Ask the Experts: John Cobb - Part IV

John Cobb, bike fit and aerodynamics expert, recently took the time to answer Endurance Corner team member questions. We're sharing his responses as part of a series throughout the summer. In this installment, John answers some more questions about position and cleat placement.

EC: You mention going lower for more comfort on rolling/climbing courses -- this makes sense to me if I'm using my bullhorns as drops. However, a low base bar position (where my hands are low/forward relative to my hips) makes my standing climbing position less efficient. For long TTs with sustained climbs (low air speed), I find it effective/efficient to climb standing. That's why I've tended to use a simple, flat base bar with clip-ons. Could you expand on your advice about getting low for comfort?
John Cobb:A lot of riders want to look way down the road to see what's up ahead. While I feel you need to be able to see a little ahead, 50 to 60 feet should be plenty along with the occasional "sighting" up ahead. This takes the sharp kink out of the rider's neck. As you move more forward and as you rotate the pelvis to maintain good breathing, you need to go lower to keep the hip/torso angle the same. Most triathletes don't power up a sustained climb, they make good even power so breathing and comfort are more valuable.

EC: I'm a round-back rider; at what level (speed and/or power output) would you recommend that I consider moving more forward to get my back down. I can get quite aero with a steep/forward position but feel like I'm losing power versus my traditional slam-position (with round back).
John Cobb: You have to be your own judge on some things. Use a power meter and do back to back testing versus the speed and that will give you the answers. It takes a lot of power to offset small aero loses even at speeds of 15-17 mph.

EC: I noted your tip about going lower with saddle height and have noticed that Lance rides low. With a low saddle position, I can feel like I'm losing extension/power as well as closing off my hip angle. Any further tips for a rider that likes the slam-position?
John Cobb: We have never found any measurable loss of power from a lower seat height -- a high seat height happens to feel better in the parking lot. Seat heights that are too high cause constant seat comfort problems, strained tendons and toe numbness. Low seat heights help you run off the bike better and makes the rider's hamstrings more comfortable. If you feel that your upper body angle is pinching, go to shorter cranks. Anybody under 6'1" should really look at 165mm cranks for more speed and comfort.

EC: Do you have views about cleat width? I've shifted to a wide-stance cleat position on my bike this season as an experiment.
John Cobb: I don't have any real strong opinions about wide cleats other than as you widen the cleats your knees tend to fall in more toward the top tube. That can be good or bad depending on the riders ankle/knee/hip [real Q factor] alignment.

In case you missed it:
Part I - Bike Fit
Part II - Hilly Courses
Part III - Equipment Selection

John Cobb is a world leader in cycling aerodynamics and bike fit. He's based in Tyler, Texas and can be reached via his website (www.CobbCycling.com).