BMC Fourstroke FS01 XX1 review

A trail happy yet super accurate and efficient experience

Our rating 
4.5 out of 5 star rating 4.5
GBP £4,800.00 RRP | AUD $9,449.00 | USD $7,999.00

Our review

Swiss maximum speed efficiency with infectious surefooted confidence and control that makes technical trails a ton of fun
Skip to view product specifications

The Fourstroke impressed us a couple of years ago, but World Cup tweaking has made it even more capable and controlled without dulling its rock solid, powerplay character.


Frame and equipment: max power, max precision design

The massive down tube dominates the chassis and locks down bar to bottom bracket stiffness so you can wrestle maximum watts through the pedals. The big symmetrical chainstays, offside triangulating strut and full carbon through axle dropouts make for an equally stiff rear subframe.

BMC has softened the low speed compression shock tune compared to the rattle and chatter of the original Fourstroke we tried. The twin linkage design still means an efficient rather than exaggerated suspension character though, even if you flick the CTD damping adjuster to fully open for maximum traction on choppy terrain.

The down tube dwarfs most other elements of the landscape:
Russell Burton

The down tube dwarfs most other elements of the landscape

Add high tension, high stiffness DT Swiss wheels and you’ve got an inspiring platform through which to exert your energies.

The RaceSport tyres add additional puncture protection, 180mm brake rotors mean decent power from ultralight SRAM XX brakes, and it’s stealth dropper post compatible.

Ride and handling: laser-guided trail boss

As much as the stiffness impresses, it’s the way the BMC bosses the trail that’s really noticeable for an off the peg race bike. While it’s certainly not a full enduro cockpit the 720mm bar width, 70mm stem and massively solid mainframe give the steering authority.

There’s no twist or deflection through the suspension or wheels either and the longest top tube and wheelbase on test gives it a surefooted, planted feel. The Continental tyre combo is definitely bred for speed rather than grip, but the Fourstroke carves corners harder and more consistently than either Cannondale’s Scalpel or Trek’s boutique-y Superfly Project One, which we took out to test alongside it.

Race-honed it may be, but the fourstroke oozes authority on the trail:
Russell Burton

Race-honed it may be, but the Fourstroke oozes authority on the trail

The chassis stiffness also keeps the suspension working efficiently to sustain speed and let the tyres track the ground. While they’re stiff in tracking and torque terms the split top tube and thinwall frame tubes developed from BMC’s road bike R&D also noticeably damp vibration and buzz on high speed trails.

The naturally progressive suspension can take surprisingly large hits and decent sized drops in it’s stride too and it’s easy to balance fork and shock response for a totally predictable ride.


Our only grumbles were the rumbling overkill chain guide stirrup on the chainstay which snapped off on the second ride anyway and the all too easily spun out 30T chainring. That’s hardly a deal breaker considering the relatively high value of this searingly fast yet seriously enjoyable Swiss superbike.

Product Specifications


Name Fourstroke FS01 XX1 (15)
Brand BMC

Available Sizes S M L
Rear Tyre Continental Race-King Race Sport 29x2.2in
Wheelbase (in) 45.32
Top Tube (in) 25
Standover Height (in) 30.71
Seat Tube (in) 20.08
Chainstays (in) 17.52
Bottom Bracket Height (in) 13.12
Weight (kg) 10.37
Stem BMC MST02 70mm
Shifters SRAM XX1
Seatpost BMC MSP01 Carbon
Seat Angle 73.5
Saddle Fizik Tundra 2
Rims DT Swiss XR1501 Spline One
Rear Wheel Weight 1980
Rear Shock Fox Float CTD Factory 100mm travel
Bottom Bracket SRAM PF GXP
Front Hub DT Swiss XR1501 Spline One
Brakes SRAM X.0 180/180mm
Cassette SRAM X01 10-42T
Chain SRAM XX1
Cranks SRAM XX1 30T
Fork Fox 32 Float CTD Adj FIT Factory Kashima 100mm
Frame Material APS carbon fibre
Front Tyre Continental X-King Race Sport 29x2.2in
Rear Hub DT Swiss XR1501 Spline One
Front Wheel Weight 1680
Grips/Tape BMC lock on
Handlebar BMC MFB01 720mm
Head Angle 70
Headset Type Integrated tapered
Rear Derailleur SRAM XX1
Frame size tested L