Analyze Wind?

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kq6up
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Analyze Wind?

Post by kq6up » Sun Jan 20, 2019 10:59 pm

The analyze wind feature is not really thoroughly explained in the instructions. What does wind offset do? The ground wind makes sense, but the changes it makes do not seem to be actually applied to the ride if one hits accept. Could someone clarify?

Thanks,
Chris Maness

Velocomp
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Re: Analyze Wind?

Post by Velocomp » Mon Jan 21, 2019 9:35 am

The Analyze Wind feature allows you to adjust the net ground wind speed of the ride. When you change the ground wind number the watts are adjusted accordingly.

Changes in this window affect the ride file only; it does not change anything in the profile.
John Hamann

kq6up
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Joined: Sun Jan 13, 2019 9:58 pm

Re: Analyze Wind?

Post by kq6up » Mon Jan 21, 2019 9:50 am

Thanks, John I got the ground wind, but what is wind offset? I see that it is a function of the other. In other words, I can’t make them both zero at once.

Thanks,
Chris

Velocomp
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Re: Analyze Wind?

Post by Velocomp » Mon Jan 21, 2019 1:55 pm

Wind offset is a calibration parameter from the very early versions of our products. Basically, when a device is at rest, in zero wind, there should be no wind reading on the device. Wind Offset allowed users with mis-calibrated devices (non-zero wind offset reported on their device screens) to correct that error.

With new versions of our products, and with the much-better sensors we are using now, this parameter is no longer relevant.
John Hamann

kq6up
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Re: Analyze Wind?

Post by kq6up » Mon Jan 21, 2019 11:38 pm

Thanks, John

Wobblydrow
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Re: Analyze Wind?

Post by Wobblydrow » Wed Jul 31, 2019 4:48 am

Hi

I have another question about wind. I get wheel speed - wind = ground wind, the question I have is , for example, today was riding into a gentle (5kph) wind yet the software says it was a tailwind, and picked up a peleton at around 40kph. As expected the software determines i was drafting, and the wind dropped from near to my wheel speed (40kph) to about 10kph, resulting in a negative 30 ground wind.

If i looked at this logically a negative wind would be a tailwind, but its not in reality, it was a slight headwind. So what exactly does a value of -30 ground wind actually mean? in this situation? Each time I have been drafting I see a big delta between wheel and wind, but its not a tailwind in actual conditions.

Secondly, is it correct to assume that if wheel speed is tracking with wind speed then its effectively saying its calm conditions? ....so if wind line is tracking below wheel speed(tailwind), and i acccelerate, shouldnt the magnitude of the wind change, as the closer you get to exceeding the tailwind speed, the closer the wheel/wind speed line should be, and eventually you would be travelling faster than the wind and reading a headwind, or am i thinking about it the wrong way?

Velocomp
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Re: Analyze Wind?

Post by Velocomp » Wed Jul 31, 2019 11:00 am

Please post a .ibr ride file that illustrates your questions.
John Hamann

Wobblydrow
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Re: Analyze Wind?

Post by Wobblydrow » Thu Aug 01, 2019 6:01 am

iBike_07_30_2019_0534_30_km.ibr
(208.85 KiB) Downloaded 4 times
Here is the file, have a look at 24 to 39 minutes, this was riding north west into a north/north west 5-8kph wind.

Velocomp
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Re: Analyze Wind?

Post by Velocomp » Thu Aug 01, 2019 8:41 am

Wobblydrow wrote:
Thu Aug 01, 2019 6:01 am
iBike_07_30_2019_0534_30_km.ibr

Here is the file, have a look at 24 to 39 minutes, this was riding north west into a north/north west 5-8kph wind.
1) Until minute 24 you were riding solo. Your ride file indicates a small tail wind; if this is incorrect you might want to do a new calibration ride

2) From minute 24-41 you were in a peloton. Wind speed was less than bike speed.

3) Even when drafting the total opposing wind speed is greater than zero. I graph total wind speed (as opposed to ground wind speed).

4) Yes, in calm ground wind conditions the blue wind speed should hover around white bike speed.
Attachments
Screen Shot 2019-08-01 at 8.35.43 AM.png
Screen Shot 2019-08-01 at 8.35.43 AM.png (156 KiB) Viewed 175 times
Screen Shot 2019-08-01 at 8.36.06 AM.png
Screen Shot 2019-08-01 at 8.36.06 AM.png (143.74 KiB) Viewed 175 times
John Hamann

Wobblydrow
Posts: 17
Joined: Mon Jul 29, 2019 6:29 am

Re: Analyze Wind?

Post by Wobblydrow » Thu Aug 01, 2019 6:01 pm

So when drafting and the wind effect comparison is used, and shows (say) net minus 25, it doesn't mean a 25 kph tailwind, it means the bike has an effective net benefit equivalent to 25kph tailwind.

I guess I wanted to know how to read that wind effect comparison correctily

Velocomp
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Re: Analyze Wind?

Post by Velocomp » Fri Aug 02, 2019 8:26 am

Wobblydrow wrote:
Thu Aug 01, 2019 6:01 pm
So when drafting and the wind effect comparison is used, and shows (say) net minus 25, it doesn't mean a 25 kph tailwind, it means the bike has an effective net benefit equivalent to 25kph tailwind.

I guess I wanted to know how to read that wind effect comparison correctily
Correct.
John Hamann

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