Originally Posted by
Hermes
IMO, field testing equipment for small changes in CdA is hard to do and subject to inaccuracies. If you test on different days, Rho (air density) will be different. The fastest conditions are low air pressure, high temperature and high humidity. I use the indoor track at Carson and hire ERO to use their program, equipment and sensors. ERO measures Rho at the time of the test.
I didn't even think of that. Density altitude was 1000 ft on Tuesday, and -100 ft today... Looking at the numbers that is worth almost .5 mph, which means even with just 4 more watts, today's time would've been closer to 40 seconds faster, not 7.
Edit: I'm going to keep testing the 38cm bars for a while. They are definitely different feeling, but not really less stable. Cornering and making power out of the saddle in the drops felt fine and staying tucked up / aero was easier on the hoods. 165 mm cranks come in today, hopefully I can have that ready to test for this weekend. I ran the loop in a more comfortable position and made 300w no problem, but tucked up 280-290 is difficult to average. If I can get the power back to just 300w while aero, then the time should drop another 20 seconds or so. It's also weird not having my old FTP. These numbers look so low lol.