Brother's robust 29er/27.5+ adventure frame for all types of use – designed to take you off-road and beyond. Whether you're riding with a lightweight bikepacking setup, packing front and rear panniers for a fully loaded world trip, or simply stripping down to the essentials on forest trails – the Big Bro is ready for anything.
The frame is now constructed from extra-tough, heat-treated, double-butted 4130 chromoly tubing and comes with a 100 mm travel fork. Both are finished with a corrosion-resistant ED coating. The Big Bro features Boost dimensions that accommodate large 27.5 x 3″ tires, or 29 x 2.6″ tires if you prefer a 29er setup. It offers hidden seatpost routing, multiple rack and bag mounts, a seat tube bottle mount, and triple mounts on and under the down tube for additional bottles and storage. The Big Bro fork also features triple mounts for additional bottle cages or an Anything Cage.
The rear triangle features S-shaped chainstays with replaceable aluminum thru-axle dropouts for geared or single-speed setups. These have been redesigned for 2025 and now feature a rail system for added strength and reliability.
Features:
- Tubing: - 4130 heat-treated chromoly steel - Double-butted main triangle, ED coated
- Brake compatibility: 51 mm IS disc brake mount, max. 180 mm rotor size
- Dropouts: Boost 12 x 148 mm thru-axle (included)
- Derailleur hanger: SRAM UDH, Full Mount Compatible
- Seatpost Diameter: 30.9 mm
- Seat Clamp Diameter: 33.1 mm (included)
- Headset: 44 mm, SHIS ZS44/28.6 top, EC44/40 bottom (not included)
- Front Derailleur Clamp Diameter: 34.9 mm Top Pull or High Direct Mount (adapter sold separately)
- Bottom Bracket Shell: 73 mm bottom bracket, ISO thread
- Maximum Tire Clearance: 29" x 2.6", 27.5" x 3.0" (Note: Not all drivetrains allow this maximum tire clearance)
- Fork: 4130 chromoly tapered fork with unicrown, ED coated. 15 x 110 mm Boost thru-axle (included)
- Full-length cable routing for rear derailleurs and brakes
- 3 bottle cage mounts for all sizes
- Chainring spacing: 48-36-26 teeth triple, 44-30 teeth double, 38 teeth single
- Weight: Frame (mid-size, 18 inches) 2.60 kg, fork (300 mm stem) 1.37 kg
- Tested according to ISO 4210 MTB standard
Product safety information
Manufacturer information:
Brother Cycles Ltd,
Brogdale Farm, Brogdale Rd
Faversham, Vereinigtes Königreich, ME13 8XZ
info@brothercycles.com
https://www.brothercycles.com
Responsible person:
BLB Netherlands - SAGE LIVE
De Kooy 7a
Wanssum, Niederlande, 5861EH
https://blbbigmama.co.uk
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Medium (18)
|
|
|
| Sitzrohr (Mitte-Mitte) / Seat Tube (C-T) |
406 |
457 |
508 |
559 |
| Oberrohrlänge / Top tube (effective) |
575 |
595 |
620 |
645 |
| Steurohrlänge / Head Tube Length |
95 |
100 |
110 |
125 |
| Sitzrohrwinkel (°) / Seat Angle |
73 |
73 |
73 |
73 |
| BB Drop |
60 |
60 |
60 |
60 |
| Steurohrwinkel (°) / Head Angle |
69,5 |
70 |
70,5 |
70,5 |
| min. Kettenstrebenlänge / min. Chainstay Length |
445 |
445 |
445 |
445 |
| Gabellänge / Fork Length |
483 |
483 |
483 |
483 |
| Gabelvorbiegung / Fork Rake |
46 |
46 |
46 |
46 |
| Stack |
598 |
605 |
616 |
630 |
| Reach |
392 |
410 |
432 |
452 |
| Überstandshöhe / Standoverheight |
782 |
810 |
840 |
871 |
| Radstand / Wheelbase |
1083 |
1098 |
1118 |
1144 |
| Alle Angaben in mm sofern nicht anders angegeben / All measurements in mm unless otherwise stated Irrtümer vorbehalten / Errors excepted |