Adjusting your saddle to work with aerobars
by Jamie Sarkisian

You've read articles and seen photos on how the saddle is positioned to work with aerobars. This article will help you adjust your saddle to work with aerobars. To start with anything else is like designing an automobile engine around a chassis. 

Figure 1 Good Aero Position,  (forward on seat)

Aerobars change the way your body is connected to the bike and therefore can have an effect on saddle position. With aerobars you tend to move forward from where you would ride with drop bars. Your body is connected to the bike by three points of contact; pedals, saddle and handlebars. When resting on aerobar pads the forces on the rider change slightly compared to drop bars. When riding, you want to assume a position on the bike such that the body is in equilibrium. If you are not in equilibrium on the saddle, you must compensate by pushing or pulling on your handlebars. It is best to be relaxed on the bike. and let your legs do the work. Figure 1 shows a rider in good aero position but the bars are pulling him forward; this may detract from what is efficient.

 

Figure 2 (Forces on the body)

Your saddle position can also be affected by other factors such as changing hand positions, moving the aerobars back, or raising the stem. These changes alter the forces on & body slightly. Ride in the aero position and lift your elbows off the armrests (figure 2). You will notice a tendency to slide back in the saddle, due to a change in force. When climbing, the force of gravity changes relative to the bike while you pedal harder. This explains why riders tend to move back in the saddle when climbing.

You should experiment with saddle position to find out what works for you. From my own experience, the seat height is more critical to rider power. Set up your saddle so you can comfortably move back and forth without significantly changing the height to the crank center. Ride forward for about I minute and then slide back for the same time. Pay attention to your pedal stroke and how it changes. If you can be efficient in both positions you will find that it is best to alternate positions in order to use different muscle groups for short durations. It's like standing out of the saddle for a quick jump, you generate more power but only for a limited time. 

The use of aerobars involves rotating your body in a forward direction. If you leave your saddle alone, the angle between your legs and your upper body may become too sharp. To compensate, you can move the saddle forward to increase the angle between your legs and trunk, Moving the saddle higher helps reduce stomach cramping. Saddle height is critical for performance but if too high will increase the likelihood of injury. Stomach cramping is reduced by raising the handlebars or pads, but here aerodynamics is sacrificed. 

Figure 3 Just Starting Out

When you first start riding aerobars you should not make drastic changes to your saddle, position. You might want to move the saddle forward a little to compensate for the now equilibrium position. This would position your saddle such that the nose would be about I inch behind the, bottom bracket. When the cranks are horizontal, the forward knee should be directly over the pedal center. this compensates for different leg sizes. For new riders, the aerobar position should be somewhat like Figure 3, with the back higher and elbows further apart.

 

Figure 4 Excellent Aero Position

More experienced riders should raise their saddle, narrow their hands, and narrow their elbows without constricting breathing. THEN POSITION YOUR ELBOWS SO THAT YOUR THIGHS DRAFT YOUR ARMS. Some riders am too stretched out so their thighs are not drafting their arms. Your thighs represent 140 sq. in. of area; The equivalent of about 8 water bottles. To make things worse your legs are moving! Thus making a slower cadence mom aerodynamic. If thigh area if removed could save about 10 seconds per mile. (too hard to pedal) But if properly protected by the arms one could save 20% or about 2 seconds per mile. (figure 4)

Positioning your aerobars

• Don't be so stretched out that you tend to pull forward on the seat

• Keep your hands in narrow and your back flat

• Keep your elbows in narrow without constricting breathing

• Adjust your position on the bars as you slide back and forth on the seat to maintain optimum aero position by keeping your elbows on the pads as close to your knees as possible.