Originally Posted by FlashBazbo

Last weekend, I did the cycling segment of an area triathlon (relay category). To my surprise, after I had racked my bike, a guy I've ridden with before walked up to his bike which was racked next to mine. I had a pretty good idea he was going to beat me. Although my team won the relay, he beat me by about 5 minutes in the cycling leg. The differences:

I'm a relatively big guy (5'10", 174 lbs) with 46cm WIDE shoulders. I rode my BMC Teammachine road bike with 25mm deep aluminum climbing wheels and no aero bars. Bibs and jersey. No shoe covers. No shaved legs. No coaching. I rode in the drops the whole way.

He is a relatively smaller guy (@5'6", 135 lbs) with 39cm narrow shoulders. He rode a full aero Tri bike with a full disc rear wheel and a 90mm deep front aero wheel. Even taped up the inflator hole in the disc. He wore a skin suit, a TT helmet, and shoe covers. Shaved legs and arms. Lots of coaching on his bike position. He rode on the extensions the whole way. Smoked me.

After the race, we looked at our power data. I figured he must have averaged 70 or 80 more watts than I did. At the end of the day, looking at our respective power files, his average power was higher than mine . . . by just one (1) watt!

Even if you assume a MASSIVE margin for error, I'm going to take this experience as pretty strong evidence that aero really matters . . . a lot. My wide body will never be as aero as his narrow shoulders. He will always be more aero than I am. But equivalent equipment would surely have erased a lot of the difference.