POWER METERS: Crank, Hub or Pedal-based?

[Minion]

hi,

 

Was jus reading this thread and I'm not inspired by the amount of drift in the quarq. Is this a common experience among those of you that use a quarq and is it an annoyance

 

http://www.quarq.com/forum/thread/286/

Mine drifted from about -120 to about -380 over the first week of riding. It's now been stable at around -380 for around 8 months. It looks like they need a bit of bedding in over the first couple of rides.

 

Edit: During a ride, the drift is within 20pts or so from start to finish. Most of that seems to occur in the first 15min of riding (possibly acclimatisation).

Edited May 3, 2012 by Minion

['Dale]

Mine drifted from about -120 to about -380 over the first week of riding. It's now been stable at around -380 for around 8 months. It looks like they need a bit of bedding in over the first couple of rides.

 

Edit: During ride, the drift is within 20pts or so from start to finish. Most of that seems to occur in the first 15min of riding (possibly acclimatisation).

 

Much better review.

Thanx, minion.

[Spinnekop]

That drifting.......Torquing the chain rings correctly is of UTMOST importance.

I had a huge drift -380......did the torque at 10nm and it shifted to -100

 

It will differ from day to day and is influenced a lot by temperature.

 

With the quarq you just pedal backward 4 times and it zeros again. Something I do every now and again in a ride, especially if I started in the cold early hours of the day.....

['Dale]

That drifting.......Torquing the chain rings correctly is of UTMOST importance.

I had a huge drift -380......did the torque at 10nm and it shifted to -100

 

It will differ from day to day and is influenced a lot by temperature.

 

With the quarq you just pedal backward 4 times and it zeros again. Something I do every now and again in a ride, especially if I started in the cold early hours of the day.....

 

Very interesting...

[Minion]

Very interesting...

Every single strain gauge-based power meter will be affected by temperature because of the way the technology works. Provided you zero beforehand and the PM temperature doesn't vary significantly during the ride, it will not have a significant effect on the power readings.

[DangerDave]

a nice function of the Power Tap is that it will auto zero, every time you free wheel for longer than 30sec and there is no power recorded it will auto zero.

 

 

I think this is the only PM to do so.

 

 

A manual check of the calibration can also be done and anything between the values of 500-530 is considered acceptable. New values are 512.

 

 

A manual zero can also be done as what is done with SRM

[Zac.A]

a nice function of the Power Tap is that it will auto zero, every time you free wheel for longer than 30sec and there is no power recorded it will auto zero.

 

 

I think this is the only PM to do so.

 

 

A manual check of the calibration can also be done and anything between the values of 500-530 is considered acceptable. New values are 512.

 

 

A manual zero can also be done as what is done with SRM

 

Power2Max auto zero's after 3 seconds with no recorded power/cadence.

[Zac.A]

I may have a powertap elite+ built into a DT Swiss RR465 up for sale soon, will let you guys know.

[Zac.A]

Look Keo Polar Power pedal is out.

 

When I looked there were 4 in stock, probably going fast...

 

http://www.wiggle.co.uk/look-keo-power-pedal/?utm_source=facebook&utm_medium=wiggle-social-media&utm_campaign=lookpower

[LOOK695]

For those interested, DC Rainmaker has written a review on the SRAM RED 2012 Quarq power meter

[capeofstorms]

Based on the above article from DCRainmaker it appears unless you have the newer SRAM groupset, from a money perspective the SRAM power crank does not make sense, unless you want to fork out for a set of STI's and front deraileur as well

Edited May 17, 2012 by capeofstorms

[Bike Mob]

It's not all bad news: http://velonews.competitor.com/2012/03/news/it-works-we-test-sram-red-backwards-compatibility_209270

 

There is still a full list of compatibility and most drawbacks are effected in the 39/11, which you should not be using anyway

['Dale]

I may have a powertap elite+ built into a DT Swiss RR465 up for sale soon, will let you guys know.

 

@ Zac.A,

 

Is this the new one you just got.

 

You were gonna send a review here.

 

I am still floating around in the market.

['Dale]

Got a quote to buy Quarg in USA for 1800 and a bit dollahs...

[Zac.A]

@ Zac.A,

 

Is this the new one you just got.

 

You were gonna send a review here.

 

I am still floating around in the market.

 

Nah, thats the wheel based one.

my dad has taken it over for the moment will let you know first if it's for sale.

 

also saw the new red groupset with a quarq pm the other day!

looked so good, go for it if you can :thumbup:

['Dale]

Nah, thats the wheel based one.

my dad has taken it over for the moment will let you know first if it's for sale.

 

also saw the new red groupset with a quarq pm the other day!

looked so good, go for it if you can :thumbup:

 

Thanx, Zac, for that feedback.

 

I smaak the SRM as a first choice. Quargie 2nd choice.

But after care is a hassle with the annual servicing by sending it to Europe.

 

No rush here.

Still weighing up options.