Sunday, March 1, 2009

Calibration - about 20 watts too high...


So as usual the first principle of power meters applies... if it sounds too good to be true it probably isn't...

Anyway, first pass at it appears that the Ergomo with its factory setting k-factor of 196 is about 20 watts too high.

This is my standard PowerCalibration60.erg test, start at 100w and increase 1watt/second until you fall over. I usually last five minutes, which gets me to a load of 400watts.

The two power files get munged in an excel spreadsheet. The chart to the right shows the overall match.

I'm estimating that a drop in k-factor of about 20 will be needed. I'll do another test tomorrow with that.

Assuming that, adjusting yesterdays ride file makes the overall IF 0.988 (instead of 1.07), TSS 97.7 (drop from 112). NP 282 (previously 300). Much more believable... Right in line with current FTP of 285..

Give the cool weather, heavy training wheels, two water bottles, three layers of clothing, etc, I still believe that this could be an NP buster ride (one hour with IF > 1.05) ...  but unfortunately yesterday wasn't :-)

Today was an L2 ride from hell... Out around Ford Road... and just at the farthest point from home it started to rain... so the last hour and a half was cold AND wet.. So much for listening to the weather forecast. They said rain in the morning and clearing in the afternoon and evening.. So where did this rain at 4:00PM come from.

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