Thorn Mercury 40 Frame - 700c / 650B - Metallic Gunmetal

Introducing the Thorn Mercury 40
Celebrating 40 Years of Thorn Innovation
The Mercury 40 is our all-new, high-performance touring and sportive bike – launched to mark Thorn’s 40th anniversary. It replaces the Club Tour Mk5, Mercury Mk3 Rohloff, and the Audax drop-bar bike, combining the best features of each into one versatile, responsive machine.

Designed for Performance & Versatility
Built from Thorn 858 seamless, double-butted, heat-treated Cro-Mo steel, the Mercury 40 is engineered for a lively, comfortable ride – whether you’re chasing miles on a lightweight setup or loading up for long-haul touring.
Compatible with 700c & 650B wheels
Belt-drive ready with a frame gate
Choice of forks: Carbon disc or lightweight 853 steel
Brake options: Disc or V-brake mounts
Tyre clearance:
700c: up to 40mm (38mm with mudguards)
650B: up to 50mm (with or without mudguards)

Custom Fit Options
The Mercury 40 comes in 8 frame sizes to suit most riders:
5 sizes with long top tubes – ideal for flat bars
3 sizes with short top tubes – perfect for drop bars or a more relaxed flat bar setup
New steel fork option offers more clearance (up to 44mm with mudguards), giving you greater flexibility in how you build your Mercury.

Features at a Glance
High-quality Thorn 858 steel tubing (from our Audax Mk4)
Lightweight, sporty geometry for a faster, more responsive ride
Mounts for three bottles, a stand plate under the bottom bracket, and full touring gear
Built for Rohloff or derailleur gearing
Chain or belt drive compatible

Colour Options
Frame: Metallic Gunmetal or Metallic Orange
Forks: Black (both carbon and steel)

Who Is It For?
Whether you're upgrading from a Nomad Mk3 or looking for a bike that blends speed, comfort, and capability, the Mercury 40 is designed to handle it all — from fast club rides to multi-day touring.
One bike. Endless possibilities.

If unsure of size please contact Thorn on 01278 441505, Monday to Thursday from 8.00am to 4.00pm or [email protected]. Please note that we no longer have an open showroom.