Help with low reading

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christonge
Posts: 5
Joined: Fri Apr 20, 2018 2:26 am

Help with low reading

Post by christonge » Mon Apr 23, 2018 6:17 am

Hi,

First of all hi to everyone here on the forum and secondly thanks to Velocomp for developing the Powerpod.

This is my first powermeter and I am really keen to get started and add a new impetus to my training and fitness level. I have carried out the out and back calibration ride and done a few rides with the pod and it seems consistent on all rides. I do however see that it seems to be reading between 70 or 80 watts below. I have carried out several comparisons with training partners on flat roads and it always comes out the same. In fact I was lucky enough to have a friend with a SRM that weighs and measures the same as me, ride with me this weekend, so I have now done a side by side ride and it still seems to be the same. About 80 watts lower. This is fine of course as the consistance means I´ve already done and FTP test and have been using it for intervals around the "sweet spot". BUT would you mind checking my calibration file and ride files to see if there´s anything I can tweak to get a more "accurate" reading? I would really appreciate it!!!

Look forward to hearing from you!

Chris
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iBike_04_22_2018_0951_87_km.ibr
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iBike_04_21_2018_1011_114_km.ibr
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iBike_04_15_2018_0912_5_km_CalRide.ibr
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Velocomp
Velocomp CEO
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Re: Help with low reading

Post by Velocomp » Mon Apr 23, 2018 6:35 am

What kind of bike are you riding? What kind of mount are you using?

Please post images of how your PP is attached to your bike, front and side view.
John Hamann

Velocomp
Velocomp CEO
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Joined: Fri Jan 11, 2008 9:43 am

Re: Help with low reading

Post by Velocomp » Mon Apr 23, 2018 6:45 am

One other thing: you're thinking that your PP reads about 80W low.

I took a look at your ride files and I don't see how that can be the case

1) In your 87KM ride file you have a 23 minute section where your speed is pretty constant and you are riding on the flats

2) In that section you are traveling at 21 mph and your power is 193W

3) your PP is properly calibrated

It would simply be incorrect for PP to report 270W for riding at 21 mph on the flats.
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John Hamann

christonge
Posts: 5
Joined: Fri Apr 20, 2018 2:26 am

Re: Help with low reading

Post by christonge » Mon Apr 23, 2018 8:44 am

Velocomp wrote:
Mon Apr 23, 2018 6:35 am
What kind of bike are you riding? What kind of mount are you using?

Please post images of how your PP is attached to your bike, front and side view.
Hi John,

Thanks for the quick reply.

Bike is a track bike and the PP is on the handlebar mount... see pictures.

Thanks
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christonge
Posts: 5
Joined: Fri Apr 20, 2018 2:26 am

Re: Help with low reading

Post by christonge » Mon Apr 23, 2018 8:47 am

Velocomp wrote:
Mon Apr 23, 2018 6:45 am
One other thing: you're thinking that your PP reads about 80W low.

I took a look at your ride files and I don't see how that can be the case

1) In your 87KM ride file you have a 23 minute section where your speed is pretty constant and you are riding on the flats

2) In that section you are traveling at 21 mph and your power is 193W

3) your PP is properly calibrated

It would simply be incorrect for PP to report 270W for riding at 21 mph on the flats.
Here are some like for like sections with my friend... on Saturday's 115km ride.
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WhatsApp Image 2018-04-21 at 14.26.01.jpeg
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christonge
Posts: 5
Joined: Fri Apr 20, 2018 2:26 am

Re: Help with low reading

Post by christonge » Mon Apr 23, 2018 9:19 am

This is roughly the same section on Saturday out and back

Average 35.8kph Power 190w

My estimate it should be more like 240w here right?

Thanks
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Velocomp
Velocomp CEO
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Re: Help with low reading

Post by Velocomp » Mon Apr 23, 2018 10:41 am

The issue *might* be that your PP is mounted too far from level.

The word "PowerPod" should be approximately level. In your images it is mounted pretty high in the air; it looks to be pointed up about 20 degrees, way too high.

Re-attach your mount so that PP is closer to parallel, recalibrate, then send a new ride file.
John Hamann

christonge
Posts: 5
Joined: Fri Apr 20, 2018 2:26 am

Re: Help with low reading

Post by christonge » Mon Apr 23, 2018 10:57 am

OK... will do!!! Many thanks ;-))

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