SRAM Quarq Power Meter
  • 177.5mm cranks
  • For BB30 bottom bracket type
  • 53/39t chainrings
  • 130 BCD
  • Carbon crank arms

Brand new in box

This is an older version of the Quarq power meter (bought directly from Amazon in the US), but is brand new and has never been fitted. Box only opened to take photos for this listing.

Comes complete with all the necessary components for installation (as pictured in the small plastic bags) and instructions etc.

I've fitted a new Duracell battery (CR2450) and will include a spare too (they reportedly last around 12 months and are very easy to swap).

Final two pictures show it connected up via ANT+ to my Garmin head unit (not included in sale) and to my PC, where you can also do calibration settings and diagnostics etc (requires an ANT+ USB dongle to do this, not included).

The included chainrings are 10 speed, but the power meter is also compatible with 11 speed rings.

RRP is around £1600. The cheapest I can find on-line is half price at £799 (Merlin), so grab a bargain.

Taken from manufacturers details:

Sram S975 Quarq Power Meter Crankset - GXP and BB30 BB NOT Included


SRAM’s S975 Quarq power meter is compatible with all of SRAM’s road groupsets and features an integrated carbon crank arm and proven Black RED chainrings.
 
At 779 grams (GXP, 130BCD), the S975 is a lightweight leader for wireless power devices.
It is accurate to +/- 2% and features a tool-less, user-replaceable battery and ANT+™ technology,
which gives it the flexibility to work with any ANT+™ compatible display unit.
 
The S975 is a proven performer in all environments – road, triathlon and cyclocross.
It comes in full size and compact with standard, TT/triathlon or cyclocross chainrings and is compatible with GXP,
Press Fit, BB30, Press Fit 30 and BBright bottom bracket systems.
 
Features:

  • +/- 2% accuracy
  • Tool-less, user-replaceable battery
  • ANT+™ compatible

 
The S975 is the choice of the Kenda/5-Hour Energy presented by Geargrinder professional cycling team and pro triathletes
Heather Jackson, Pete Jacobs, Luke McKenzie and world record breaker, Marino Vanhoenacker.
 

  • Arm Material:Unidirectional Carbon
  • Chainring Material:SRAM Red PG Chainrings with Anodized Coating, Alloy Chainring Bolts
  • Weight:779g (172.5mm, 130BCD, GXP)
  • Available Arm Lengths:170mm, 172.5mm, 175mm, 177.5mm
  • Available Ratios:53/39, 50/34
  • Compatibility:Compatible with SRAM Black RED and SRAM Force, Rival and Apex
  • Bottom Bracket:GXP, Press Fit GXP, BB30, Press Fit 30, Bbright
  • Chainrings:SRAM Black RED
  • Q-Factor:145mm
  • Head Unit:ANT+™ compatible head units including Garmin Edge® 800, Garmin Edge® 500 and Garmin Forerunner® 310XT (available separately)
  • Software:Training Peaks WKO+®, Training Peaks®, Golden Cheetah, Strava® (available separately)
  • Battery Type:CR2450 - over 400 hours of riding time
  • Wireless Technology:ANT+™
  • Material:Carbon crank arms, CNC machined AL spider


Quarq technology powers SRAM’s road power meters including the groundbreaking SRAM RED Quarq Power Meter.
 
How Power Meters Work:
 
Power meters calculate power by measuring the torque (pedal force) and the angular velocity (cadence). Power = Torque x Cadence.
 
When you press on the pedals, all parts of the bikes drivetrain displace (flex) slightly under the load.
Power meters are designed using Finite Element Analysis to displace in a very controlled manner in specific locations in response to applied load.
Strain gauges are used to measure the displacement and thus calculate the applied torque. Reed switches are used to calculate cadence.
 
SRAM power meters use a proprietary strain gauge arrangement and precision digital circuitry to delivery high accuracy and low power consumption for optimal battery life.
 
Inside Quarq Power Meters:
 
ANT+™: A wireless standard for bicycle electronics that ensures interoperability between sensors and bike computers from different manufacturers.

OmniCal™: Power measurement is independent from chainring selection. Switch from road to TT chainrings without impacting accuracy. No recalibration necessary.
 
Power Balance™: Displays the ratio of power generated in the right drive stroke (first half) versus the left drive stroke (second half).
Lets you work on an equal pedal stroke over 360 degrees of rotation.