In what was a highly anticipated move, Cannondale finally unveiled a 29in-wheeled version of their ultralight Scalpel carbon fiber cross-country bike at this year’s Sea Otter Classic in Monterey, California. We weren’t able to ride it but it looks set to be one highly sought-after machine.
Though it shares the same name as the 26in-wheeled version, the Scalpel 29 strikes us as more of an ultralight short-travel trail bike than a full-out racer. The 1.9kg (4.19lb) claimed frame weight – which includes a Fox Racing Shox RP23 rear shock – is about 340g heavier than the 26in version and the 100mm of rear wheel movement should certainly be more versatile than the 26in bike’s more minimal 80mm, especially when the bigger wheels are factored in.
Cannondale forego the standard Scalpel’s pseudo-pivotless rear end in favor of a bona fide single-pivot suspension layout, with a main pivot anchored in-line with the seat tube and just above the bottom bracket shell. There’s still a short upper link to help keep the rear end in check and control the shock rate, though, and the Scalpel 29 also uses strategically flattened seatstays with built-in vertical flex to account for geometry changes as the rear triangle moves through the travel.
The seatstays flex slightly as the Scalpel 29’s rear end moves through its 100mm of travel
Stiffness seems to play a bigger role on the big-wheeled version, too, with several design pages borrowed from the company’s longer-legged Jekyll. Both the main pivot and the swing link’s lower pivot use a 15mm through-shaft design to quell torsional flex, the rear brake uses Cannondale’s proprietary adapter system (that supposedly frees up design constraints around the rear end), and there’s even a 142x12mm through-axle rear end with hollow carbon dropouts.
Additional features include a PressFit 30 bottom bracket shell that allows for a lighter carbon fiber sleeve (Cannondale’s BB30 setup requires a machined aluminum insert), a direct-mount front derailleur that tracks the chain throughout the travel range, an external upper cup that drops the top tube for slightly more standover clearance, and a clever pivoting housing stop on the chainstay bridge that automatically aligns the cable path for Shimano or SRAM front derailleurs.
The swingarm-mounted front derailleur tracks the chain throughout the travel and also allows for more complex seat tube shaping
In terms of frame geometry, Cannondale say the new Scalpel 29 uses a 70-degree head tube angle and 73.5-degree seat tube angle, a 33.5mm bottom bracket drop, and relatively long 452mm chainstays. Combined with what we expect to be smoother and more plush-feeling suspension action (we’ve found the 26in Scalpel to ride rather stiff, true to form with its hardcore racing intentions), the Scalpel 29 is apt to be an ideal marathon machine.
Cannondale say the carbon Scalpel 29 will be offered in two build kits (final specs and pricing to be determined) and four frame sizes from small to extra-large. Projected delivery is around September or October. There’s no word on pricing yet.
Cannondale apply their own brake stud mounting system (previously seen on the Claymore and Jekyll) on the new Scalpel 29. Once the proper adapter is fitted, though, it’s the same as industry-standard post mounts