Pace Line 101: Drafting

by Jack Gregory

I started bike racing in college, which was, well, many years ago, and I was able to learn group riding with experienced people who really wanted company — it was before “Breaking Away”, and the long-time riders were very helpful and non-competitive with newbies.  The most important skill, by far, was learning to ride in a pace line.  A bad rider in a line could easily break or kill a good one, so there was a great deal of interest in training the new guys right.

The basic idea of drafting is natural enough; stay just behind another rider, and you will use about 15% less energy going the same speed.  At least, the wind-tunnel testing says 15%, but to me it has always felt much easier than that, maybe 50% or less.  I think it is psychological, or maybe just that the last 15% feels like 50%, but the point is, it is much easier to ride 20mph when you don’t have a 20mph (or 30) headwind.

The dangers of drafting are also obvious enough: you use even less energy the closer you get to the rider ahead, but your ability to react to that rider and the road goes down to nil.  At the limit, you are completely in the hands of the rider ahead; you won’t see road flaws and you won’t be able to react to braking.  One mistake, a wheel touch, and there is a good chance the guy in back goes down.  It is always the guy whose front wheel is involved that will go down.  If there are 5 riders in a line, and the second goes down, chances are the next few will as well.

The new rider should start drafting at a reasonable distance.  It has to be less than a bike length, but it shouldn’t be closer than 12 inches until you have lots of riding and lots of trust in the rider ahead.  Furthermore, you should always have a “way out”.  Always have a preferred side or offset, so that a sudden slowdown of the lead rider won’t cause a wheel touch.  But don’t ever “overlap” wheels on a continuing basis.  Passing is fine, as is a temporary overlap because of a slowdown, but get out of overlap as soon as possible.  Sitting six inches to the left, and six inches overlapped is a recipe for disaster.  The rider ahead moves out of the way of some street debris and you are kissing the pavement.

The preferred side is the one opposed to the wind.  If the wind is a little to the left, sit behind and slightly right.  This “echelon” formation becomes more important with more riders and strong wind.  But we leave that to a future installment.  In the absence of a noticeable wind, I tend to sit slightly right.  I can see road hazards more easily, and I find most people don’t ride far enough (to my taste) right.

The rider ahead obviously has a lot of responsibility.  They are not only setting the pace, but they are the eyes of the line.  They are responsible for holding their line (position on the road), signalling road problems (pedestrians, pot holes, glass, cars, stops), and above all, being smooth.  No rapid decelerations for any reason.  They are on the front, they have to predict the line, and make smooth transitions.  A bad stretch of pavement ahead?  Move out slowly, pass it, and move back slowly.  Generally, with just a couple people, the leader doesn’t have to worry as much as with a large group.  The second guy in the line can usually see the road almost as well as the first.  It is still necessary to be smooth, but not as important to signal every flaw in the road ahead.  Just ride the proper line to avoid the flaws, and the next rider will follow.

So, how do you do it?  You ride behind someone!  Here is how I learned.  The rider ahead sets a steady strong pace; strong enough that there is a good draft, and that you will really get tired if you are not in the draft.  Now starting from about a bike length behind, put yourself directly behind the rider ahead, and move out of the draft gradually.  Feel a difference?  Maybe not.  Now get a foot closer and do the same thing.  Repeat.  Eventually, you will feel the draft.  It is a pocket of turbulent air coming off the rider ahead.  Because it is turbulent, it isn’t striking you entirely head-on, and this reduction is what makes it easier to ride in.

With multiple riders ahead of you, the draft is large and powerful.  It is easy to go 35mph in a pack of riders going that fast.  Of course, someone in that pack is on the front, and paceline riding is all about sharing the burden of making the draft.  The draft itself is what makes bicycle riding a group thing; it is easier to ride with others.  And it is what makes bicycle racing more than just time trialing; the riders behind don’t do any work, but you can’t win a race at the back.