Drag Caused By Clothing

[82zman]

This time of year in Chicago I can be in either in a short sleeve jersey or my full winter gear which of course increases my drag substantially. When making significant changes to riding apparel, besides the obvious weight difference I assume I would need to do some coast downs, but what about the 4 mile calibration ride, would that need to be repeated? I am using the iBike Gen III Pro model.

[benlane]

My understanding from Boyd who has given me a bit of tuition on this subject says no need for the 4 mile ride, just new coastdowns. i gather the 4 mile ride sorts out wind scale and riding tilt.

I am sure boyd will pop onto this thread to confirm this.

[coachboyd]

Here I am!

Ben is correct. Wind scaling and riding tilt are stored in the unit. If you change clothing both of those numbers will stay exactly the same. The main thing that will change is your aero number.

What you can even do is manually change the numbers slightly in your profile. You will want to increase the aero number. This will keep wind scaling the same and increase your cda. For a reference point, my cda goes from a .318 in just a jersey to a .325 wearing a vest and a .336 when I wear a jacket and full finger gloves.