e*thirteen Helix Core e*spec Cranks for ISIS Spindle Motor Systems - 160mm, 26mm Offset, Black

The e*thirteen Helix Core e*spec Cranks deliver an exceptional e-bike drivetrain upgrade, combining high-end structural integrity and refined aesthetics at an extreme value. Engineered to withstand the relentless torque and punishing loads of modern e-MTB riding, these cranks ensure you never have to hold back on your next gravity run. By blending a value-conscious production layout with robust construction, e*thirteen provides privateers and daily trail riders with a reliable alternative to premium-priced models without sacrificing trail confidence.

This model is engineered for standard 24mm ISIS spindle motor interfaces, offering seamless compatibility with the market's leading e-bike platforms—specifically optimizing layouts for the Bosch CX Gen 4/Gen 5, Bosch SX, TQ HPR50, Brose S Mag, DJI Avinox, Yamaha, and Specialized 2.2/3.1 motor systems. Featuring a wider 26mm offset (measured at 26.5mm offset geometry), these cranks are ideal for frames requiring maximum clearance around wide chainstays and chunky rear suspension pivots. This offset achieves a stable, highly balanced stance width with generous Q-factors depending on your motor: a precise 181mm on TQ platforms, 184mm on Bosch Gen 4 systems, and 197mm on Brose setups.

At an optimized, short 160mm length, these crank arms strike the ideal sweet spot between raw pedaling leverage and vital ground clearance on modern, low bottom-bracket frame geometries. Shorter crank lengths allow riders to maintain a fast, fluid pedaling cadence through rocky, root-strewn climbs, significantly improving technical climbing capability while minimizing the risk of high-speed pedal strikes. For ease of maintenance, the arms feature an integrated alloy self-extracting crank bolt system that makes routine home workshop servicing and installation quick, simple, and efficient.

Weighing 497g, these stealthy black crank arms are forged from high-strength AL 6066-T6 aluminum to ensure maximum durability against heavy rock strikes and accidental casing. e*thirteen packs this economic upgrade with premium attention to detail, including durable steel pedal washers to protect the spindle threads from high-load deformation and custom-molded composite crank boots that act as a resilient shield against trail debris. Fully engineered for aggressive trail duty, the Helix Core e*spec cranks are backed by e*thirteen's dependable 5-year manufacturer warranty.

Key Features

• Forged AL 6066-T6 Aluminum Construction: Delivers high-end durability, structural stiffness, and dependable trail strength at an accessible price point


• Optimized Short 160mm Length: Increases vital ground clearance on low-BB frame designs to eliminate pedal strikes while maintaining natural leverage and pedaling fluidics


• Generous 26mm Wide Offset Profile: Provides ample clearance for wide chainstays and suspension pivots, yielding a stable and comfortable trail stance


• Standard 24mm ISIS Compatibility: Designed for flawless integration with Bosch CX, Bosch SX, TQ HPR50, Brose S Mag, DJI Avinox, Yamaha, and Specialized systems


• Integrated Alloy Self-Extractor: Heavy-duty self-extracting bolt configuration makes installation and routine drivetrain maintenance efficient and tool-free


• High-End Hardware Inclusions: Comes equipped with durable steel pedal washers and high-impact molded protective crank boots for maximum longevity

Specifications

• Model: e*thirteen Helix Core e*spec Cranks


• Crank Arm Length: 160mm


• Spindle Interface Type: 24mm ISIS Spindle


• Crank Offset: 26mm (26.5mm architecture)


• Realized Q-Factors: TQ: 181mm | Bosch G4: 184mm | Brose: 197mm


• Motor System Compatibility: Bosch CX Gen4/5, Bosch SX, TQ HPR50, Brose S Mag, DJI Avinox, Yamaha, Specialized (2.2/3.1)


• Material: Forged AL 6066-T6 Aluminum


• Pedal Thread Interface: Includes Steel Pedal Washers


• Extraction Mechanism: Integrated Alloy Self-Extractor System


• Protective Hardware: Molded Composite Crank Boots Included


• Weight: 497g


• Color: Black


• Warranty: 5 Years

A durable, value-optimized alloy e-bike crank arm upgrade combining a rock-clearing 160mm profile with a generous 26mm offset, built for trail riders who demand high-end e-MTB strength, pivot clearance, and reliability without the premium price tag.