Trek’s ever-popular 4 Series continues as a three-bike range for 2014, with the brand including this model in its popular custom programme, Project One.
Using 400 Series OCLV (Optimum Compaction, Low Void carbon manufacturing process), the chassis is the first in the Wisconsin firm’s Madone range to use Kamm Tail technology. Derived from the motor industry, Kamm Tail aerodynamics feature on the frame and forks, sharing this design with higher-spec Madone models and, specifically, the Speed Concept time trial series machines.
Using a flattened profile on the rear of the down tube makes for a stiffer tube — it also tricks the wind into acting as though there’s a full foil. This creates a virtual tail that hugely reduces wind resistance and gives excellent crosswind performance. Better still, the Kamm Tail’s profile complies with the UCI’s 3:1 ratio, but its wind-tricking performance is equivalent to that of a 5:1 aerofoil.
It’s not just about the profiling of the tubes; the 4 Series also carries Trek’s proprietary E2 head tube that is wider side-to-side than front-to-back, with a wide 1.5in lower and 1-1/8in upper headset bearing to increase cornering performance. BB90 is also present; the 90mm-wide exclusive bottom bracket system is claimed to be one of the stiffest on the market.
Not only does the 4 Series offer most of the performance of its more costly siblings, it has some hidden talents. Vanishing mudguard mounts on the rear triangle add utilitarian potential.
The 4.5 model is all but sold out for the year, leaving just the 4.7 and 4.9 available off the peg. At £2,200, the 4.7 comes with a full Ultegra 6800 groupset, Bontrager componentry and tubeless-ready Bontrager Race TLR wheels to give a competitive package.
Should this range tickle your fancy but you want something a little special, Project One is available. We designed a 4 Series specced similarly to the 4.7 but with a customised colour. Coming out at a premium £2,789.99, this is a hefty upcharge but for a personalised, one-of-a-kind bike, it’ll appeal to those who want to stand out.