Race Face

Aeffect R ETOR E-MTB Crank Arms

What Our Gearhead® Experts Are Saying:

"I like these cranks for riders who want a tough, affordable alloy option for Bosch-powered E-MTBs. The ETOR interface fits cleanly, the arms are stiff under load, and they hold up well to repeated impacts. They’re a solid upgrade or replacement for aggressive E-bike use."

The Race Face Aeffect R E-MTB Crankarms are purpose-built for the unique demands of modern E-bike riding, where high torque, repeated impacts, and sustained power output place extra stress on drivetrain components. Designed around the ETOR motor interface, these crankarms integrate seamlessly with Bosch Gen 4 drive systems, delivering reliable power transfer and consistent performance on steep climbs and technical descents.

Constructed from 7050-series aluminum, the Aeffect R E-MTB crankarms offer an ideal balance of stiffness and durability while keeping weight competitive for an alloy E-bike crank. The forged construction resists flex under heavy motor-assisted loads, maintaining a precise pedal feel even during hard accelerations. Shorter arm length options improve ground clearance and reduce pedal strikes, making them especially well suited for technical trail and enduro-style E-MTB riding.

Recommended for trail, enduro, and all-mountain E-bike builds using Bosch Gen 4 motors, the Aeffect R E-MTB Crankarms are a dependable choice for riders who demand strength, compatibility, and confident performance from one of the most critical contact points on their E-bike.