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Calibration - Numbers Off???

Posted: Thu Jun 07, 2018 9:10 pm
by mwinland
I received a replacement PP last week. Finally got a chance to use it today. I am not sure I handled the setup correctly. I connected it to Isaac and sent my original profile to it. I did not do a calibration. Do I have to calibrate it if I do the profile?

One issue I had with previous PP, and this one as well, is the power numbers for the first few minutes are very high. This happens on every ride.

I also noticed on this ride (attached) the wind speed numbers seemed extremely high. I was riding in wind but I'm not sure I was riding in that much wind. Dumb question but is the wind speed based on calculation involving me riding against it at a certain MPH or is it the speed as if I was stationary? Seems high if based on stationary. Not sure that makes sense!

Anyway, do I need to recalibrate the unit? I tried this with the previous unit and I continued to have the high power numbers for the start of every ride. I'm not a fanatic but I would like to have accurate power numbers when I am riding and when I am looking at my average and normalized.

Thanks for the input!

Re: Calibration - Numbers Off???

Posted: Thu Jun 07, 2018 9:24 pm
by Velocomp
1) During the first 8 minutes of your ride your unit is recalibrating itself. If you keep PP in exactly the same position between rides this problem will be minimized

2) Your ride file shows strong tail winds on the out portion and head winds on the return. Is this correct?

Re: Calibration - Numbers Off???

Posted: Thu Jun 07, 2018 10:01 pm
by mwinland
I did have a side/tail wind out and side/head wind coming back. I just didn't think they were as strong as was noted on the device. Not sure I would be able to ride in the wind numbers it noted. I see quite a bit in the 25+ MPH range. Seems excessive to me.

Re: Calibration - Numbers Off???

Posted: Thu Jun 07, 2018 10:03 pm
by mwinland
Just to confirm, I don't need to go through the calibration process if I send my profile to new device? If I ride on Saturday should it show correct power numbers right away or should I expect the 8 minute recalibration again?

Re: Calibration - Numbers Off???

Posted: Fri Jun 08, 2018 8:30 am
by Velocomp
mwinland wrote: Thu Jun 07, 2018 10:01 pm I did have a side/tail wind out and side/head wind coming back. I just didn't think they were as strong as was noted on the device. Not sure I would be able to ride in the wind numbers it noted. I see quite a bit in the 25+ MPH range. Seems excessive to me.
I think you are OK. You had an 8 mph headwind on the return leg.

This was an out and back ride and your wind speed is symmetric.

Re: Calibration - Numbers Off???

Posted: Fri Jun 08, 2018 8:32 am
by Velocomp
mwinland wrote: Thu Jun 07, 2018 10:03 pm Just to confirm, I don't need to go through the calibration process if I send my profile to new device? If I ride on Saturday should it show correct power numbers right away or should I expect the 8 minute recalibration again?
If you don't remove your PP from your bike there should be no issue. If you DO remove it, reattach it, using the instructions, to minimize problems with the first 8 minutes.

Re: Calibration - Numbers Off???

Posted: Fri Jun 08, 2018 8:46 am
by mwinland
John,
Apparently I don't know how to read the data in Isaac because in the app the headwind and tailwind are showing much higher numbers than 8mph. I am just randomly selecting points and looking at the data at bottom of screen(attached). How did you come up with 8mph? The data in he left side (attached) shows tail 26mph and head 24mph. I'm confused at what I'm reading.

By the way, very impressed with your responsiveness on this board. I hope you get some free time! Thanks!

Mark

Re: Calibration - Numbers Off???

Posted: Fri Jun 08, 2018 12:50 pm
by Velocomp
You're using the "basic" display icons. I prefer the advanced stats display; to view it, place your mouse over the icons, then right click and select advanced stats.

In the advanced stats window you'll see average bike speed and average wind speed. The difference between the two is about 8 mph.

Re: Calibration - Numbers Off??? <Me too>

Posted: Mon Jun 11, 2018 8:24 am
by kevlar_heart
Greetings...bought the PP about a month ago and I've still not had a ride reporting power numbers in a realistic range/ Like the OP, I have about a 2 mile portion at the beginning of the ride that has me at some ridiculously high wattage....I've spoken to someone at VeloComp about that but still don't see how to avoid wasting the initial 10 minutes waiting to PP to recalibrate.

I'm also having issues with extremely LOW output readings. Going up a 7% grade the other day, PP had ne at 75 W output....not likely.

All of this PP data is pushed through a CatEye Strada Smart (which may be the problem) into Strava. I'm trying to avoid another USD 250.00 purchase on top of the USD 399.00 already spent on the PP

1) Do I need to recalibrate the PP...yet again
2) How do I avoid the initial ride recalibrate, or do I just live with it
3) Is there any better documentation on PP and Isaac? I consider myself fairly adept at analytic software (image processing), and I am at a loss to parse what the graphs are showing me in Isaac as it relates to whether the PP is working properly

My goal is to understand how my profile affects PP on my road bike, so I can also create a profile for my gravel bike and move the PP from bike to bike as needed.

Attached are the IBR files for the last calibration ride and a couple of recent rides lasting over an hour.

Many thanks for the help!

Re: Calibration - Numbers Off???

Posted: Mon Jun 11, 2018 8:26 am
by kevlar_heart
Other attachments didn't work...let's try again
iBike_06_07_2018_1520_29_Miles_HiDef.ibr
(959.58 KiB) Downloaded 223 times
iBike_05_29_2018_1559_18_Miles_HiDef.ibr
(586.13 KiB) Downloaded 206 times
iBike_06_09_2018_1333_19_Miles_HiDef.ibr
(591.28 KiB) Downloaded 218 times

Re: Calibration - Numbers Off???

Posted: Mon Jun 11, 2018 11:06 am
by Velocomp
Your speed sensor is misbehaving. You can see dropouts on the bike speed graph. What kind of sensor do you have? Where is it mounted?

In the 6/7 ride I looked at, you are pushing 338 watts up a 7% grade at the end of the ride; this is reasonable.

Still, until you get the speed sensor problem fixed, your data will be flaky.

By the way: I LOVE your handle! I purchased one of the first Kevlar canoes made, back in the mid 70s. It is a fantastic material, but I hope you don't have any implants using it :-)

Re: Calibration - Numbers Off???

Posted: Mon Jun 11, 2018 12:41 pm
by kevlar_heart
Velocomp wrote: Mon Jun 11, 2018 11:06 am Your speed sensor is misbehaving. You can see dropouts on the bike speed graph. What kind of sensor do you have? Where is it mounted?

In the 6/7 ride I looked at, you are pushing 338 watts up a 7% grade at the end of the ride; this is reasonable.

Still, until you get the speed sensor problem fixed, your data will be flaky.

By the way: I LOVE your handle! I purchased one of the first Kevlar canoes made, back in the mid 70s. It is a fantastic material, but I hope you don't have any implants using it :-)
Hi: Wahoo Speed sensor. It's mounted on the front wheel hub. No problems with that sensor in Strava or on the bike computer. Would a re-pairing of speed/cadence sensors be in order?The handle is from my Army days...


************
I'm going to reset the speed sensor. Re-pair the sensor to PP. Turn off PP (12 button presses to reset right), go for a ride and see if there is any difference.

The bike computer shouldn't have any effect on PP performance except as a conduit to Strava. The PP data in Isaac shows anomalies....those are independent of any computer in the mix....So....let me do my homework and get back to you. If I should send something to Support, let me know

Re: Calibration - Numbers Off???

Posted: Mon Jun 11, 2018 1:30 pm
by Velocomp
I would replace the Wahoo sensor with one from Garmin. The Wahoo sensor has dropout problems--something that is widely known.

You won't see speed dropouts on Strava or your bike computer. They last for a very short period of time. This is not enough to cause overall problems, but it is a big issue for PowerPod, which needs accurate and uninterrupted speed data to compute power accurately.

Re: Calibration - Numbers Off???

Posted: Mon Jun 11, 2018 1:38 pm
by kevlar_heart
Velocomp wrote: Mon Jun 11, 2018 1:30 pm I would replace the Wahoo sensor with one from Garmin. The Wahoo sensor has dropout problems--something that is widely known.

You won't see speed dropouts on Strava or your bike computer. They last for a very short period of time. This is not enough to cause overall problems, but it is a big issue for PowerPod, which needs accurate and uninterrupted speed data to compute power accurately.
Well gee, I'd really like to avoid throwing away sensors. Nothing in your literature suggested that Wahoo was unreliable when I was purchasing the PP -- just that ANT+/BLE compliance was necessary. I replaced the Cateye BT sensors because they didn't play nice with PP. I have Wahoo Speed/cadence sensors on both bikes. I really don't want to keep throwing money at the problem of getting the PP to do its thing.

Is replacing the speed sensor my only option?

Re: Calibration - Numbers Off???

Posted: Mon Jun 11, 2018 2:30 pm
by Velocomp
Please email me at jhamann@velocomp.com

Re: Calibration - Numbers Off???

Posted: Wed Jun 13, 2018 6:55 am
by kevlar_heart
Velocomp wrote: Mon Jun 11, 2018 2:30 pm Please email me at jhamann@velocomp.com
Sent ride data and message

Re: Calibration - Numbers Off???

Posted: Wed Jun 13, 2018 1:26 pm
by Velocomp
Look for a response from Tom. If you don't see one quickly check your spam folder!

Re: Calibration - Numbers Off???

Posted: Wed Jun 13, 2018 6:39 pm
by kevlar_heart
Velocomp wrote: Wed Jun 13, 2018 1:26 pm Look for a response from Tom. If you don't see one quickly check your spam folder!
Nada in either...I'm not real good at patience LOL :lol:

Re: Calibration - Numbers Off???

Posted: Wed Jun 13, 2018 9:19 pm
by Velocomp
kevlar_heart wrote: Wed Jun 13, 2018 6:39 pm
Velocomp wrote: Wed Jun 13, 2018 1:26 pm Look for a response from Tom. If you don't see one quickly check your spam folder!
Nada in either...I'm not real good at patience LOL :lol:
email me jhamann@velocomp.com

Re: Calibration - Numbers Off???

Posted: Thu Jun 14, 2018 2:22 am
by kevlar_heart
Velocomp wrote: Wed Jun 13, 2018 9:19 pm
kevlar_heart wrote: Wed Jun 13, 2018 6:39 pm
Velocomp wrote: Wed Jun 13, 2018 1:26 pm Look for a response from Tom. If you don't see one quickly check your spam folder!
Nada in either...I'm not real good at patience LOL :lol:
email me jhamann@velocomp.com
John....I sent it to you again....same address as profile address on BB

Re: Calibration - Numbers Off???

Posted: Thu Jun 14, 2018 9:14 am
by Velocomp
kevlar_heart wrote: Thu Jun 14, 2018 2:22 am
Velocomp wrote: Wed Jun 13, 2018 9:19 pm
kevlar_heart wrote: Wed Jun 13, 2018 6:39 pm

Nada in either...I'm not real good at patience LOL :lol:
email me jhamann@velocomp.com
John....I sent it to you again....same address as profile address on BB
Response sent.

Re: Calibration - Numbers Off???

Posted: Sat Jun 16, 2018 9:12 am
by FrankH
kevlar_heart wrote: Mon Jun 11, 2018 1:38 pm
Velocomp wrote: Mon Jun 11, 2018 1:30 pm I would replace the Wahoo sensor with one from Garmin. The Wahoo sensor has dropout problems--something that is widely known.

You won't see speed dropouts on Strava or your bike computer. They last for a very short period of time. This is not enough to cause overall problems, but it is a big issue for PowerPod, which needs accurate and uninterrupted speed data to compute power accurately.
Well gee, I'd really like to avoid throwing away sensors. Nothing in your literature suggested that Wahoo was unreliable when I was purchasing the PP -- just that ANT+/BLE compliance was necessary. I replaced the Cateye BT sensors because they didn't play nice with PP. I have Wahoo Speed/cadence sensors on both bikes. I really don't want to keep throwing money at the problem of getting the PP to do its thing.

Is replacing the speed sensor my only option?
John
I was a little concerned by your response to kevlar_heart since I'm also using a Wahoo speed sensor. I've just checked the documentation that came with my PowerPod and the relevant page is also available in your support section: https://velocomp.com/wp-content/uploads ... 102516.pdf
7. Most ANT+ speed or speed/cadence sensors will work with PowerPod BLE, for example (this list is not complete):
a. Garmin “magnet-less” speed and cadence sensors
b. Wahoo Fitness BLE/ANT+ speed and cadence sensors (“dual band” operation)
c. iBike speed/cadence sensor
My Wahoo speed sensor seems to be performing correctly but it's still a worry if you say they are problematic.

Re: Calibration - Numbers Off???

Posted: Sat Jun 16, 2018 2:32 pm
by Velocomp
Unfortunately this is a somewhat complicated subject.

The link you provide is about the BLE version of PowerPod, and the Wahoo sensor reference in that document refers specifically to Wahoo's BLE implementation of speed. We have not seen any issue with Wahoo BLE speed signals.

The Wahoo sensor is both BLE AND ANT+; where we see issues on the ANT+ side.

The speed data below is from a Wahoo ANT+ sensor. You'll notice speed notches throughout the section. We don't know why this happens; what we do know is that Wahoo is the only sensor where we see this problem.

All of this aside, I don't mean to cause unnecessary alarm. Glitches in speed signals can make the power signal more noisy, but that doesn't mean the power data is "bad".