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Making a SkiMo Tow Rope
When I started researching techniques for partner skimo racing, a common theme emerged: lots of winning teams use a towing system to attach the partners to each other. I had an inkling that this happened because my Camp Race 260 pack had come with a tow system built in. Still, it seemed silly. However, as I though more about the psychological and logistical difficulties of racing with a partner, who no doubt possesses different skills and strengths, the potentially massive benefit of a tow rope became clear to me. In this post, I explain the pros and cons of using a tow, how to make one for yourself, and how to use it. For those not familiar with a rope tow, the system is simple: A length of elastic material connects the back of one racer to the front of another, usually with a carabiner-style attachment.
Purpose: Why Use a Tow Rope
The primary use for a tow rope is to help to average out the pace and fitness of partners. Without fail, one racer will be better on the climbs, or stronger at longer distances. By using a tow rope to remain tethered to one-another, the team is able to work as an average of their abilities. Without a rope, the team must travel at the pace of the slower partner (many partner races exact penalties for excessive distance between partners). With a tow rope, the stronger partner is able to assist the slower partner, and the team moves together at a pace faster than they would otherwise. The rope can also provide some physical assistance to the slower partner, offering a tug uphill or across the flats to make their effort less.
Perhaps an even bigger advantage to the tow rope is that it maintains a good psychological relationship between partners. Feeling like you’re the weak partner who always falls behind is demoralizing. Worse still is the inch-worm technique, wherein the faster partner runs ahead, stops, and waits for the slower partner, leaving as soon as they arrive. The faster partner gets no rhythm, and the slower gets no break, physically or psychologically. In my experience, when ski partners feel like they’re falling behind or can’t keep up, this paradoxically makes them slow down and has the nasty side effect of making them hate the faster skier. The tow rope makes the connection between partners tangible, allowing you to move as a team. With at most 20′ between one-another, you can communicate easily, make decisions, and maintain a good relationship through mentally and physically stressful times.
A third use for the tow rope is to prevent partners from being separated in chaotic mass starts. ISMF rule forbid the use of a rope tow within the first 15 minutes of a race, but this rule doesn’t apply to many North American races. In the Power of Four or the Grand Traverse, for example, starting the race on tow can prevent partners from becoming separated. No time is wasted locating your partner for the rest of the race.
Uh-Oh: When Not to Tow
The tow rope is not always useful, and in some situations it should not be used because it creates a hazard for the team. The most common hazard facing teams on-tow is long downhills. If a downhill portion is long enough to warrant removing skins, then the tow rope should be removed as well so that partners do not pull one another over while skiing or catch the rope between them on obstacles like trees. Visualize that: not good.
Additionally, the tow rope should not be used when in terrain that is more safely traveled with greater distance between partners. This includes avalanche terrain which necessitates safe travel techniques, in areas where rockfall may be possible, or on glacier, where snow bridges are a hazard. (A 30 m semi-elastic 8mm system can be used on glacier, but that is beyond the scope of this article.)
If there is any doubt, reserve the tow rope for use on rolling terrain, flats, or uphills, which do not represent a significant avalanche hazard.
Making a SkiMo Tow Rope
The good news is that it takes about $5 and 10 minutes to make a rope tow.
– 8 Feet of 1/8 – 1/4″ elastic cord
– 2 medium-size non-climbing metal carabiners
Both of these materials I bought at my local outdoors store. Hardware stores and army surplus outlets are also good options. Total cost of material was under $5.
To construct the rope tow, simply tie and overhand on a bight on each end of the elastic cord. I found it useful to make the loop on the end as small as possible, so that it held the carabiner snugly and didn’t allow it to rotate. Don’t worry too much if you have a little or a lot of tail on your knot; the elasticity of the system makes the lengths approximate.
There are no reliable published stats on bungee strength that I could find. The breaking strength of 1/4″ bungee is likely around 200 lbs, 1/8″ around 100. In our tested version, 1/8″ cord was used and my girlfriend was able to tow my 160#+gear frame from a standstill on flat ground with skins on without breaking the cord. It looks flimsy, but its not. Worth considering is that as the diameter of the cord increases, so does the force required to stretch it. 1/2″ cord will transmit a more aggressive tug to your partner than a thinner cord, which is not ideal.
I plan to continue using the 1/8″ cord and will update this post should it break. For confidence, you might prefer 3/16″ or 1/4″.
Using a SkiMo Tow Rope
The tow rope is tiny and easily stores in a pocket for quick access. It is easier if the team anticipates which partner may require the tow, as that person should carry the tow rope.
To deploy the tow, the tow-ee can unravel the cord and attach both each end to their partner and themselves respectively. The lower and closer to the hips that the rope can be attached, the better. The choice for the follower is simple: just clip the bungee around the waist belt webbing of your pack. I can’t recommend the use of belt-loops, unless you have some sort of Metolius safety-pants that are yet to hit the market. A better choice for the front partner is a low strap on the backpack, preferably centered. In our testing, using the back end of a side compression strap didn’t cause excessive rotational force on your partner, so that’s an option as well.
The use is then intuitive: the greater the difference in pace between partners, the more force is applied against each. The idea is not to completely drag your partner, but to give a gentle assistive pull. At full elongation, this provides about 20′ of space between the partners, which allows you to navigate switchbacks etc without excessive complication.
When coming to a transition which requires disconnecting the tow, either partner can detach the rope, though it is somewhat easier for the rear partner to make this maneuver. The cord can be left half-attached and either wrapped around the waist or stuffed into a pocket for quick deployment when the team again wishes to move together. Savvy teams might pre-rig the cord in this way before the race for faster deployment.
Tow Rope Beyond Racing
There you have it, the essentials of the tow rope for ski mountaineering racing. As with many things, this technique has trickled down from the glacier-traverse races of the European alps into our naïve North American hands.
I think that it can trickle down further: with such low cost, trivial weight, and supreme usefulness, I predict that the tow rope can be a useful tool for the average backcountry skier. My girlfriend thinks that it will help to preserve our relationship, and I agree. In any ski touring group there are those who will travel more slowly or need a little help. Being able to travel as a team during long approaches, across flats, or up valleys will improve overall speed and keep good relations between partners.
I, for one, will have one in my touring pack.
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