I did some zone 2 riding with the Chung method at lunch today. Negligible wind, pretty good day. Data seems pretty good for comparing.
Head "normal" is so a helmet like the Giro would keep the tail out of the wind. "Slammed" is trying to get the head down so I can bite my knuckles on the aerobars.
Below is just relative CdA, not absolute. I'm interested in the delta.
-Giant Pursuit mips road helmet, head "normal": 0.2623
-POC Cerebel, head "normal": 0.2524
-Giro Adv 2, head "normal": 0.2522
-POC Cerebel, head "slammed": 0.2496
I am not disappointed or surprised the venerable Giro Adv 2 did well against the POC in the head tilt it was designed for. What really surprised me was that the overall "spread" from slowest to fastest was only 0.01 from an aero road helmet to a TT helmet.
Sure, the "jammed" down head was faster with being 0.0127 faster from a road helmet.
Looks like at my power would be 0.7kph or .44mph. About 21sec in a 10mi TT. Extrapolating to 40k, that'd be about 45 sec.
I thought that would be more than that.
Head "normal" is so a helmet like the Giro would keep the tail out of the wind. "Slammed" is trying to get the head down so I can bite my knuckles on the aerobars.
Below is just relative CdA, not absolute. I'm interested in the delta.
-Giant Pursuit mips road helmet, head "normal": 0.2623
-POC Cerebel, head "normal": 0.2524
-Giro Adv 2, head "normal": 0.2522
-POC Cerebel, head "slammed": 0.2496
I am not disappointed or surprised the venerable Giro Adv 2 did well against the POC in the head tilt it was designed for. What really surprised me was that the overall "spread" from slowest to fastest was only 0.01 from an aero road helmet to a TT helmet.
Sure, the "jammed" down head was faster with being 0.0127 faster from a road helmet.
Looks like at my power would be 0.7kph or .44mph. About 21sec in a 10mi TT. Extrapolating to 40k, that'd be about 45 sec.
I thought that would be more than that.
Last edited by:
burnthesheep: Nov 24, 20 11:53