E*thirteen Helix Core e*spec Cranks

The Helix Core e*spec cranks are designed specifically for systems using an ISIS spindle interface, including Bosch CX Gen4/5 and Brose S Mag motors. Please verify your motor's spindle type before purchasing to ensure a proper fit.

While carbon fiber is lighter, forged aluminum offers superior impact resistance and durability, which is often more critical for the high-torque, gravity-focused demands of e-MTB riding. These cranks provide a robust, reliable platform that handles rock strikes and heavy loads without the fragility sometimes associated with carbon.

Installation is straightforward with a standard hex wrench, and the cranks feature self-extracting bolts, which simplifies removal significantly. You won't need a dedicated crank puller, making maintenance much easier to handle at home or on the trail.

The molded impact boots protect the ends of your crank arms from rock strikes and trail debris, which can cause structural damage or cosmetic wear over time. They are a simple, effective way to extend the lifespan of your cranks, especially if you ride in rocky or technical terrain.

This specific model comes in a 170 mm length, which is a standard, versatile choice for most e-mountain bikes. This length balances pedal clearance with leverage, providing a stable feel for a wide range of rider heights and riding styles.