2019 Specialized Power Cranks Shimano 105 Left Upgrade In Black

Product Description

And the power cranks 105 upgrade kit is no exception. With the lightweight power sensor on a Shimano 105 crankarm its the perfect way to enter the power meter game. The development of power cranks began with the human performance team looking at riders in realistic scenarios on the bike. Historically power meters have been validated by two different methodsone is by measuring the produced torque by applying a static linear load to a crankarm or chainring while the second uses a power generating motor to pedal the bike. Well cycling is neither static nor linear & humans apply power much differently than a machine. It was found that neither of these methods answer the "real-world" accuracy question. To get the best test for accuracy in all types of riding scenarios Specialized built their own cycling treadmill, the winmill, to measure power output to a known truth. This new benchmark lets us evaluate accuracy under all riding conditions, seated versus standing, various power & cadence levels different weights & a myriad of gear. This data acquisition process is our gold-standard for testing power meters & through testing & external validation from the locomotion lab in boulder colorado power cranks have been proven to have the highest accuracy in real world scenarios (+/- 1.5%). The power cranks are also easy to live with with class-leading temperature compensation firmware & waterproof enclosures. Calibration is only required during seasonal-type fluctuations in temperature & the included wrench makes battery swaps a breeze.