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
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
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.
|Name||Fourstroke FS01 XX1 (15)|
|Available Sizes||S M L|
|Rear Tyre||Continental Race-King Race Sport 29x2.2in|
|Top Tube (in)||25|
|Standover Height (in)||30.71|
|Seat Tube (in)||20.08|
|Bottom Bracket Height (in)||13.12|
|Stem||BMC MST02 70mm|
|Seatpost||BMC MSP01 Carbon|
|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|
|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|
|Headset Type||Integrated tapered|
|Rear Derailleur||SRAM XX1|
|Frame size tested||L|