Stefan’s stainless Sub-6 project

Stefan’s stainless Sub-6 project

I previously built this frame for Stefan, and was glad when he contacted me for another project. This time he had the goal of a very lightweight build, with the project titled ‘Sub-6’ as the aim was to have a steel framed bike under 6kg.

We opted for a stainless steel build, as Reynolds 953 is currently just about the lightest tubeset available (this alloy is very strong, which allows it to be drawn to less wall thickness – the butted tubes can be down to 0.3mm!). Stefan’s geometry requires a fairly tall headtube, so a carbon insert was added here – the extra stiffness this introduces allows the steel to be machined thinner, and overall makes the headtube lighter without compromising durability. And looks nice!

Laser engraving was used to add logos to the tubing prior to brazing the frame together, with Stefan providing his own ‘Sub-6’ logo design. The frame has a brushed finish over the raw tubes and silver fillets.

Stefan did a great job with assembling a lightweight but fully functional set of components to very clearly beat his target with the build coming in at 5.44kg (11.9lbs). Many thanks to Stefan for the photos of the complete bike, you can find his blog at: Vive le velo!


  1. Another great build for Stefan! Such an amazing display of the power of steel!

  2. Kinetic art at it’s best!

  3. Where is the rear brake?

    • Under the chainstay – direct mount.

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