers of wax need to used on certain portions of the ski.

The red lines are meant to represent the layers of wax needed on certain portions of the grip zone. The blue line is a gap between the bottom of the ski and the testing surface at the skier’s full weight. This area is called residual camber, and it needs to marked and addressed with additional wax for effective kick.


Wax-less Touring Ski Flex Testing

With wax-less skis, we look at the bridge at half-weight to see how much of the pattern is off the surface for effective glide. We have found that the most important characteristic for most skiers is to have the ski compress fully at the skier’s full weight. This characteristic allows for effective grip on uphills and a more relaxed kick in variable terrain. At full weight if there is residual camber on a wax-less ski, the grip/kick will be difficult on uphills and we will look for a softer ski. Different ski models have various designs and/or wax-less patterns.

4 Critical Steps for Choosing Cross Country Skis

Your best ski choice is ski that fits, and one that is designed for your skiing style and purpose.

#1: First, select the appropriate type of cross country ski. Ski type is chosen based on the type of skier you are and the terrain you plan to ski and the technique you plan to use

#2: Select the ski model(s) that are designed for your expectations, and fit within your budget.

#3: Work on ski fit. THE most important factor in your long-term enjoyment of your skis is PROPER SKI FLEX and matching the appropriate flex to the skier’s weight along with a number of other factors. Weight range charts are only a starting point particularly for mid level skis. To ensure an accurate fit, all adult (double camber) skis should be individually flex tested using a flex tester (pictured below). Without this critical information, the purchasing process will be relegated to guesswork.

#4: If you have boots that you would like to use with the skis, keep your boot-binding system in mind while looking at skis. Click here for a complete explanation of NNN and SNS binding systems and compatibility.

Ski brands offer differing ski lengths and design strategies. With our expertise, we can analyze all of the various ski options to pick the flex and length of the ski brand that fits you best. Other factors to consider are listed with each specific ski type.


End of Season Ski & Boot Care

Once the last of the season’s snow melts it is time to think about putting your ski equipment away for the summer and making sure it stays in a good enough condition that you can hop straight back on to it next year.

The easiest thing to do would be to take your skis to the nearest ski shop and ask for them to be professionally tuned to get rid of any damaged areas, and then waxed ready for early season conditions. However, to save those all important pennies at the end of a holiday you can do most of this yourself at home by following these easy steps:

Rust check

Firstly you need to have a look at your edges and get rid of any rust that might be forming. It can be easily taken off with a simple rubber or use wire wool for more stubborn patches. It’s important to catch rust early because it can spread if skis are left untreated for months over the summer. This can significantly decrease the lifespan of your skiing equipment making future holidays a pain to get prepared for.

Edge Care

For further care to your edges (and to save time in the shop at the start of your next ski trip) you could buy an edging tool; a small machine that is very good at smoothing out ‘burrs’ in the metal. If these little sharp dents are left they can become more pronounced so it is worthwhile to get rid of them at the end of every season if you can. You would only need to get this done once a year normally, but if you plan on having quite a few adventurous trips then it would worth the investment.


This is easier to get done in a shop and doesn’t cost much. If you have your own though then great, slap it on – it doesn’t need to be neat for storage as you can scrape it off to the right amount when you are ready to use them again. You can even just run a candle over the edges and put a piece of wax paper between where the bases touch for protection if you want to get them waxed properly at the start of the next season.

Proper ski storage

This is one of the most important tips which many people get wrong. Even if you don’t bother with any of the above, you should always make sure you store your skis properly in a clean, dry environment where they won’t get knocked about and damaged. The edges can oxidize and go rusty if they get damp and this can actually happen if you keep them in a ski bag, so as tempting as it is to put them away neatly, it is worth standing them up somewhere like the back of a wardrobe. Keep them together with a Velcro strap and it’s also and idea to turn down the release clamps to relieve stress on the cables. This means that the DIN settings will be exactly the same as you had them set before.

Ski Boot care/storage

Ski boots need to be thoroughly aired before they get put away for the summer. You can do this by pulling out the inners and stretching them out on a radiator (or outside if it’s nice weather). Once completely dry put the inners back into the shell and make sure you fasten the buckles up to how you normally wear them. This is really important as it will be difficult to do your boots up the next time you wear them if they are left open for any length of time. It is best to store them in a boot bag if you own one, or at least wrap them up in plastic bags sealed with duct tape.

Although all of this may seem like a lot to consider it is worth protecting your investments. Skiing can be an expensive hobby – so the more care you take of your equipment, the more cash you can spend on having fun on your winter holiday.


Best Places in the Western United States for Nordic Skiing

The Western United States is a hub of winter sports activity, but Nordic skiers from around the world travel here to experience perfect conditions, breathtaking views, and rigorous, varied terrain. Each state has its share of beginner, intermediate, and expert Nordic trails, and many areas offer backcountry exploration opportunities. No matter your ability or adventurousness, there’s a trail for you; if you’re heading out west in search of great cross-country skiing, you won’t be disappointed. Below, we have listed the best places in the Western United States to strap on some skis and explore the wilderness.


Soldier Hollow

Rated one of four top Nordic resorts in North America, Soldier Hollow is one of the most renowned cross-country destinations in the United States. This was the site of the biathlon and Nordic events during the 2002 Winter Olympics, adding an extra special feeling to the 31 kilometers of classic and skating trail and biathlon range. Located in Midway, Utah ad Wasatch Mountain State Park, the facility offers lessons, clinics, rentals, snowshoe trails, a tubing hill, and a lodge. Visitors can choose from both easy-rolling trails or Olympic-level courses, all of which are immaculately groomed. Though not the only Utah skiing opportunity (didn’t know domain for Utah Ski Authority) , Soldier Hollow is certainly the first place to stop.


Sequoia Ski Touring Area

With over 800 miles of trail, Sequoia & Kings Canyon National Park is a cross-country skier’s paradise. Located in the heart of Sequoia National Park, this is the perfect place to learn or hone your Nordic skiing skills. More advanced skiers are encouraged to try an overnight Nordic trip; though wilderness permits are required for all overnight trips away from designated campgrounds, this is a unique way to experience one of America’s most beloved forests. Visitors can purchase maps of ski trails online or at any of the visitor centers. Additionally, cross-country skis are available for rent at Wuksachi Lodge. California skiing already has a lot to offer, but there’s nothing like gliding through towering Sequoias.


Enchanted Forest Cross Country Ski Area

As New Mexico’s largest full-service cross-country ski area, visitors to Enchanted Forest can experience over thirty kilometers of wide, groomed trails of varying difficulty. There are five dog friendly trails, fifteen kilometers devoted to snowshoes, and terrain for all ability levels. These meandering forest trails are set against the backdrop of stunning mountain vistas, and—though groomed and patrolled—the ski area has a backcountry feel. There are several Yurts to take rests, and this area is located amidst some of the state’s best Alpine skiing—if you’re in the mood to switch it up.


Bohart Ranch Cross-Country Ski Center

Just sixteen miles from downtown Bozeman, this ski center is set within the serene and spectacular Bridger Mountain Range. All thirty kilometers of trails are impeccably groomed, and they remain open all winter, weaving through both scenic and secluded sections of the wilderness. The Center offers on-site lessons for skiers of all levels, and clinics are held for more intensive, personalized instruction. This is a great place to experience Nordic skiing if you’re in the area to experience the alpine thrills of Bridger Bowl.


Bear Basin

Bear Basin offers a trail system operated by the Payette Lakes Ski Club. With around thirty kilometers of groomed trails, these sinuous paths wind their way through the forest. Perfect for Nordic skiers of all levels, these trails are groomed for both skate and classic skiing. The area also offers after school programs, summer events, and lessons for every ability. Their mission is to provide an affordable, accessible, and sustainable winter recreation facility, and that’s exactly what they’ve done. Idaho may be known for its alpine skiing, but they have plenty of Nordic opportunity.


Yellowstone National Park

Yellowstone is one of America’s most iconic National Parks, and winter visitors love to take advantage of the incredible Nordic skiing opportunities. Cross-country skiing is allowed on all unplowed roads and trails, and there are several ski trails in the Mammoth, Tower, Old Faithful, Northeast, and Canyon areas of the park. Though Yellowstone may not have the frills of a standard ski resort, there are plenty of beginner and intermediate trails perfect for those just starting out.


Frisco Nordic Center

One of the Rocky Mountains premier Nordic ski destinations, Frisco is the first place we’d recommend for cross-country skiing in Colorado. The Nordic Center offers 27 kilometers of ski trails and10 kilometers of snowshoe trails. Daily trail passes are $15 for youth and $20 for adults. You can double these prices if you plan on renting skis from the center. Season passes, individual and group lessons, and plenty of events during a season that typically starts sometime in November and is in full swing by the year’s end. Beginner ski hills and tubing are also just steps away…..Find more places and information about skiing in Colorado.