Before the start Tour California Road Bike Action
was invited to the Columbia-Highroad team camp in Solvang, California
to take an exclusive look at George Hincapie’s Tour of California race
bike. Just moments after Hincapie completed a three-hour rain-soaked
training ride, we got a close up look at George Hincapie’s 2009 Scott Addict with Shimano’s Dura Ace Di2 electronic shifting.
For 2009, the Columbia-HighRoad team is riding carbon fiber Scott
Addicts that are constructed using Scott’s Integrated Molding Process (IMP)
and feature an integrated seatmast. Columbia is sponsored by PRO
components that supply the Vibe S7 handlebars and Vibe S7 stem. A Fi'zi:k
saddle completes the cockpit on Hincapie’s bike. Along with Shimano’s
Di2 group, Hincapie is also running a wireless SRM PowerMeter. Unlike
most professional teams, Columbia riders have their choice of wheels. For
racing, Hincapie has chosen to run Highroad labeled Zipp wheels with
Continental tubular tires. For the majority of races Hincapie will ride
a Zipp 808 rear combined with a 404 front (A 606 combination).
The aspect of Hincapie’s bike that really caught our attention was the Dura
Ace Di2 electric components. The Di2 debuted last year and is on four Team Columbia bikes. The Di2 ergonomics are slimmed down for a more comfortable grip and
feature buttons instead of shift leavers. Conventional shift cables are
replaced with wires, while the operating computer is housed in the
front derailleur. A small battery pack is mounted to the down tube just
below the water bottle cage. Attached to the stem is a small black
rectangle that houses a battery life indicator. If the battery runs low
the front shifter will shut down first, allowing Hincapie to continue
to use the rear cluster.
By using unidirectional carbon fiber brake lever
blades and eliminating all of the mechanical shifter parts, the new
Dual Control lever weight is reduced by over 155-grams over the
mechanical version. The ergonomics are slimmed down and further refined
for a comfortable grip.
PRO provides Hincapie's stem and handlebar setup. Attached to the stem is a small black
rectangle that houses a battery life indicator.
The 7.4V, Lithium Ion battery is designed to deliver reliable, long life even in the worst conditions. In conditions requiring consistent and frequent shifting, the battery is capable of 1000 kilometers of use. The battery is rechargeable and comes with a mount that easily adapts to most bikes. Lithium Ion technology is lighter, more compact and better performing than other power sources, making it a clear choice for Di2.
The front derailleur is the “brains” of the system.
The integrated ultra-compact CPU not only ensures that shifting is
perfect for both the front and rear derailleurs individually, but also
by monitoring the position of each, creates a front derailleur that
tracks the chain and requires zero manual trim without sacrificing any
shifting speed. The front derailleur logic also performs the inward
shift from the big chainring in two parts to eliminate chain drop, with
both actions measured in fractions of a second.
Like the 7900 mechanical derailleur, the 7970 has a
new carbon fiber rear pulley cage and the new design is compatible with
wider range cogsets, accommodating up to a 27 tooth cog. The
differences are the fact that the unit is now driven by a servo motor
instead of a cable and spring, so shifts are identical and precise
every time as the computer control unit analyzes each shift.
The derailleur has a built in mechanism that will allow the body to
move inward under impact to reduce the potential for damage in the case
of a crash. Cycling through the shifting a couple of times allows the
shifter and rear derailleur to automatically re-synchronize.