I carried out a rough and ready turbo test to check Ergomo mounted on my fixed Langster vs Powertap on my Roubaix.
Protocol was pretty basic, I used my HR as a control and did 3 sets of 40 minutes each comprising:
A-Ramp up 100W-270W 10W per minute (so from rest through endurance to top of tempo zone)
B-Hold 270W 3 minutes (so to halfway through)
C-4 5 minute intervals at 260W/250W/240W/250W
Interval 1 was done on the Powertap, Interval 2 on Ergomo, Interval 3 on Powertap.
I chose this power range as I will mostly be using fixed for endurance/tempo riding so its the most important.
I reasoned that if the power was comparable the HR should be as well. During the intervals I kept the HR display off to make sure it did not influence me.
Results summarised in graph above. The first 2 intervals were remarkably similar, exactly the same in terms of power and HR was pretty much the same. Last Powertap interval was up a bit in terms of power and higher in terms of HR. Put the latter down to a bit of cardiac drift and the fact I started the interval 10 beats up on the first two.
Test could be improved and I could repeat with 2 Ergomo intervals and 1 Powertap. Nonetheless seems to show the two are pretty close.
