Monday, July 16, 2007

Time Trial time estimating

I did a quick spreadsheet to compare times based on estimated CRR, CdA and power against previous time trial results. And got reasonably close results.

For the VeloVets 8k using CRR 0.004 and CdA 0.265 and adjusting the length for start and turn around times I got a finish time of 13:37. About 10 seconds faster than Saturdays time. But reasonably close. The actual time was probably slower due to the very slight amount of elevation gain, 17m; and the very slight wind (about 2-3km) in one direction.

For fun, using the same CRR and Cda (although most likely they where not quite as good last year) I put in the numbers for the Squamish TT from last August, using 280 as the average watts (as measured then with Polar). The numbers where amazingly (and most likely just luckily) close 54:47 estimated versus 54.42 actual.


TT Timing spreadsheet

The CRR, CdA and power numbers where crunched at Analytic Cycling to get the speed.

The CRR and CdA numbers where from the last wheel testing session and crunched using Alex Simmons spread sheet:

Excel spreadsheet
Google Docs Version

0 comments: