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compensating for wind resistance

Posted: Mon Apr 13, 2015 6:02 pm
by mxfarm
Just curious how the iBike takes into account wind resistance of different sized riders. Not meaning weight - but width. IOW, if a rider is 23" wide @ the shoulders vs one 19" wide & they are both on a flat @ 20mph wouldn't the 23" rider be producing more watts to maintain that speed? Or are the speeds to low to effect the required power to needed to produce those speeds.

Re: compensating for wind resistance

Posted: Mon Apr 13, 2015 6:35 pm
by Velocomp
Most likely the 23" wide rider is heavier than the 19" rider. We use body weight in proprietary algorithms to help estimate CdA. This is something we learned after the first 3 years of reviewing coast downs, which actually measure the CdA, but are a pain to perform.

Re: compensating for wind resistance

Posted: Tue Apr 14, 2015 9:00 am
by mxfarm
That would mean the estimate would be all 240 lb riders would have the same wind resistance. It sounds like a rider outside the norm would could benefit from down coast downs - is that correct?

marc

Re: compensating for wind resistance

Posted: Tue Apr 14, 2015 9:58 am
by Velocomp
It's possible, but not likely, there would be a material difference. Most people are built about the same way.

Coast downs will work, but they need to be done carefully. If you decide to go that route read the Newton Instructions and follow the instructions completely.