Wednesday, November 14, 2007

Orbea FTP Test

Last Tuesday was a 45-min FTP test on the Cervelo in TT position on the computrainer -- average 251 watts.

This Tuesday was a 45-min FTP test on the Orbea in road position on the computrainer -- average 274 watts.

That's a 9% difference and realistically probably 10% becasue I was fresher for the TT ride. That's about the difference that I expected between the two bikes/positions. The Orbea ride was also paced much better and I felt much more powerful throughout the test. It wouldn't surprise me if my TT ride wattage next Tuesday is higher due to better pacing alone.

The unexpected part of the whole deal was finding out that my computrainer wattage is 10% higher than the wattage measured by my Ergomo (mounted on my Orbea). I'm confident that my Ergomo is accurate, and this confirms a 10% difference between the two that I found last week when testing a teammate. I thought maybe his left leg was weaker due to a prior injury (which would result in an Ergomo/CT discrepancy), but I guess not. You'd expect the computrainer number to be a little less than the Ergomo number (maybe 2-4%) because of drivetrain losses between the crank and the road, but not 10% different.

All of my Tuesday night FTP tests will be on the computrainer but not always with the Ergomo, so I'll use CT numbers in my winter-training tracking charts. Measuring change is the important part, not measuring accurate wattage. Plus using the CT numbers will make me look stronger than I actually am, which is always a bonus!

Bottom line: My road FTP is about 265 now. Hopefully when I test in early January it will be at least 280.

1 Comment:

Scott said...

I think you mean 265 and 280.