Brother Cycles Big Bro frame set, black

Ideal for bikepacking adventures and long-distance trips; perfect for the Tour Divide, the Silk Road Mountain Race and other expeditions

Works reliably with hub dynamos and USB chargers for mobiles and GPS devices.

Sizes: S, XL

Colour: Black

The Brother Cycles Big Bro frameset is a versatile adventure frame made from robust 4130 chromoly steel, ideal for bikepacking, round-the-world trips and off-road touring. It accommodates wide tyres (up to 27.5″ x 3.0″ or 29″ x 2.6″), features numerous mounting points for luggage racks and bottle cages, and comes with a sturdy steel fork with Boost thru-axles.

Specifications:

Frame & Fork

• Material: 4130 heat-treated chromoly steel, double-butted, ED-coated (corrosion-resistant)

• Fork: 4130 chromoly, tapered unicrown, 15x110 mm thru-axle (included)

• Weight: Frame (size M/18″) approx. 2.6 kg; fork approx. 1.25–1.37 kg

⚙️ Technical specifications

• Brake mount: 51 mm IS disc mount, max. rotor size 180 mm

• Dropouts: Boost 12x148 mm thru-axle (included), compatible with single-speed or derailleur

• Derailleur hanger: SRAM UDH type, fully mountable

• Seatpost: Ø 30.9 mm

• Seatpost clamp: Ø 33.1 mm (included)

• Headset: 44 mm, SHIS ZS44/28.6 top, EC44/40 bottom (not included)

• Front derailleur mount: Ø 34.9 mm, top-pull or high direct mount (adapter sold separately)

• Bottom bracket: 73 mm ISO thread

• Tyre clearance: up to 29″ x 2.6″ or 27.5″ x 3.0″

🚵 Intended use

• Perfect for bikepacking adventures, long tours and challenging trails

• Numerous mounting points for bottle cages, luggage racks and panniers

• Compatible with dropper posts (Stealth routing)

• Proven in long-distance races such as the Tour Divide (4,418 km) or the Silk Road Mountain Race (1,710 km)