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Using the Apparent Wind While Riding in a Paceline
by Ken Rasmussen
Last month’s newsletter contained an article submitted by Ken Rasmussen on some of the finer points of riding in a paceline. Unfortunately, part of the article was missing, likely due to some sort of error in transmitting it to Anita, our newsletter editor. It’s presented here in it’s entirety.
Several weeks ago there was a piece written in this newsletter to help the riders in our club approach paceline riding in a similar and predictable manner. The intention was so praiseworthy that I have hesitated to criticize the article in its details. However I’ve been thinking about it a lot, and I’m concerned that some of the things that went unsaid in the article will create dangerous conflicts between riders who attempt to follow the rules listed in the article with other riders who have a more thorough understanding of paceline riding.
The problems in the previous article arise from a failure to consider the effects of the apparent wind upon the positioning of the riders in a paceline. What a paceline is, is a method employed by a group of riders to permit the group to power through the wind more efficiently and faster than the riders in the group could do separately. It is a team effort. It works when the members of the team make a conscious effort to work together AND when they share a common understanding of how to position themselves in a wide variety of wind strengths and directions. To that end, stronger riders have to restrain themselves from outdistancing less strong riders. Instead, stronger riders should take longer leads, and less strong riders should focus on taking shorter—sometimes extremely short leads. But all riders should commit to making the line work smoothly and safely.
For the line to work at all, every rider needs to understand how to shelter most effectively from the wind within the line. This means that every rider must understand the concept of “apparent wind”. If a cyclist is stopped, and they feel wind, that is the “true wind” that they feel. It has a strength and a direction. If a cyclist is riding in still air, they will feel a wind coming from in front of them. That isn’t true wind because the wind isn’t blowing. It is apparent wind that results from the cyclist moving through still air. When a cyclist is cycling in wind, the direction of the apparent wind is a combination of the true wind and the passage of the cyclist through that wind.
Let’s imagine, temporarily, that our cyclist is on a level, featureless concrete plain, cycling due north. In the absence of wind, the apparent wind is from directly ahead. In a wind from the north (a headwind) the apparent wind is still from the north, but it is stronger. Now imagine the cyclist moving at 15 miles per hour to the north, but the wind is blowing from the east at 15 miles per hour. The apparent wind will be coming from the northeast and it will be stronger than 15 miles per hour. It will be felt on the right side of the cyclist’s face, coming at a 45 degree angle from the direction of travel.
Now let’s consider the same situations, but with two riders. The two riders are going to alternate leads so that one rider can recover while the other breaks the force of the wind. In still air, thefollowing rider will be directly behind the lead rider. The same will be true in headwinds and tailwinds. To switch leads, the front rider will check for bikes or cars to their left, signal by pointing or an elbow flick to the left, move left and the following rider will pull through smoothly, without accelerating, and give the former leader an opportunity to pull in behind. After the following rider is in place, the new leader may accelerate a little, but gradually. Remember, the optimum group speed is the goal. If the leader drops the second rider, that’s a failure.
Now think about the crosswind situation. The riders are moving north, the wind is from the east. The apparent wind is from the northeast. The following rider will find their best shelter southwest of the leader. They will be able to optimize their position by moving fore and aft a little bit until they feel the most benefit from the shelter of the leading rider. This business of feeling the wind on the face and knowing where to move, and then subsequently optimizing the position by moving fore and aft is a skill. The more you do it, the better you will get at it. (I race sailboats with quite a bit of success. Knowing where the wind is, is natural to me. I can always spot racing sailors when they are cycling in a paceline. They know exactly where to be.) Winds can come from any direction at any strength. That means that occasionally the following rider will be cycling right next to, or even slightly ahead of the leading rider! The leading rider is actually the rider who blocks the wind—they don’t always lead.
Now we’re going to leave the imaginary concrete plain and go to a road. We recreational cyclists are often fascinated by professional riders. However there are some reasons why we shouldn’t always emulate them. Recreational cyclists ought to be prioritizing safety over all else. Professional racing cyclists prioritize victory over all else. They crash far too often. Recreational cyclists often work together to optimize the group effort. Professional racing cyclists work as teams or form temporary alliances, meaning that some cyclists are trying to help each other, and others are trying to hinder or exhaust each other. Professional cyclists race on closed courses so they can utilize the entire roadway. Recreational cyclists need to ride as far to the right as is practicable.
So, in the crosswind situation previously described, the professional cyclists form echelons—lines that snake diagonally clear from one edge of the road to the other. Recreational cyclists don’t have the entire road. They must (depending upon the angle of the wind and the road conditions) limit themselves to mini-echelons of two to four riders who keep to the right. If the group is larger than will fit in one echelon, multiple echelons must be formed. When the wind is from the right, the leader rides to the right to give the following rider(s) space to fan off to the left. At the end of their pull the leader waves the next rider through and drops straight back. When the wind is from the left, the leader rides to the left to give the followers room to fan back to the right, and moves straight back after waving the next rider through. (There are a couple of reasons why you should drop back on the same side that you lead from. One is that in a cross wind, wheels are often overlapped. Moving toward the other riders increases the likelihood of a lapped wheel crash. You could avoid that by speeding up and going forward to clear the next rider, but then you’d have to ride solo in the wind until you reach the back, and it’s the long way around. It’s safer and less exhausting to drop straight back in a cross wind.)
Overlapping wheels is a leading cause of cyclist crashes. One should never ride with closely overlapped wheels. However in crosswinds the good shelter is often in an overlapped zone. To ride safely it is important to have enough lateral separation between riders and wheels so that a small waggle by the leading rider doesn’t cause a crash by the following riders. It is the responsibility of the leader to ride as straight a line as possible, to signal obstacles, and to signal their intent to change direction or to slow down. (The right arm points right, the left arm points left. Don’t signal right turns with the left arm. The slow signal can be on either side. If I’m turning right I’ll use the right arm to indicate slowing and turning.) The following riders have a responsibility to ride straight and smooth, and to use good judgement in positioning themselves. All riders need to ride smoothly, predictably and to look around and ahead. There is a saying: “If you’re only watching the wheel in front of you, it will be the last thing that you ever see.”
In summary: Most recreational cyclists have a poor understanding of where to place themselves in varying winds. They don’t know where they need to be when leading, or which side to drop back on. I have often wanted to stop an entire group to explain it, though I never have. I hope that many of you will read and absorb this material, and then teach it to others. It would be worthwhile to find yourself a serious cyclist of about the same speed as you, and practice with just the two of you. Leave a generous gap between yourselves for safety. Constantly assess the wind direction, find the best shelter, adapt swiftly to changes in the wind direction and speed, changes caused by trees, barns and so on. When you ride with groups, assess the level of knowledge and expertise of the other riders in the group. Follow some people at more distance than others. Don’t follow bozos, or allow bozos to be ahead of you in a line. There’s nothing stupid about allowing yourself to be dropped from an unsafe line. Share the knowledge as much as you can. Ride safely.
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