E*thirteen Helix Race Crank Arm

These cranks use a standard 24mm ISIS interface, making them compatible with a wide range of motor systems including Bosch, Brose S Mag, TQ, Fazua, Yamaha, Avinox, Maxon, Sram, and Specialized SL. Always verify your motor's specific spindle interface before purchasing to ensure a proper fit.

Shorter crank arms provide increased ground clearance, which is critical for e-bikes with low bottom brackets. This helps prevent pedal strikes on technical terrain and allows you to pedal through rock gardens or uneven sections where longer cranks might clip obstacles.

The kit comes ready to install with alloy self-extractor bolts, pedal washers, and custom-molded impact boots. The self-extracting bolts make removal significantly easier during future maintenance or motor service.

Yes, they are specifically tested to rigorous E-Enduro standards. The combination of forged aluminum construction and extensive CNC machining creates a balance of high strength and low weight designed to withstand the heavy impacts and Class 5 applications typical of aggressive e-mountain biking.

The offset you choose depends on your specific motor system and frame geometry. You should consult your bike manufacturer's specifications or measure your current crank's offset to ensure the new arms maintain the correct chainline and clearance for your motor housing.