With the proliferation of standards and chainring configurations, Rotor decided the smartest course of action was to create a crank component system so that one crank could work with multiple bikes and chainring combinations. That crank is the R-Raptor. Turns out, they could also make the system lighter and stiffer than a traditional crank and spider setup.

The R-Raptor refers to the two crankarms of the set. To finish the set, you’ll need an axle (the Hawk/Rotor axle, in both standard and Boost), chainrings (1x only with options for both round and Q-ring), and potentially crankarm bumpers. All of which R&A has.

The arms are, like most of Rotor’s products, extensively CNC-machined aluminum. The alloy used is 6082

The arms come in three lengths: 165, 170, and 175mmWeight for the 175mm arms with a standard axle and.30-tooth chainring is 715g.

These arms attach to a 30mm diameter spindle that can work with nearly any bottom bracket standard that works with 30mm spindles, including English-threaded bottom brackets of any width. The one bottom bracket standard it won’t work with is Trek’s BB95The arms come with crankarm fixing bolts installed.

The Rotor R-Raptor Crankarms are what you see and need when building a Rotor crankset system.