Wind way out

Post Reply
wormscoffer
Posts: 39
Joined: Fri Aug 05, 2011 8:06 pm

Wind way out

Post by wormscoffer »

Hello

Would someone be able to look at the attached file and tell me why my wind measurements are way out? I think the power is inaccurate as a result. I'm sure I held a fairly consistent power over much of the ride as I was using the gears to keep effort as consistent as possible.

Here's my route :

http://connect.garmin.com/activity/402398631

The wind was South Easterly (so I had a tailwind for about the first 22Km and a headwind for the last 18Km or so) and I'd estimate about 20Km/h with some gusts.

Elevation and slope look OK. Drafting doesn't look too far out but I know I wasn't doing any for the first and last 12Km as I was riding alone.

TIA

Andrew
Attachments
iBike_10_11_2013_0835_88_km_[AJH].ibr
(1.02 MiB) Downloaded 342 times
wormscoffer
Posts: 39
Joined: Fri Aug 05, 2011 8:06 pm

Re: Wind way out

Post by wormscoffer »

2 weeks and not a single reply.....hmmm.

I'll send an email to support then.
Velocomp
Velocomp CEO
Posts: 7793
Joined: Fri Jan 11, 2008 8:43 am

Re: Wind way out

Post by Velocomp »

wormscoffer wrote:2 weeks and not a single reply.....hmmm.

I'll send an email to support then.
Sorry, I missed seeing this one.

Your Wind Scaling Factor is unrealistically low; .19. The result is that you have a constant tail wind. I don't know how why this factor would be so low.

You can do a "check calibration" to get a more reasonable factor. However, I would also do a new Cal Ride.
Attachments
Screen Shot 2013-11-25 at 7.02.51 AM.png
Screen Shot 2013-11-25 at 7.02.51 AM.png (29.31 KiB) Viewed 4663 times
John Hamann
rstrom
Posts: 206
Joined: Wed Mar 24, 2010 1:02 am
Location: Chandler, AZ

Re: Wind way out

Post by rstrom »

One thing that I would add to this would be to go out and do an out and back ride (ride out and then ride exactly the same way back) and then use the Analyze / Check Calibration functionality in the Issac software.

In calibrating the Newton to my newest bike I did an initial calibration ride (which kinda sort of works but it has never been a good end result for me) and then did two or three of these out and back rides and ran the Analyze / Check Calibration function against the ride file after each out and back ride and accepted the adjustment.

After doing this a few times I then check my rides using the Analyze / Analyze Route function to see what the difference is. The resulting analysis is very close to the same as the downloaded file. The difference is virtually always a watt or less (maybe just over a watt every once in a while).

I have never, ever had more consistent power readings than I have had since using this method of calibration!

It's been stated in these forums at least a few times and my personal experience is that it is the way to go. YMMV.

HTH,

Robert
Post Reply