Balancier Convexe S Green, Titanium

The Balancier ‘Convexe’ S debuted in 2020, marking the second chapter of a celebrated sports watch which took its chronometry as seriously as its liveability. The second chapter of the most sculpted and comfortable sports watch in Greubel Forsey’s collection, the Balancier S updated its aims to a thinner profile—by over 2mm—through removing complications of prior models such as the globe and tourbillon. The result was a no-nonsense, 110 gram, 30-degree inclined balance sports watch. The original run was limited to just 18 pieces at CHF 195,000, which sold immediately. This Balancier ‘Convexe’ S Green followed in 2021 as the answer to that excess demand: a small encore series of just 8 pieces worldwide, elevated by a British racing green motif—at the precise moment green dials swept high watchmaking.

The development brief was deceptively simple. Per Stephen Forsey, the starting point was to deploy the firm's in-house balance wheel at a 30-degree incline—making this the first watch in the lineup to feature the extra-large, adjustable-mass balance tilted rather than flat (in a maximally ergonomic form). The incline is not just theatre, it keeps the balance wheel out of the worst timing positions during daily wear. That geometry created real packaging problems—the inclined wheel demanded extra volume, forcing a unique layout for the 308-component movement, with the 12.6mm balance (which debuted in the Signature 1) placed at 7 o'clock. This shape and inclination defines the Convexe case which wraps around this wrist as form following function. The GMT Sport and Balancier S both debuted this curved case shape prior to the formalized naming conventions around the Convexe collection, a common point of confusion: it’s ‘Convexe’, but pre-the-Convexe-name.

The hand-wound calibre is equally clever. Power comes from two coaxial, series-coupled fast-rotating barrels turning once every 3.2 hours, one fitted with a slipping spring to prevent excess tension—hence the "Deux Barillets" inscription on the barrel’s visible top—feeding 72 hours of reserve at 21,600 vph. Above it all, a daring suspended double-arched bridge carries the inclined gear train and curved central hands. 

The details of the Balancier ‘Convexe’ S reward obsessives. The black polished escapement wheel and pallet fork directly link to the petite seconds living directly beside it. The shape of the curving power reserve hand matches the gear train bridge. Its caseback features a very contemporary recess and frosted motif, time intensive and beautiful. A simple plaque reads ‘1 of 8.’ 

The Balancier ‘Convexe’ S is a sports watch and chronometer taken to the extreme in both respects. Greubel and Stephen Forsey don't call their clients collectors, they call them custodians. This is a watch for a custodian who lives actively, doesn’t accept anything less than the ultimate, and appreciates fine skill in all respects.

This Balancier 'Convexe' S presents in exceptional overall condition. Its case bears only very light signs of careful use. The highly finished case sports little in the way of even light surface wear. The calibre is running well in specification on our timing equipment. This example comes with hits complete set.

This example is modelled on an average-sized 7-inch wrist.