bc40

SRAM XX SL Flight Attendant Bike

Current lead time 4 - 6 weeks.

$12,350

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
Have a Question?

Lightweight Frame

When traversing countless steep pitches, weight matters. The target 1950g frame weight is achieved by careful placement of the most advanced composite materials available and countless hours iterating and testing to ensure ride performance, durability and strength are all in perfect balance.

Lightweight BC40 on path

Lightweight Frame

When traversing countless steep pitches, weight matters. The target 1950g frame weight is achieved by careful placement of the most advanced composite materials available and countless hours iterating and testing to ensure ride performance, durability and strength are all in perfect balance.

Two Bottle Mounts

Hydration is critical on any long ride or race. The BC40 design allows for a full size bottle on the downtube and small bottle on the seat tube.

Two Bottle Mounts

Two Bottle Mounts

Hydration is critical on any long ride or race. The BC40 design allows for a full size bottle on the downtube and small bottle on the seat tube.

Aggressive Geometry

The needs and capabilities of a modern cross country bike have completely evolved. BC40 pushes the envelope of race worthy bikes with a 66.5 degree headtube angle and 76 degree seat tube angle to allow you to optimize your weight well behind the front wheel for descending and further forward when climbing in the saddle.

Aggressive BC40 geometry on trail

Aggressive Geometry

The needs and capabilities of a modern cross country bike have completely evolved. BC40 pushes the envelope of race worthy bikes with a 66.5 degree headtube angle and 76 degree seat tube angle to allow you to optimize your weight well behind the front wheel for descending and further forward when climbing in the saddle.

Made Here

Like all ALLIED bikes, the BC40 is carefully crafted one frame at a time in our headquarters in Bentonville, AR to ensure each bike is built to the highest standard of quality possible.

Carbon fiber and tooling in Allied factory

Made Here

Like all ALLIED bikes, the BC40 is carefully crafted one frame at a time in our headquarters in Bentonville, AR to ensure each bike is built to the highest standard of quality possible.

120mm Travel

BC40 bolsters a full 120mm of travel front and rear with kinematics carefully positioned for pedaling efficiency and easy tunability.

120mm travel rear suspension

120mm Travel

BC40 bolsters a full 120mm of travel front and rear with kinematics carefully positioned for pedaling efficiency and easy tunability.

Customer Reviews

Based on 3 reviews
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Anonymous
BC40 Exceptional

The team at Allied was great and kept me informed during the order/build process. The product far exceeded my expectations. That Harlequin purple/green is gorgeous, and component build with XX SL, and Flight Attendant makes the bike fly uphill. It is amazing how efficient this bike is, and at the same time comfortable. I would highly recommend the BC40, as well as any purchase from the amazing team at Allied.

B
Brian Herlihy
BC40 6000 mile review

I bought my BC40 as a frameset just about a year ago and have put 6000 miles on it. I built it up with Trickstuff C44 brakes, Royal Control SL Wheelset, SRAM XXL Transmission, Gemini Integrated Bar and Fox suspension and fork. I love the bike. The geometry fits me perfectly, balances my weight in a perfect triangle over seat and handlebar. Without pedals - the setup is right about 10kg. The BC40 is very efficient, yet comfortable. I did the 24hour MOAT last year and was shocked how comfortable the bike held up (3D Specialized saddle helps too). I would highly recommend the BC40.

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Anonymous
good bike

This is a fantastic bike I would recommend it is a little pricey but it has electric everything and its so pretty rides super good