29 Apr 2016

The company that brought us ‘over-mountain’ are back to their category creating tricks again! This time they’ve added another ‘X’ to XC with the launch of an all-new Cannondale Scalpel Si, which Cannondale say is ‘Built for XXC’. It looks bloody fantastic.

Cannondale Scalpel Si-3

In case you’re wondering, the extra X is for X-TREME, so get radical, dudes. Cannondale have designed the Scalpel to be capable beyond the bounds of a traditional XC bike (i.e. getting all XTREME), but it’s also X-TREME (ok, we’ll stop that now…) in that it’s extremely stiff, extremely light and generally on the cutting edge of this category.

Cannondale Scalpel Si-1
Fontana, AKA James Bond, was effusive about the traction afforded by the short rear end of the Scalpel Si.

Putting the XXC stuff aside, the new Scalpel doesn’t desert its racing roots but the geometry and construction have been thoroughly modernised, broadening the appeal of this already super popular cross-country machine. We took some time away from the race track at the Cairns World Cup to get a better look at the Scalpel Si. In fact, the bikes we were lucky enough to inspect were the race machines of superstar racers Manuel Fumic and Marco Fontana.

Cannondale are fortunate to have this popular and progressive pair of riders on the team; they’re well known for being incredible bike handlers, and their feedback has clearly influenced the shred-ability of the new Scalpel Si. Let’s delve into the details.

Fumic on board his Scalpel Si at the Cairns World Cup.
Fumic on board his Scalpel Si at the Cairns World Cup.
White loafers for Fontana. Regulation Italian tropical footwear.
White loafers for Fontana. Regulation Italian tropical footwear.
The 55mm offset is key to ensuring the steering is agile while still running a relatively slack 69.5 degree head angle.
The 55mm offset is key to ensuring the steering is agile while still running a relatively slack 69.5 degree head angle.
Cannondale Scalpel Si-19
Team replica colours. We weighed this frame as 2.16kg.

OutFront Geometry: More stability without sloppy handling.

The Scalpel Si gets Cannondale’s OutFront Geometry treatment. Essentially this relates to the Lefty’s large 55mm offset, which greatly reduces the the trail of the fork, allowing Cannondale to run a slacker head angle, without the usual floppy climbing performance. Paired with a shorter stem and wider bar, it gives the Scalpel more confidence-inspiring, trail-bike-ish handling, but still a nice agile, light steering feel. Cannondale aren’t the only company to use custom fork offsets to improve steering feel, but the 55mm offset is significant and should have a big impact on handling.

Cannondale Scalpel Si-10
An X12 rear axle (standard 142mm spacing) with a flex stay pivot-less rear end.

Shorter Rear End: Asymmetric Integration.

Long chain stays are so 2012. In order to get the Scalpel’s chain stays down to a snappy 435mm whilst still retaining front derailleur compatibility, Cannondale have employed their Assymetric Intergation rear end design that was initially rolled out on the F-Si hardtail. In a nutshell, the whole drivetrain is shifted outboard by 6mm, away from the tyre. To compensate, the rear wheel has zero-dish, pulling the rim back 6mm the opposite way, so your bike still rides in a straight line. The net result is that you gain more clearance for the tyre and front derailleur, while the rear wheel gets even spoke lengths on both sides, giving you a stiffer wheel.

Cannondale Scalpel Si-11
Tucking the shock up inside the top tube opens up plenty of room for two water bottles.

Flex Stay suspension with custom RockShox shock.

The Scalpel has long employed a flex stay suspension system, just like the Cannondale Habit SE we reviewed a few months ago. Using a flexing seat stay instead of a pivot point saves weight and makes the rear end laterally stiffer too, as there are fewer places for play to develop. The rear brake is mounted to the chain stay via the new flat mount standard, so the flex stay performance is unhindered by braking forces.

Check out the slick way the rear shock is partially housed within the top tube – it’s gorgeous! RockShox have worked with Cannondale to create a cleaner integration of the Full Sprint dual lockout system too. Both the fork and shock are locked at the push of a button, but the way the rear lockout line disappears straight into the frame is really very tidy, you’d never even know it was there.

Cannondale Scalpel Si-5
Clean lines.

Twin water bottles and dropper post and Di2 ready.

Cannondale have managed to create enough room up front to fit two 500ml bottles, which is a rarity with a dual suspension bike, and will be greatly appreciated by marathon racers. While none of the Scalpels come stock with a dropper, there are cabling provisions to run one. On the topic of internal routing, Cannondale have also developed a specific Shimano Di2 battery holder too, which houses the battery securely in the top tube, so you can run Di2 and a dropper without an issue. The weight of the frameset is impressive too. Just over 2.1kg including shock, rear axle, seat post clamp and the hydraulic line for the shock lock out.

Cannondale Scalpel Si-15
The brake mount is the new flat mount standard, which allows less load to be placed on the seat stays facilitating the proper functioning of the flex stay setup.

Women’s models and 27.5 wheels on smaller frames.

Cannondale have gone down the small wheels for small riders route. On size small men’s frames, you’ll find 27.5″ wheels, and both women’s models get smaller hoops too. We’re happy to see there’s a properly high-end women’s model in the range too, which is often neglected.

It’s still a few months till these bikes arrive in Australia – July or August is the ballpark. Of course, we’ll do our very best to get a ride on one before then, so keep your eye open for a write up!