Funky wind data this AM

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kq6up
Posts: 57
Joined: Sun Jan 13, 2019 9:58 pm

Funky wind data this AM

Post by kq6up »

Went out to measure the CdA of my commuter with the new firmware. I have been using AP on it by itself as a PM all this week with no issues. Ideal wind scaling factor for all my bikes with the sensor out in the clear. Added DFPM this morning, and showing 4mph tailwind the whole ride. Just to verify I did a 180 to make sure the wind was calm and it still read a 4mph tailwind. Needless to say the CdA was a crazy high unbelievable value of .995. I checked the Pitot for obstruction and to make sure it was secured firmly. I also checked the port for any dirt/debris— nothing. This is very discouraging. I experience this with my PP. That is the scaling factor changing wildly with no explanation other than component failure. I sent my PP in for this reason twice (it is on it’s way for wind sensor replacement now). This thing has been working great and verifying precisely CdA values I have derived by hand with roll down tests. I hope it is something simple, but not too hopeful as I think I have checked the obvious.

Chris
Velocomp
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Re: Funky wind data this AM

Post by Velocomp »

Please post the ride file
John Hamann
kq6up
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Joined: Sun Jan 13, 2019 9:58 pm

Re: Funky wind data this AM

Post by kq6up »

Ok. When I get back to the house. Hoping something goofed when I loaded the profile.

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

Re: Funky wind data this AM

Post by kq6up »

Ok, it looks like it loaded ok. Wind was dead calm, and in order to get the ride data to match I had to go from .973 to 1.71 on the wind scaling factor. Something is off, and everything I can think of I have tried.

Chris
iBike_03_10_2019_0815_7_Miles_HiDef.ibr
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Velocomp
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Re: Funky wind data this AM

Post by Velocomp »

Hmm...the temperature on this ride is much cooler than your prior rides.

We do a calibration procedure at the factory; I'm wondering if this procedure was done improperly on your unit.

Do a few more rides, hopefully at different temperatures. If calibration is the problem we can easily correct that at the factory.
John Hamann
kq6up
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Joined: Sun Jan 13, 2019 9:58 pm

Re: Funky wind data this AM

Post by kq6up »

My concern is that it is a big shift that I have never seen before. I have used it in near freezing weather, and it has shifted a little in really cold weather, but never .973 to 1.71. That is what my PP started doing when it started going bonkers all the time.

Chris
Velocomp
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Re: Funky wind data this AM

Post by Velocomp »

kq6up wrote: Sun Mar 10, 2019 7:27 pm My concern is that it is a big shift that I have never seen before. I have used it in near freezing weather, and it has shifted a little in really cold weather, but never .973 to 1.71. That is what my PP started doing when it started going bonkers all the time.

Chris
Well, I haven't seen it before either, and I've been using our devices for 15 years. Something may be different, we just yet don't know what.
John Hamann
kq6up
Posts: 57
Joined: Sun Jan 13, 2019 9:58 pm

Re: Funky wind data this AM

Post by kq6up »

Did an experiment. Switched to profile #3 and it is also misbehaving in warmer weather and the non variable CdA profile, so probably not a software issue with the new FW. Do I send it in? A wind scaling factor of 1.7 makes me believe there is now a hardware or blockage issue. The port and tube look clear tho, and I did not ride in any conditions that would have caused the port to become blocked.

Thanks,
Chris Maness
Velocomp
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Re: Funky wind data this AM

Post by Velocomp »

Actually, a WSF of 1.7 is within range.

Before sending in your unit, do some more riding. It is the variability, not the absolute value, that is concerning.
John Hamann
kq6up
Posts: 57
Joined: Sun Jan 13, 2019 9:58 pm

Re: Funky wind data this AM

Post by kq6up »

I set the WSF to 1.7 in the profile. It appears to be doing ok since it first shifted (no new shifts). It also seems to be tracking the wind ok at higher speeds. That was a big concern of mine (my PP had issues with this). If it shifts again, I will send it to you.

Thanks,
Chris Maness
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