The Four Stroke will take you to your breaking point and leave you wanting more. Whether you are shooting for a PR on your favorite ride, or the top step of the podium, the Four Stroke will take you there. With 100mm of BMC APS rear travel and a system weight of under 2000 grams, including the rear shock; it is among the lightest and most efficient full suspension systems in the world. BMC has included the technology that has made all of their bike recognizable by design. What they refer to as "Tuned Compliance Concept" and "Integrated Skeleton Concept," translate to unsurpassed drivetrain and suspension efficiency, and ride comfort. The Four Stroke also employs a post-mount rear brake to keep things simple and save a bit of weight.
Strengths: The rear suspension on this bike is amazing. It soaks up rocks and roots and allows you to stay seated on some really difficult terrrain. I rode it in the trail setting most of the way and it just soaks up the bumps. The little suspension movement is negligible and will not rob you of energy.
The bike is really light for a full suspension bike and the frame is really stiff. I Weigh 97kg and am 1.9m tall and nowhere could I detect any flex when hammering it.
The short chainstay in the back does make for a nice playfull bike and I can imagine slapping a 120mm fork on this will transform it into a decent trailbike.
The wheels were also nice and light and seemed to just roll.
Brakes were also good on the steep stuff, but as I did not descend for an extended time I cannot comment on the usual Avid fade
Drivetrain was XX1 and performed flawless.
2014 Fox float CTD is a big improvement on the 2013 model, especially on the climb mode.
Weaknesses: The frame seemed a tad small for me but some cockpit adjustments might sort that out. It was a test bike and came with a 70mm stem. Maybe a 100mm would be better for me, but the frames only go up to a size large.
The short chainstays did make for some rear wheel movement on the steeper stuff. I guess you cannot have the best of both. The bike did not have a drop down seatpost, so keeping enough weight on the back wheel was difficult when it got steep. However nothing to complain about, you just have to learn to ride the bike
I did detect a knocking noise when going over rocks and roots while pedaling. I am not sure if this is the clutch in the rear mech complaining a bit.
I did miss a gear or two at the upper and lower spectrum of the range with the XX1.
I am picking at stuff here, but I am giving my honest opinion. Not many weaknesses on this bike
I took the bike for a 3 hour demo ride in Grenchen Switzerland, home of BMC. If I could afford this bike I would definitely buy it for marathon racing or even light trail riding. For me the 2x10 would be the ideal drivetrain for this bike. For me the best thing about this bike is the rear suspension. The fact that it is always active, a set and forget type of suspension. This was the first time riding this type of suspension(similar to Maestro and DW link) and I am seriously impressed. BMC have managed to make this bike really light and super stiff. A great buy if you can afford it.