Rotor Bike has been in the cycling industry for over twenty years. Based in Madrid, Spain, they have been looking for a solution to better connect human legs designed for running to perfectly round pedaling circles. After a whole host of weird and wonderful systems
, they have settled on pushing oval chainrings. They also make a range of cranksets, power meters, and more recently complete road bike groupsets, all made at their own engineering plant in Spain. The R-Hawk is their take on an enduro/downhill crankset, the modular system can be pick-and-mixed from the ground up including different axle widths and weights, direct mount chainrings, arm length and silicone protectors in various colors.
A crankset including chainring and axle comes in at $345 USD or €345.
Construction R-Hawk Crankset Details
• Arm length: 165/170/175mm
• Axle: 30mm
• Q-Factor: 164 mm / 170mm boost / 179mm DH
• Chainline: 49,5mm / 52,5mm boost
• Material: 7055 aluminum, 100% CNC-machined
• Compatibility: BBRight / BB30 / PressFit30 / BSA 68mm, 73mm and 83mm
• Silcone protectors in seven colors
• Made in Spain
• Weight: 798 grams (165mm arms, protectors, 32t ring, Boost axle and BSA BB)
• Price: $345 USD / €345 (exc. BB)
Being a small brand, Rotor wanted to create a system that could adapt to ever-changing industry standards, which is why they went with a modular system that allows any Rotor axle, bottom bracket, crank arm and chainring to work together. This also means that if you manage to bend a crank arm, or change bikes and need a new bottom bracket or axle width, you should be able to buy the necessary parts individually.
The cranks start life as an extruded lump of 7055 alloy, which Rotor says has the same mechanical properties as the more common 7075 series, but with better fatigue properties. Each extrusion goes through an ultrasonic check by the supplier to discover and eliminate any defects found in the raw material. The crank arms are deeper than most and have three holes bored through their full length to save weight. This also means they could shorten the overall length of the crank arm by removing material on the terra-firma side of the pedal axle, which should be great news for those who suffer rock strikes.
The R-Hawk cranks appear to be ready to withstand anything, but for safety, there is added silicone protection to ward off shoe rub and rock strikes for today's low bottom bracket society. And, for the color-coding crowd, there are seven shades to choose from.Installation
Fitting the R-Hawk cranks was a doddle. Using the included wrench to thread in the BSA threaded bottom bracket, install the 30mm axle (Rotor say their axles are machined within a 29.99-30.0001mm tolerance) with the correct spacers, then attach both of the arms. The chainring simply slots on to the splined OCP system and the parts are laser etched to make sure you have everything the right place. Finally, the bottom bracket preload can be adjusted using the non-drive side collar and locked in place with a 2.5mm Allen key. Removing the cranks is easy, as both sides are installed with self-extracting bolts.Performance
I set the Q-Ring in the standard position and got on with it well from day one, barely noticing the need for a different pedaling technique. As I mentioned in my Starling Murmur review
, it did seem to mess with the anti-squat of the bike, but this will vary between bike and setup. For me, pedaling the oval Q-Ring is definitely more comfortable, smoother, and provided better grip and power transfer on loose terrain than a round ring. I tried to adjust the Q-Ring slightly either way but ended up back at the standard position. If you are not a fan of oval rings, Rotor makes a standard round ring to fit the OCP system with a narrow-wide design.
Underfoot, the cranks feel solid. After months of abuse and rock smashes they are still in one piece and straight. The lack of material on the outside of the pedal threads help with a few more millimeters of clearance and the silicone protectors dampen alloy vs. rock striking noises.
Looking down on the crank arms they are quite straight compared to others that have more of an 'S shape' shape to give ankle clearance, and although I didn't have any problems knocking my ankle bones the anodizing has started to wear. The drive side bottom bracket bearing has started to feel a little rough as well, but still spin freely after more than 400 kilometers of riding in winter conditions.Pinkbike's Take: