Shimano CUES ECO MTB / Urban 2x9 Drivetrain Upgrade Groupset

Shimano’s CUES ECO 2x9 Upgrade Groupset is a complete drivetrain refresh designed for modern MTB and urban bikes that need reliable shifting, wide gearing and long‑lasting components. Built around the U4000 series, this kit delivers smooth, consistent performance whether you’re climbing, commuting or trail riding, and is ideal for upgrading older 8/9‑speed bikes such as the Carrera Kraken. With multiple chainset and front‑mech options available, you can match the setup precisely to your frame, ensuring a clean fit, improved efficiency and a noticeable boost in ride quality.

• Rear derailleur: Shimano CUES RD‑U4000 2x9‑speed
• Shift levers: Shimano CUES 2x9‑speed Rapidfire Plus
• Cassette: Shimano CUES 9‑speed wide‑range cassette
• Chain: Shimano 9‑speed chain, CUES compatible
• Bottom bracket (not included):
  • BB‑MT500 – MTB, external cups, 24 mm spindle
  • BB‑MT501 – Same fit, upgraded sealing
  • SM‑BB52 – Deore‑level external BB
  • SM‑BB500 – CUES‑branded equivalent
  • SM‑BB70 – SLX‑level, fully compatible
  • SM‑BB93 – XT/XTR‑level, premium bearings
• Front derailleur (front mech) options:
  • FDU4000D – Direct mount, side‑swing, double
  • FDU4000E6 – E‑type / BB‑mount, side‑swing, double
  • FDU4000B6 – Band‑on 34.9 mm (with shims for 31.8 / 28.6), side‑swing, double
• Chainset options:
  • FCU40002BC62 – 170 mm, 36/22T, Boost
  • FCU40002C06 – 170 mm, 40/26T
  • FCU40002C62 – 170 mm, 36/22T
  • FCU40002E06 – 175 mm, 40/26T
• Brake compatibility: Works with existing hydraulic or mechanical disc brakes (brakes not included)