Cannondale's new Scalpel is unfeasibly light, without resorting to scary weight weenie tactics

With 45 World Cup podiums under its belt, Cannondale's XC race FS bike, the Scalpel, has been redesigned. It's not just a facelift - the bike's new from the bottom bracket up. A team of eight designers were tasked with the challenge of designing the lightest full-suspension MTB for the company's World Cup race team. No mean feat, given that the team riders were pretty happy with the existing Scalpel and essentially said, "If you can make something with more travel that's lighter and stiffer, that'd be great." Whether they asked for the moon on a stick too isn't recorded. But after 24 months of development, the Scalpel Carbon 100 is the result.

So what's new? The flexible carbon chainstays remain, but with the flattened section extended to deliver more flex and hence greater travel. With more displacement at the rear axle, something had to articulate between the dropout and the rocker linkage, so Cannondale has added carbon fibre seatstays to the mix which give a little. The top-flight model in the range uses a carbon-canned DT Swiss shock to trim a few more grams.

An aluminium rocker drives the shock, with the pivots for the linkage welded to an aluminium seat tube. Using technology developed for its road bikes, Cannondale has equipped the carbon Scalpel with a composite carbon fibre/aluminium main triangle. The head tube and most of the down and top tubes are carbon fibre, with aluminium tubes moulded in and welded to the alu seat tube. The shock mount is bonded to the carbon section of the top tube. Cannondale's testing persuaded them that they could deliver a lighter main triangle with the carbon/alu construction than by using carbon alone. The front triangle is claimed to be 15% stiffer than the outgoing Scalpel. As well as the carbon bikes, there'll be a range of all-alu Scalpel 100s with just a 1-200g weight penalty.

The frame then, is light, but it's in Cannondale's integrated approach that really helps the company deliver a super-light full bike package. New Hollowgram SL Carbon cranks come in at 645g including bottom bracket and three chainrings. The Lefty SL Carbon fork includes a one-piece aluminium steerer and stem and weighs in at 1.225kg (2.7lb). Throw in a selection of lightweight (but non-scary, apart from a frankly painful looking all-carbon saddle) components and the finished product comes to the start line at a mind-boggling 8.25kg (18.2lb). Cannondale reckons that that makes it the lightest bike in the World Cup field, hardtails included.

It's certainly an impressive achievement. And this top-line model isn't a racer-only special - this will be a production bike (if you have the cash). More accessible models will be available in the five-bike (three carbon, two aluminium) range.

Seat tube is aluminium and co-moulded to carbon top and down tubes

Low weight is assisted with DT Swiss's carbon shock

No pivots: instead, the chainstays flex throughout their length

Latest Hollowgram SL is lighter and stiffer