Analyze Wind

[carstenj]

When I select "Auto Analyze" for a ride file and afterward navigates to the detailed tab and select Analyze Wind then I see a field at the bottom called Wind Offset. This field always have the value -3.2 and I am wondering what it means and where it got that number from?

[travispape]

One of the functions that auto analyze can do, depending on how you have set the options, is to adjust the wind offset to modify the wind speed for the ride. That is what is happening in your case. You probably have wind adjustment set to "Adjust Automatically" under the "Options..." button. When you did the auto analysis, iBike2 adjusted your wind offset in order to make your wind speed more closely match your wheel speed. Ideally, you would end up with a wind offset near 0 after the auto analysis. Your relatively small correction to -3.2 means your wind offset calibration was probably a little off for the ride that you did.

[howard]

Travis,
If I ride at 16 mph into a 12 mph headwind why should my wheel speed and wind speed be about the same? Would not a wind speed of 28 mph be expected?
What am I missing?

[travispape]

Travis,
If I ride at 16 mph into a 12 mph headwind why should my wheel speed and wind speed be about the same? Would not a wind speed of 28 mph be expected?
What am I missing?

You're not missing anything--the auto analyze feature does not work well in all situations and certainly not in the scenario you bring up. However, the scenario you bring up isn't all that common for most riders.

The automatic wind adjustment works well for people who struggle getting their wind offset calibration correct. It also works pretty well for people who ride in a group ride. Idealy people would use the wind adjustment interface in the detailed tab and would take the time to understand how to use it (http://www.ibikeforums.com/viewtopic.php?f=6&t=255), but the automatic adjustment is available for those who want it. The best thing to do is get a good wind offset cal with the iBike stabilized to riding temperature and not worry about it.

[rruff]

The best thing to do is get a good wind offset cal with the iBike stabilized to riding temperature and not worry about it.

Yup... I can't think of any good reason to adjust your wind in iBike2, unless you *know* that it was an out-back or loop course in which the wind was very consistent. And then if it is off significantly and your wind offset was good, you will need to adjust your wind scaling so it will be more accurate on subsequent rides.