I wonder if his PM is calibrated on the low side. Some STers seem to have this as well - they put out like ridiculously low wattage for speed despite being normal range weight/size, and their power seems very disproportionately low also stacked up against their run performance.

Andrew Coggan will soon be quoting Colby Pearce wind tunnel data from Texas A & M tunnel in the 90's. One thing is for certain, Colby Pearce has always been extraordinarily aerodynamic.

Pretty interesting article with some interesting points....

"
PEZ: How about watts?
This one will shock your readers: I averaged 251W. Not a typo. What needs to be explained is that I rode a very wave like pattern during the effort: I was riding 270-290w in the corners, and 220-240w in the straights. This meant my average was lower than my FTP (functional threshold power) but I was maximizing my speed. I was completely shattered at the finish, so riding at my FTP or not, it was what I could do in the ride. Obviously, I am a pretty aero rider."

It's also at altitude. I think MTM averaged barely over 300W? I'd imagine Colby's FTP in ideal testing conditions is closer to 400W than 300W.

Also riding an hour on the track is just really, really hard. I have no problem doing it on the road. The track can just get brutal. You don't realize how important those occasional 3-4 seconds of freewheeling through turns, etc, are until you don't get to do it anymore.

I wonder if his PM is calibrated on the low side. Some STers seem to have this as well - they put out like ridiculously low wattage for speed despite being normal range weight/size, and their power seems very disproportionately low also stacked up against their run performance.

Altitude is worth ~5-12% I think not 25-33%

I'd imagine Colby's FTP in ideal testing conditions is closer to 400W than 300W.

The followup question then should've been "What was the Normalized Power?" ;-)

Colby only averaged 300 W (+/- maybe 5 W) when he set the US hour record in the mid-1990s (at similar altitude).* Given that he is now a couple decades older, 250 W makes perfect sense.

Remember, he is significantly smaller than the average male cyclist, and quite aero (i.e., CdA of 0.19 m^2 even when using drop bars).

The other thing he had going for him is track-riding skill. Compared to others who rode the same block of days, he was machine, always glued to the black line. It was the same when he and wife trained together in LA in 2007...he could comfortably ride only a couple of centimeters off of her rear wheel, never wavering.

Finally, once upon a time I analyzed some data for him, from experiments he had done trying to determine the best approach to applying power on the track. I could not definitively say what was best, but obviously he is still a believer in "power the turns and float the straights".

*At the time, his VO2max was just over 70 mL/min/kg, with his LT being ~75% of VO2max. His cycling economy/efficiency was good, but not exceptional.

A *rough* estimate is ~0.17m^2. I've seen track CdA in that range before. Some people are aerodynamically gifted.

I wonder if his PM is calibrated on the low side. Some STers seem to have this as well - they put out like ridiculously low wattage for speed despite being normal range weight/size, and their power seems very disproportionately low also stacked up against their run performance.

The effort level was much harder on the 250m track than the two test hours I rode at Hellyer (335 meters). Night and day really.

If it's that much harder on 250m, then wouldn't CO Springs be better?

Makes sense that the air density is a little higher, but you are in that zone where it hardly matters... especially for someone who isn't acclimated. And if negotiating the turns is that big a deal, then it should be beneficial for someone with minimal track experience. Would it be enough to offset the slightly higher Crr?
If you haven't seen Pearce's ride, he was incredibly smooth. Obvious that he is very at home on the track.

Wheel speed and cadence rises in the bends for the reasons you describe, but surely KE can remain constant at isopower and torso speed sees much smaller fluctuations? It's not the same as similar cadence fluctuations on a straight TT, more like getting 4% wheelslip if you rode on muddy patches intermittently vs tarmac.
Relatively straightforward to calculate torso velocity for known wheelspeed on the black line, has anybody attempted to verify actual energy transfers?
My velodrome experience is limited to just scraping under 5 minutes for 4k pursuit.

dontswimdontrun wrote:

I think that the catch is that you don't get to make a U-turn at 30 mph for free. I think that the geometry of the track makes it very low cost compared to say turning around a cone in the road, but still not free. When I was testing gearing at Aguascalientes I wanted to run a 53x14. That was a good gear for the distance I was looking for, but it felt too heavy on the straights after going through the corner. After getting what felt like a free assist through the corner, hitting the straight felt like I was on a 1-2% rise. I realized that I couldn't handle 60 minutes of that and switched down to a 52x14.

BTW, here is a video of Colby's hour. It should be cued to his start, but if not scroll forward to 35:00.

---

Kevin

http://kevinmetcalfe.dreamhosters.com
My Strava

I think that the catch is that you don't get to make a U-turn at 30 mph for free. I think that the geometry of the track makes it very low cost compared to say turning around a cone in the road, but still not free.