Ever watched a downhill ski race and wondered how that racer gets such great performance and control from their boot? They achieve it by having not even millimetre of spare space in their boots because they have crammed their feet into a hole that is too small.
Race boots have one point in life – to be fast. They are designed for maximum feedback and performance. They are not designed to be comfortable. They’re built to be skied for 3 minutes at a time at up to 130ish km/hr. They have a thick shell that is fairly uniform with extra thick walls in areas of increased force. They’re known as a plug boot.
Race liners are thin and quite dense, they should be put on in the following order: place foot in liner, lace up liner, squish foot and liner in shell, buckle to the maximum tension achievable.
Retail ski boots (this covers ski boots for the rest of us mere mortals that make up the remaining ski world) are designed for a balance of control and comfort. This group of boots covers alpine ski boots, alpine touring boots, beginner boots, performance boots, and whatever else you can think of it.
Each boot and each skier is looking for a different balance between comfort and performance. Retail boots can be super light, have extra functions such as walk modes, and relatively cushy, or even fluffy, liners. The width of these boots is between 98 and 103mm across the forefoot at a size 27.0.
Fitting race boots is obviously quite different. Fitting retail boots is all about creating the gross geometry needed by using the bootfitters go-to activity – the expansion. Once this shape is made, the liner is typically heated up and does its best to mould to the foot shape of the wearer. Most retail liners are heat mouldable to a degree and do an okay job of moulding to the foot in question.
Race boot liners do not mould, they are super thin – usually around 4 to 5mm. Race boot shells are an average of 8 to 9mm thick. Fitting race boots is about grinding the details of the skiers’ foot out of the inside of the shell. These boots are closer to 92 or 93mm wide inside- not enough room to fit a foot, so it’s always going to be crammed in. A good boot fitter will use a Dremel-like tool to grind out bony points on the foot to at least represent the shape of the foot if not the volume. Expanding plug boots is inaccurate and a bit of a hassle – the thickness of the plastic makes it prone to returning to its original shape. Expanding also lacks the accuracy most racers require from their boots.
So next time you watch a ski racer, consider the squishy foot shape and discomfort she’s putting up with to achieve those edges. It’s always give and take with boots.