Rotor - Spares - INpower - Rex 2 Left Arm/Axle

£540.00 £378.00

Rotor MTB Rex 2 Left Arm+ Axle for INpower Your mtb is more than just an accessory to your lifestyle; it's your tool for training. Discover where you push hardest in... Read more...

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SKU: ROC1302019110002


Rotor MTB Rex 2 Left Arm+ Axle for INpower
Your mtb is more than just an accessory to your lifestyle; it's your tool for training. Discover where you push hardest in your pedal stroke, despite varying terrain How you transfer power off-road will vary as much from the way you ride as to where you ride. The INpower REX 2.1 single chainring 1x cranks place power meter technology inside the crank axle where is protected it from loose rocks and other shocks, crashes, and outside contaminants like mud, sand, and clay. If you know your Optimum Chainring Angle, which you can find with INpower's TORQUE 360 and OCA pedal analysis, you can dial in your oval QX1 rings to your advantage. Forged and CNC-machined in Spain from 7075 aluminum alloy, INpower REX 2.1 for MTB features unprecedented data sampling technology, which takes into account abrupt changes in terrain like jumps and drops to accurately measure your power output.


  • - Spider: 76 BCD
  • - Sizes: 170/172.5/175mm
  • - Battery specifications: AA 1.5 V
  • - Estimated battery life: 300 hours riding time
  • - Water resistance: IPX7
  • - Strain gauges: 4 gauges in the axle
  • - Wireless technology: ANT+™ 2.4 Ghz
  • - Weight without batteries: 566g
  • - Data transmitted: power, cadence, TORQUE 360, OCA, torque effectiveness (left side), pedal smoothness (left side)
  • - Head unit: ANT+™ compatible head units
  • - Analysis Software:
  • - Crank Software: ROTOR INpower User Software
  • - Q-Factor: 163 mm
  • - Chainline: 50.6 mm
  • - Material: 7075-T6 forged and CNC-machined aluminum alloy
  • - Compatibility: bottom brackets BSA, BB89, BB92, BB30, PF30, BBRight, Cannondale F-Si Ai (spider sold separately), oval and round chainrings,76BCD, 9,10 and 11 speed


While Rotor might be best known its flagship Q-rings, which helped power Carlos Sastre towards his 2008 Tour de France victory, the proudly Spanish brand can also count victories in the Giro d'Italia and Vuelta a España. Going far beyond its beginnings, Rotor has also innovated in the world of beautifully designed and exceptionally crafted cranks, power meters, round chainrings, bottom brackets and accessories - all honed in professional cycling and triathlon to give the ultimate in performance and all showcasing Rotor's extraordinary made-in-Spain quality.


Founded by real cycling enthusiasts in 2004, our passion for elite performance runs through everything we do at Saddleback. Our team of dedicated roadies, mountain bikers and triathletes practice what we preach to bring you the finest cycling products and a superior service to match. We're the official UK home of 3T, Alchemy, Castelli, Chris King, ENVE, Sidi, Silca, Stages and Troy Lee Designs.


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