BMC Gran Fondo GF01

BMC have taken their ‘tuned compliance concept’ (TCC) – the process of optimising the carbon layup in each part of the chassis, adding flex and stiffness where each is needed – to new levels here.

The head tube is oversized and tapered – and taller than the race RM01 as the GF01 has BMC’s ‘endurance fit’ – the down tube is massive, and there’s a burly BB86 press-fit bottom bracket shell, complete with integrated chain catcher, and huge chainstays. 

The top tube is radically slim in comparison, and BMC’s signature low-set seatstays have a noticeable kink to the brake bridge; this ‘angle compliance’ is evident at the top of the chainstays too, and effectively lengthens both, resulting in a rear end that’s as supple as anything that we’ve tried.

The seatpost is similarly kinked, with a carbon layup that allows it to flex forward and back under your weight over broken surfaces. It works remarkably well; we even had to move our saddle up a little to take into account the flex when seated.

Up front, BMC have radically redesigned the fork. The steerer tube still tapers to its massive 1 1/2in lower diameter, and retains the broad and deep crown, but the legs slim down towards the dropout, with the final couple of inches of the forward facing ‘angle compliance’ even slimmer still. The effect is a fork that’s strong and stiff at the top but flexes at the dropouts to take the sting out of bumps and cobbles.

We could wax lyrical about the benefits of the drivetrain from Ultegra’s Di2 electronic groupset, but that’s really just the icing on a very smooth cake. Faultless gear changing and compact gearing make the moving parts the perfect companion to the GF01’s exceptional frameset.

It all adds up to a ride that’s so far beyond the currently considered benchmarks of comfort/endurance orientated road bikes that the GF01 sets a whole new standard. But there’s more to the BMC story: the whole concept is designed around running 28mm tyres.

The tyres look huge, absolutely dwarfing standard 23mm tyres. Plenty have already expressed their doubts about running such a fat tyre on a race machine, but after putting a few hundred miles into riding them we’ve been impressed. 

BMC and tyre manufacturer Continental recommend running the 28s at 80-90psi, which is much lower than we’re used to, and this lower pressure combined with Easton’s new RT wheelset with its wide 17.5mm rim makes for a ride that’s beautifully cushioned and smooth rolling.

That’s kind of what you’d expect in such a high volume tyre, but what is surprising is the cornering ability they offer: throw the GF01 downhill and the levels of grip are way beyond anything we’ve experienced before, and we mean anything. You can simply descend as quickly as your nerve will allow.

The downside is that there is a bit more weight at the rim, meaning an increase in inertia when setting off, and it’s hampering on climbs where the gradient starts to get towards double figures, but aside from on some serious Alpine climbs, where we would revert back to skinnier tyres, this is something we could live with for the rolling benefits, comfort and grip.