The most fundamental change relative to the multisport-oriented Plasma 2 is the revised geometry – which is now better suited for time trials with a significantly lower front end – though aerodynamics have also supposedly been improved as well with the help of former Formula 1 aerodynamicist Simon Smart of UK firm Velo Science.
As suggested in the teaser video Scott released a few weeks ago, the new Plasma 3 features an integrated stem that is positioned inline – and virtually seamlessly – with a dead-level and far lower-profile top tube.
Unlike that teaser video, though, there is no external steerer tube or fairing positioned out front a la Felt or Giant. Instead, Scott have basically carried over the nominally hourglass-shaped conventional head tube profile currently used on the Plasma 2, presumably to help ensure the bike passes muster with the recently more stringent UCI.
Further back, the Plasma 3 abandons the previous version's integrated seatmast in favor of a more conventional telescoping aero post while the seat cluster is also decidedly more pronounced than before. Scott have also moved the rear brake down towards the bottom bracket shell – just above the chain stays – thus leaving a smoother and more aerodynamic junction for the tops of the seat stays.
Down below are rear-facing carbon dropouts and radically shaped kinked chain stays similar to those on the Plasma 2 – though they're now taller presumably for improved frame stiffness – and have also added a lighter and wider carbon fiber bottom bracket shell designed around Shimano's press-fit cups.
In addition, the down tube retains its deep profile but is now repositioned slightly further away from the front wheel, thus also losing the Plasma 2's shallow wheel cutout as a result. Frame weight is around 1.4kg (3.09lb) for the current prototype though Scott expect that figure to drop closer to 1.2kg once the final design and testing work is completed.
Scott designed the Plasma 3 with the team's specific component sponsors in mind, such as Shimano's Di2 electronic group with supplemental shift buttons up on the ends of the extensions and fully internal cable routing – including wires that run through the stem and into the frame. Save for very short sections of housing or wire that exit right at their matching components, there are no visible control lines whatsoever up front and the system will still work with mechanical drivetrains according to Scott's Hermann Pacal. Shimano also provide the custom PRO carbon fiber integrated bar setup with two width options and adjustable extensions.
Ultimately, Scott plan to offer the Plasma 3 in three sizes but only mediums are available right now so just two of the Columbia-High Road riders (likely Michael Rogers and Mark Renshaw according to the team) will be on them for now with the rest coming in time for the Tour de France.
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