PowerTap Calibration?

[Marius]

I've been getting really weird(high) watt readings as of late( be affraid) but I think it might be a glitch in my PowerTap, I want to re-calibrate it, does any one know how to do it??

[bruce]

Powertap Stomp Test http://www.midweekclub.ca/powerFAQ.htm#Q23

But I'm sure Adrian will check it out for you!

[Marius]

thx Bruce, weird, I thought one could calibrate it yourself, hmm..

[Brakkies Sport Fotos]

het jy dit op daai grondpad gebruik die naweek?

[bruce]

No, the SRM is the only unit that you can manually set the slope and offset - but generally that should not be tried at home.

[Marius]

ok ok, tell me Bruce, do you know if any one else has recorded higher Watt levels than they normally do?? I'm not saying there is somehting wrong with my powerTap but my power Levels has increased about 20Watts on AV over a 3hour ride, is that enough to be worried about?

[Trekker]

Nee, dis net genoeg om ons ander ouens te laat worry.  Jy hoef nie te worry nie M.

[bruce]

ok ok' date=' tell me Bruce, do you know if any one else has recorded higher Watt levels than they normally do?? I'm not saying there is somehting wrong with my powerTap but my power Levels has increased about 20Watts on AV over a 3hour ride, is that enough to be worried about?[/quote']

 

Check it against a previous ride on the same route with similar conditions.  Were you going faster?  How did you feel?

 

It is quite common for FTP to plateau for a while and then jump.

[Marius]

Bruce, man, it's hard to say, my HR was just in the 160's which is my Tempo pace and I should put out about 245Watts but I was putting out 270Watts easy, well my legs had a crap load of lactic asid or somehting in them when I got home, had to lay down and keep them elevated for a while. My speed was 34.1km/h over 96km, it's about 1km/h faster than usual, so I don't know, hard to say.

 

The thing is anyhting higher than 267Watts starts to fall into my L4 Levels and I was told I can't AV L4 over 3hours?

[Marius]

het jy dit op daai grondpad gebruik die naweek?

 

Nope, ek's nie stupid genoeg nie...nog nie

[bruce]

Bruce' date=' man, it's hard to say, my HR was just in the 160's which is my Tempo pace and I should put out about 245Watts but I was putting out 270Watts easy, well my legs had a crap load of lactic asid or somehting in them when I got home, had to lay down and keep them elevated for a while. My speed was 34.1km/h over 96km, it's about 1km/h faster than usual, so I don't know, hard to say.

 

The thing is anyhting higher than 267Watts starts to fall into my L4 Levels and I was told I can't AV L4 over 3hours?

[/quote']

 

Have a look at the data.  When you are viewing the graph in wko, click on the button that has "123" on it.  You will see a table with all the data samples.  Select the cadence view as well.

 

Check to see that the power samples are zero when the cadence is zero.  If not, your torque was not zero and your file will have an offset.  The FAQ that has the stomp test in it gives a procedure to correct this situation.

[Marius]

eish, that's sounds complicated Bruce, can't I email you the file and you check it for me PLEASE!!!!!!!!!!!!!!!!!!!!!!!!!!!!???????

[Marius]

OK, i FOUND THE 123 BUTTON, and were the cadance is zero the watts is also zero.

 

[bruce]

Sounds like the hub torque was fine.  Check it out over the next few rides.

[Marius]

thx Bruce, I will, my coach just wants to move my Levels up, pansie

!!! I told him to chill, lets see what happens this week

[bruce]

thx Bruce' date=' I will, my coach just wants to move my Levels up, pansie

!!! I told him to chill, lets see what happens this week

[/quote']

 

Move the levels up dude, what's the worst that can happen?  L4's just got a whole lot harder