Garmin-Transitions time trial specialist David Millar debuted an all-new machine at this year's Giro d'Italia prologue from team sponsor Felt Bicycles. Though it wears the same DA model name, the new version's refined shape is sleeker and stiffer, and offers a more aggressive rider position than its predecessor.
Frontal area on this latest DA is claimed to be roughly half that of the 2007 version, aided in no small part by the third generation of Felt's distinctive fork, logically called the Bayonet 3. In contrast to the tapered and oversized headsets that have virtually become standard fare on road bikes, the Bayonet rotates on bearings with an inner diameter of just 19mm – about 6-10mm smaller than usual.
As before, the external steerer tube pairs with the teardrop-shaped head tube behind it to produce a more aerodynamic combination than a single structure would under current UCI rules while also making for a stiffer front end for better handling.
Felt has taken some height out of the Bayonet 3, though, and topped it with a svelte, fixed-position stem that sits nearly inline with the top tube and more easily allows for a far lower position than before – a major issue with the old version at least as far as the team was concerned, especially when they switched bar sponsors from Oval Concepts to 3T.
The fork blades have been reshaped, too, with a more gradually tapered form that omits the previous versions rearward extensions down by the dropouts.
Also adopting a slightly simplified shape is the new down tube, which skips the old DA's slight scallop around the front wheel with a more gently curving shape that still provides nearly the same amount of coverage by merely starting out lower behind the fork crown. The overall dimensions have grown, too, helping to yield a stouter front triangle that team mechanic Kris Withington says Millar praises as being "way stiffer" underfoot for notably better pedaling efficiency and steering precision.
The top tube is level as before but it, too, has grown slightly, further contributing to the frame's improved rigidity and more confident feel.
The seat tube still closely follows the rear wheel as before but is now deeper throughout its length – again, likely contributing to overall stiffness – and terminates up top in a telescoping aero-profiled carbon seatpost that includes a dedicated mount up top for a Shimano Dura-Ace Di2 battery. Down below is a newly BB30-compatible bottom bracket shell (fitted with a press-fit threaded sleeve for use with the team's Shimano cranksets).
Further back, the seat stay junction has opened up significantly, likely allowing more air to cleanly pass through and around than the old design, while the stays themselves have grown in depth and thickness. Chain stays have similarly been enlarged, but lying beneath them is one of the new DA's cleverest tricks.
Felt has moved the rear brake from atop the chain stays to below them, using a proprietary linear pull-type design that sits virtually flush with the surrounding frame surface. In addition to presumably being more aerodynamic, its brutally simple design may even shed some weight, too, and yet it still looks reasonably accessible for pad and cable tension adjustments.
Built into the new carbon rear-entry horizontal dropouts are integrated adjusters and the cable routing has been further refined to retain smoother exterior lines. According to Withington, the team is currently working with Felt to develop a fully internal setup (including through the bar and stem) for running a Di2 wiring harness.
Complete bike specifications:
Frame: Felt DA prototype, size 54cm
Fork: Felt Bayonet 3
Headset: Felt integrated
Stem: Felt Bayonet 3 integrated, 100mm
Handlebars: 3T Mistral Pro, 42cm (c-c)
Front brake: Shimano Dura-Ace BR-7800 (modified) w/ SwissStop Yellow King pads
Rear brake: Felt DA integrated
Brake levers: Shimano Dura-Ace BL-TT79
Front derailleur: Shimano Dura-Ace FD-7900-F
Rear derailleur: Shimano Dura-Ace RD-7900-SS w/ Berner carbon fiber cage and 13/15T pulleys
Shift levers: Shimano Dura-Ace SL-7900, modified for bar-end use
Cassette: Shimano Dura-Ace CS-7900, 11-23T
Chain: Shimano Dura-Ace CS-7900
Crankset: Shimano Dura-Ace FC-7900, 180mm, w/ O.symetric chainrings and custom carbon fiber cap
Bottom bracket: Shimano SM-BB80
Pedals: Shimano Dura-Ace SPD-SL carbon prototype
Front wheel: Mavic Cosmic Pro tubular
Rear wheel: Mavic Comete
Front tire: Vittoria Corsa EVO CX tubular, 23mm
Rear tire: Vittoria prototype tubular
Saddle: fi'zi:k Ares k:ium
Seat post: Felt DA carbon
Computer: Garmin Edge 500