Short alloy crank arms for eMTBs with a Bosch motor, CNC-machined by 5DEV from 7075 billet. 5DEV shaped the arms to cut down crank strikes when climbing through rocky, technical sections.

Highlights

  • For Bosch motors (5DEV doesn't name the motor models or generations)
  • 7075-T651 aluminium, CNC-machined from billet
  • IS spline drive
  • 440g for a 160mm set (5DEV figure)
  • 8mm hex crank bolt with a built-in 16mm self-extractor cap
  • 160 or 165mm, black or raw

Fitting

Fitting eCranks is a separate workshop service and isn't included in the price. The Tune workshop can fit them to your pedal-assist eBike and confirm your motor's crank interface first. Each arm is held by an alloy steel crank bolt (8mm hex, 40Nm) with a billet aluminium self-extractor cap (16mm hex, 2Nm), so the same 8mm hex takes the arm off again. Use a torque wrench.

About this version

This listing is 5DEV's earlier Bosch eCrank (5DEV code CB), which 5DEV listed for the Bosch motor only. 5DEV's current R-SPEC Bosch eCrank is the version it lists for Bosch, TQ and Avinox motors and the 2025 Specialized Turbo Levo 4.

5DEV eCranks by motor

5DEV makes a separate eCrank for each motor interface. Its current eCrank range includes:

  • Shimano EP8 (5DEV says its EP8 cranks also work on EP801): R-SPEC EP8 eCranks and Titanium EP8 eCranks
  • Bosch, TQ, Avinox and the 2025 Specialized Turbo Levo 4: R-SPEC Bosch/TQ/Avinox eCranks and Titanium Bosch/TQ/Avinox eCranks
  • Specialized Turbo Levo and Kenevo, first three generations (Brose motor): Specialized Brose eCranks and Titanium Specialized Brose eCranks
  • Specialized Turbo Levo SL and Kenevo SL (SL 1.2 motor): SL eCranks with the SRAM DUB spline
  • Fazua Ride 60: ETOR eCranks

Options

Every option is the same alloy arm; only the crank length and finish change.

Crank LengthColourWeight
160mmBlack, Raw440g
165mmBlack, RawNot published

Compatibility & fit

  • 5DEV lists this crank for the Bosch motor but doesn't say which Bosch motors or generations it fits (for example Performance Line CX or SX). Check your motor's crank interface with our workshop before ordering.
  • Not confirmed for TQ, Avinox, Brose or Specialized motors.
  • 5DEV doesn't publish a Q-factor for this version.
  • No chainring is listed with the arms.
5DEV backs its products with a limited five-year warranty from the date of manufacture against defects in materials or workmanship. If 5DEV confirms a defect, it replaces the product with a comparable model. If you suspect a defect, stop riding and contact us before replacing any affected parts: 5DEV's warranty is void if another maker's component is fitted in place of the 5DEV part. This is in addition to your rights under the Australian Consumer Law, so keep your proof of purchase. For warranty support, return the product to Tune Cycles and we'll manage the claim with 5DEV's Australian distributor.
  • Alloy eCranks for Bosch motors
  • 7075-T651 aluminium, CNC-machined from billet
  • IS spline drive
  • 8mm hex crank bolt (40Nm) with a 16mm self-extractor cap
  • 160 or 165mm in black or raw
Brand5DEV
ModeleCranks – Bosch (5DEV code CB, earlier version)
MotorBosch (models and generations not specified by 5DEV)
DriveIS spline
Material7075-T651 aluminium, CNC-machined from billet
Weight440g (160mm)
HardwareAlloy steel crank bolt, 8mm hex (40Nm); billet aluminium self-extractor, 16mm hex (2Nm)
Crank Length options160mm, 165mm
Colour optionsBlack, Raw
SKU DSG-5DCBosch
Brand 5DEV

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