At the elite level, every small tweak to a ski, boot, or binding setup can be measured, felt, and appreciated. In the quest for speed and performance, all options are explored and tested. What to do with boot cuffs and cuff alignment is one of the small steps that is often misunderstood, ignored, or improperly adjusted, but it has a direct correlation to overall alignment of the leg and boot and will dictate a ski’s response on snow.
As current U.S. Ski Team athlete and 2015 national super-G champion Drew Duffy says in reference to cuff alignment, “My boots have never been so dialed in. I can’t believe what seem to be such minor adjustments could be so beneficial for my skiing.”
Each boot brand offers some form of cuff bolt and associated asymmetrical washer/housing system to hold the upper and lower shells together at the ankle pivot. Each brand has its own mechanical hardware, but essentially they all function quite similarly. Basically, you can adjust the lateral angle of the upper cuff, or “tip” it in or out, independent of the lower boot shell and sole. In the best case, this range is equal to 0.5-1 degree, +/-, of the lower. Over time, this pivoting mechanism has evolved to offer multi-directional or “compound angle” range of movements, whereby the upper cuff is not only tipped single dimensionally to one side or another but can be pivoted to the side AND towards the big or little toe direction of the boot. Pretty cool!
Our legs come in a variety shapes and sizes. Boots come out of the box with a stock angle, and more importantly, upper cuffs are set up consistently in line with the same angle as the lower shell. The soles of modern race boots can be 90-, 90.5-, or 91-degrees – essentially straight up or tipped just barely out. A simple visual observation of an athlete standing barefoot on a footbed out of boots with legs and feet hip-width apart can yield a picture of the legs coming up from the ankle at a certain angle. Sometimes the lower leg looks “neutral” or parallel, but other times the lower leg looks different than the angle inherently built into the boot. Common terms used to describe this variant anatomy type are “bow-legged” or “knock-kneed”. The goal of effective cuff alignment is to match the upper cuff of the boot to these variances in leg shape and angle.
BUT WHY BOTHER?
I believe this is important for two reasons. First, the legs of developed athletes are strong and disciplined in their stance. Depending on the space around the leg in the upper cuff, once the leg is strapped inside the cuff with a liner between shell and leg, you may have an issue where the leg interacts with that cuff in one spot sooner or with more pressure than the rest of the leg. The result will push a boot cuff away from the spot that has the most contact while tipping the whole boot sole with it. Second, as the leg travels fore and aft through flexion and extension movements, it guides the pressure along an axis in line with the ski tip. If the cuff is inconsistently pressured or the leg wants to travel in a different direction than the cuff (because of mismatched spacing), the boot will drive wherever that leg directs it.
Before any lower boot sole canting should be considered, this critical five-minute step should be taken. A proper, neutrally supporting footbed is the first key to the whole alignment process, so start here if that element is currently missing.
Remove the footbed from the liner, and drop it into the empty boot shell. Have the athlete step into the shells and lightly close the upper buckles to approximately the same settings used when liners are in. No need to do up the power or Booster strap. Adjust the width of the athlete’s stance using the same method as when performing a traditional alignment analysis or drill. With ankles slightly bent and the leg shaft floating inside cuff, visually inspect for consistent spacing around the leg as it corresponds to the cuff. Hopefully, there are equal gaps in all areas. But, you may find that one side of the leg is much closer to one cuff wall than the other, indicating our earlier terms “bow-legged” or “knock-kneed”.
You may see a bias to the outsides on both boot cuffs or a clear lean to the insides. It may be both legs consistently or it may be one leg, just a bit more than the other, due to anatomy differences, injuries, etc. Make note as to which direction you need to move the cuff, in or out, to match the same spacing around the leg. Next, have the athlete slowly drive leg shafts as if pressuring the boot during a turn, and note where the shins intersect the front of the boot overlap. There is never an ideal, but try for contact at the center or a hair inside of center as you can imagine that will translate to the inside tip of the ski. I made mention of “compound angles” above. The direction a leg travels during flexion and extension movements can be inconsistent or multi-axis. Legs can start inside and drive out, or come from the outside and fall in. The cuff hardware that allows some dual-directional adjustments will come in very handy for such anomalies.
Take the manufacturer’s tool supplied with the boots, and loosen all side hardware and spine bolts. Note the ranges on the ankle hardware. Most brands have these limits stamped on the cuff or parts, showing a “+ or -“. Plus means outside of center line of lower shell, and minus means in from center. These pieces are asymmetrical. If you move one towards a setting, you must move the other side towards the same setting, which will work together to push and pull the cuff in the desired direction. Moving just one piece, or one piece to plus and one to minus, will not effectively do much. Once the personalized adjustments are made, tighten the hardware back up and repeat the stance drill looking for space changes and directional leg drive. Once consistent and in line, tighten and test on snow. You can now also proceed to boot sole canting assessments and see if additional sole correction may be needed. My experience shows that lower shell canting will be different and often less following cuff adjustments. It goes without saying that a trusted performance boot fitter should look for and help you understand these mechanics and adjustments.
Watch the video below for a run through of the processes explained so far:
This step in the setup process is so often overlooked. What often ends up happening is boot fitters or coaches rack their brains trying to test canting on the sole to correct an under- or over-edged boot. No matter how many degrees they adjust from the sole, the results rarely change the reaction on snow. Separating the upper and lower cuff assessments and independently adjusting one versus the other in proper order will usually minimize what needs to be done under the sole for canting because the tension of the leg directing the boot in or out is diminished. It’s never a huge correction by limits of most hardware, and it doesn’t need to be. But this small step can go a long way in overall performance. After all, you bought the boots and they come with the parts. So you might as well try them!