Wind Scaling difference in Newton and Isaac?

[NorBike]

Any one else noticed the Wind Scaling difference in Ibike Newton and Isaac after a Cal Ride?

Example:
If I do a cal ride the Newton calculate the Aero = 0,342. If i take take the same cal-ride file and look at it in the "check calibration" window, my Wind Scaling was 0.725 (Aero 0.283) before the cal-ride. The check calibration reports new wind scaling to be 0.714 (Aero 0.278).
BUT, the ibike shows a 0.342 aero, and if I extract the numbers from the next ride file after a cal-ride i see that the wind scaling is 0.877
So, I have two different wind scale/aero numbers from the same Cal-Ride. Ibike says Wind Scaling = 0.877 and Isaac says = 0.714.....

[Russ]

NorBike,

It would help to upload your cal ride file and your ride file for people to analyze.
I may not have time for next few days but maybe some one else will sooner.

Regards,
Russ

[travispape]

Any one else noticed the Wind Scaling difference in Ibike Newton and Isaac after a Cal Ride?

Hi NorBike,

Today I'm taking a look at the Isaac code for the Check Calibration function. It would be helpful if you could send me your cal ride that produces this issue to that I can look into it. You can either attach it here or send it to me at tpape at velocomp.

[NorBike]

I find this issue in all my cal rides, so my guess is that this can be found in other files too.
My example:
WS 0.725 and aero 0.283 before the cal-ride, and Isaac says WS 0.714 and aero 0.278 after.

Cal ride.jpg (69.75 KiB) Viewed 12057 times

Then, when I look at my ibike the Ibike shows aero = 0.342. If I extract the numbers from the next ride I find aero 0.342 and WS 0.877. 0.342 match the number I find in ibike after the cal-ride, but not the "check calibration".

After.jpg (35.59 KiB) Viewed 12062 times

Which Wind Scaling factor should I use?

Two files attatched in zip (zip because of 3 files limit in this forum)

[NorBike]

I see this also affects the coastdown process.
Did a new Cal Ride today, with coastdowns (because of stem adjustment and autumn clothes collection)

The iBike calculate Wind Scaling = 0.912
The Isaac calculate Wind Scaling = 0.745

The 0.745 Wind Scaling is used in the "process calibration ride" window in Isaac, and NOT the 0.912 Wind Scaling the iBike calculate (!?).

After cal-ride and coastdowns:
__________Aero______WS______Cda
Isaac_____0.355____0.745_____0.477
Ibike_____0.333____0.912_____0.365

Cda = 0.477 hmmm.....I am 178cm, 73kg's and front area around 0.33m2.

No comments from Velocomp ?....

[Velocomp]

There may be a bug in Isaac. We are looking into this.

[NorBike]

There may be a bug in Isaac. We are looking into this.

Any news?
.

[GWPOS]

I was/am having the same issue, even with coast downs. I was getting a CDA of . 550+ for all of my coast downs. Was told I could not do them where I was doing them at. I was on a 1-1.5% incline which is where I have always done coastdowns before on my Gen3. Any more flatter I would have been going downhill which IBike says not to do also.

As far as wind scaling goes, I could never get a consistant number. It did not matter if I was doing cal rides or out and backs. Wind scaling always varried between .700-.950. Was told to stop doing so many cal rides and just ride??????

That being said I use the Newton for training not general excersise so I need to rely on the numbers I see, but now I always wander if what I am seeing is even correct/accurate. This really became the case after borrowing a Powertap and comparing the ride files.

[racerfern]

If you can do a calride and a 2 mile out/back with the PT (assuming it is properly zeroed) we can get a profile within minutes that will give you confidence.

Even without the PT you can still do a cal ride and a two mile out/back, no coast downs are needed. Just punch in your weight, height, etc into the FAST START process and do the cal ride.

Upload the ride and we'll figure it out. If you prefer, you can email me at fernando.j.maldonado at gmail.com

[NorBike]

There may be a bug in Isaac. We are looking into this.

Any news?
.

Tried the OS2 and Isaac 1.05 update.
Still Wind Scaling difference between Newton and Isaac.
If using the Newton wind scaling, everything gets totally wrong in Isaac....tailwind shows as headwind.

Is this a bug in Isaac, or in Newton??...
Which factor does Velocomp recommend?...the Newton Cal ride factor, or the Isaac factor????

[still-chasing]

I still have unresolved situation regarding "Analyze route". The before and after power numbers are way off and if I click on the "Show tilt plot" that gives me another power numbers. Don't know which is true.

I'm attaching a ride file I did today. Maybe the tech guys can take a look at this and see what's wrong. I did a short out and back (marked lap) in the middle of the ride to check calibration. I still can't get my numbers to be consistent.

Also regarding another situation, how many seconds delay is showing in the display. I stomp on the pedal or go over a little roller and noticing a little lag on the display before the power goes up. Even after I crest a hill and ease the tension on the pedal, it's still showing high numbers. I know the little bars at the bottom is the actual power but when you're doing all out interval, it's hard to go by those little bars.

[racerfern]

I did a check calibration on the out/back section and I get a slight wind scaling difference to 1.009. Other than that I think it all looks good.

AFA the slight delay, there is a lot less than there used to be, not instantaneous but getting close.

[bjrmd]

I am enclosing 2 rides, same loop, wind steady each way. The corrections needed to match with the powertap are conflicting--on one a crr change is needed and on another it seems cda is way off. I am not getting the consistancy I did with the old gen 3, which once the wind cal was set was much more consistent. On days that there is little wind the number are much better however. Hope this helps

[Velocomp]

We found the bug causing this problem.

A new FW release will be coming out soon; in the mean time, you should use the Newton's numbers, not the Check Calibration numbers.

[NorBike]

Wind Scaling bug fixed in OS 2.11 !
No WS difference between Newton and Isaac, and the wind also displays correct in Isaac now

Thanks for fixing the Wind Scaling bug!

Case closed!
.