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Isaac detects drafting when no actual drafting

Posted: Wed Apr 29, 2015 5:26 pm
by GeorgeHotopan
Hello everyone:

I believe this topic was somehow discussed in other threads, but just to make sure I attach a ride file I did today and explain myself.

It is a solo ride, NOT out-and-back, but it ended where it began. The original file (if analyze and return to original option is used) marks an average power of about 136W if drafting is checked, as the Isaac pop-up window suggests. Nevertheless, comparing this ride with other rides I did on the same course, the wattage is about 30W lower than expected. If I uncheck drafting box, then average power jumps to a more reasonable figure of 164W.

Could anyone double check the file and confirm that I should uncheck the drafting box. Why does Isaac believe I was drafting when I actually wasn't? Waiting for valuable feedbacks!

Best regards,

George.

Re: Isaac detects drafting when no actual drafting

Posted: Wed Apr 29, 2015 8:17 pm
by racerfern
If Isaac sees a period of time with a substantial tailwind it will assume you drafted.

I personally have no boxes checked and I enter my own starting and ending elevation. The results are absolutely consistent and repeatable.

Re: Isaac detects drafting when no actual drafting

Posted: Thu Apr 30, 2015 4:04 am
by GeorgeHotopan
Thanks for the explanation Fernando! Your feedback is always welcomed ;)