Alfa
BC40
Echo
Able
Inspired by the legendary Back 40 trail system, designed by our engineers, and built entirely in our Bentonville factory – the BC40 is a modern racing machine that updates the XC playbook with the capabilities of an all-day trail sled. The bike’s 120mm suspension provides a second-to-none pedaling platform anchored by a progressive geometry that delivers precise handling and tracking with stability at speed. The XX SL Flight Attendant build makes it the ultimate racing machine, showcasing the superlative Eagle XX SL and the new Flight Attendant – SRAM’s pinnacle racing technology.
SRAM’s latest Flight Attendant actively learns how you ride and auto-adjusts your suspension on the fly to match. Every change in terrain, every change in gradient, every change in pedaling – you’ll hear your suspension adjust before you even realize it needs to. Flight Attendant maximizes your suspension’s capability to maximize your potential. Learn more about Flight Attendant.
Interested in a complete bike build? Contact us through Chat to custom-build your own BC40, and we’ll ensure you get all the right components to max-out the benefits of Flight Attendant.
Key Features
- FRAMESET WEIGHT
- 1950 grams (Lrg)
- GEOMETRY
- A slacker front headtube angle for predictable handling at speed across buff and technical terrain. A longer front-to-center measurement shifts the weight of the rider further behind the front wheel for more control to maneuver at high speeds.
- SUSPENSION
- Designed for 120mm front and rear travel, can be adjusted down to 100mm for optimal terrain performance. Faux bar system (four bar flex stay) kinematic designed for pedaling efficiency.
- COMPATIBILITY
- Cable management at the headtube allows for easy compatibility across components, including dropper posts and remote lockouts.
- BOTTLE MOUNTS
- Capable of carrying 2, 1 on the downtube and 1 on the seat tube
- TIRE CLEARANCE
- 29x2.4
Build Kit
- BOTTOM BRACKET
- SRAM Dub 73 BSA
- BRAKES
- SRAM Level Ultimate Stealth 4 Piston 180 Front / 160 Rear
- CASSETTE
- SRAM 1299 XX SL Eagle 10-52
- CHAIN
- SRAM XX T-TYPE Flat Top
- CRANKSET
- SRAM XX SL Eagle Transmission Power Meter
- FORK
- RockShox SID Ultimate Flight Attendant 120
- FRONT DERAILLEUR
- N/A
- HANDLEBAR
- ENVE M6 Carbon
- HANDLEBAR TAPE
- ESI Chunky
- REAR SHOCK
- RockShox SidLUXE Ultimate Flight Attendant
- REAR DERAILLEUR
- SRAM XX SL Eagle Transmission
- SADDLE
- Selle Italia Novus Boost Superflow
- SEATPOST
- Rock Shox Reverb AXS
- SHIFT LEVERS
- SRAM AXS Pod Ultimate
- STEM
- Industry Nine A318
- TIRES
- MAXXIS Rekon 29x2.40 WT EXO/TR Tan Wall
- WHEELSET
- Zipp 1Zero HiTop SW Carbon
Sizing Guide
| SM | MD | LG | XL | |
| Crankset | 170 | 170 | 175 | 175 |
| Stem | 40 | 50 | 50 | 50 |
Frame Geometry
| SM | MD | LG | XL | |
| A. Stack | 598 | 609 | 622 | 633 |
| B. Reach | 420 | 445 | 475 | 501 |
| C. Front Center | 710 | 739 | 775 | 806 |
| D. Seat Tube Angle | 76 | 76 | 76 | 76 |
| E. Wheel Size | 29" | 29" | 29" | 29" |
| F. Headtube Angle | 66.5 | 66.5 | 66.5 | 66.5 |
| G. Fork Rake | 44 | 44 | 44 | 44 |
| H. Head Tube Length | 95 | 105 | 120 | 135 |
| I. Bottom Bracket Drop | 40 | 40 | 40 | 40 |
| J. Wheelbase | 1145 | 1174 | 1210 | 1241 |
| K. Chainstay Length | 435 | 435 | 435 | 435 |
| L. Horizontal Top Tube | 569 | 596 | 630 | 659 |
| M. Seat Tube Length | 395 | 420 | 450 | 500 |
Features
