PowerTap P1 pedals inaccurate wattage

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

I have had my pedals for a year and they have read pretty darn close to past hubs that I have had in perceived effort to watts, so there’s that.

You’d better know your exact cda/crr/weight and be 100% correct with regards to the length and the pitch of the climb.

I have had my pedals for a year and they have read pretty darn close to past hubs that I have had in perceived effort to watts, so there’s that.

Mine as well.

You trust a guess over the pedals? I would compare them to some other measurement, rather than an estimate. Mine match my Kirt Kinetic nearly perfectly. DCR’s uses them as a baseline for multiple PM comparisons. Maybe you got a defective set. Or, maybe the guess is wrong.

Yep, I’m with the others. If you want to compare, use two PMs, not one and an online analytics tool.

RIDDEN mine a lot on a kickr. Pretty darn accurate.

match my tacx neo perfectly. I can put out much higher sustained watts on a hill outdoors than on a trainer.

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

This is not an acceptable way to test the accuracy of your pedals.

Same for me
.

I do like the pedal based meters. I just want them to be accurate cause I don’t want to think I’m stronger than I am if they are reading high. I watched these videos online and it just got me thinking about it and thought it was interesting. Especially when in the one the guy says when the P1 Pedals got over 280 they started reading 30 plus more watts than the others they tested. When i calculated all my intervals the watts were 20 to 30 more as well. Just some food for thought https://www.youtube.com/watch?v=sqb-WhzCAgw
https://www.youtube.com/watch?v=Eik97sjOpuM
start watching the video above around 4 min.

Me too. Checked mine against the LeMond Wattbox (which TBH I didn’t have much faith in accuracy-wise, but thought was good enough for a comparison for each session) and the P1’s were pretty much the same - only difference is that they read power slightly “earlier” as they’re on the pedals rather than down the other end of the drive train if that makes sense? I guess I could play with the smoothing/reading timing or something if I could be bothered.

Or perhaps they are both of similar inaccuracy…?

Have you contacted Power Tap to help trouble shoot this before you posted here? That’s a pretty considerable discrepancy and I’m sure, based on mine and others experience, their tech support would assist you.

It’s a bit disingenuous to post publicly against a product based on your experience which requires what appears to be rather critical data to be inputted into a website, before contacting tech support.

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

Oh dear.

Trust the pedals. The website makes assumptions. You think the rolling resistance is right? It likely isn’t, and do you think you have a grasp on what it should be?

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

i asked a magic 8-ball whether mine were accurate or not, it said “ask again later”, i’m going back to the bike shop and demanding a refund

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

Oh dear.

I’m fairly certain it’s a troll thread, OP probably doesn’t even own P1s.

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

i asked a magic 8-ball whether mine were accurate or not, it said “ask again later”, i’m going back to the bike shop and demanding a refund

To be fair, the Magic 8-ball has a 1 in 20 chance of creating a reproducible and accurate result. Which, is substantially more accurate than the method used above…

Just tested the Power tap P1 pedals using hill repeats and plugging in my data through this http://www.wolfgang-menn.de/ website for predicted power. My pedals are 25 to 30 watts more than the math calculation. Maybe that’s why Lionel’s power numbers are so crazy. Stupid pedals.

This is a joke right?