The Yamaha YZF-R1, a More Technical Look
With the latest Yamaha YZF-R1 the sophisticated bodywork does more than cover up the ugly bits. The lower fairing cowl is now composed of separate inner and outer shells engineered to more precisely control airflow around the latest Yamaha YZF-R1 at high speeds. Yamaha calls this 'Active Air Management', this Active Air Management system is designed to force cool air into the radiator and more efficiently suck hot air out of the engine bay, eliminating the need for hot-air vents at the sides of the radiator and thus improving aerodynamics.Radically enlarged ram-air ducts dominate the upper fairing. New headlights are the latest two-stage projector beams, and both remain lit in high- and low-beam operation. The latest Yamaha YZF-R1 has a shorter, tighter tail section which is designed with mass centralization in mind.
Yamaha's signature electronic technology remains intact, including YCC-I chip-controlled intake runners that snap from a low end-boosting length at 9,400rpm. Ride-by-wire YCC-T throttle activation remains, powered by a 32-bit ECU that separately maps each cylinder's ignition and fuel-injection. The YCC-T technology also drives the Yamaha YZF-R1's new D-mode function that enables the rider to adjust performance characteristics according to three preset drive modes. Unlike Suzuki's similar S-DMS system, which alters power delivery via changes in ignition and injection timing, D-Mode simply alters the speed at which the YCC-T system opens the throttle plates.
In addition to the standard setting, there's also an accelerated 'A' mode for sharper throttle response and a 'B' mode that softens response.
The Yamaha YZF-R1's Deltabox aluminum frame has been completely redesigned to complement the Crossplane powerplant. A gravity-cast headstock/front engine mount connects to a gravity-cast front engine mount connects to a gravity-cast rear section with frame rails formed using Yamaha's controlled-fill die-casting process, balancing vertical, lateral and torsional rigidity to improve stability at lean.
According to Yamaha, vertical rigidity is increased by 22 percent, lateral rigidity is decreased by 37 percent and torsional rigidity is reduced by 2 percent. Controlled-fill casting technology also forms the one-piece magnesium subframe, shaving precious weight from the center of mass. The swingarm, consisting of a gravity-cast main section fitted with CF-cast spars, has likewise been retuned for 28 percent more vertical rigidity, 21 percent less lateral stiffness and 29 percent less torsional twist resistance – all to exploit the additional available traction.Geometry remains essential identical, though, with the same rake (24 degree) and trail (101.6mm). Only the wheelbase – just 5mm shorter – has changed. And a taller 55-series rear tire helps the latest Yamaha YZF-R1 turn a bit quickly.
For suspension, a new Soqi fork isolates compression and rebound-damping functions, with the left leg dedicated to the former and the right to the later. This independent arrangement simplifies suspension adjustments, improves response and stability over changing surfaces, and eliminates the dead zone where conventional forks transition from compression to rebound action. A Soqi shock offers high/low-speed compression damping and the added compression damping and the added convenience of a hydraulic spring-preload adjuster, which adjust with an Allen wrench instead of a spanner.
This new shock rides on a new bottom link-type rear suspension stroke. Featuring a more progressive leverage ratio, this linkage provides improved small-bump compliance in the beginning of its travel and firmer resistance to big inputs.
The engine, excepting Ducati's Desmosedici RR, no other production sportsbike so closely resembles its MotoGP forebear as the new Yamaha YZF-R1. Crossplane crankshaft technology comes directly from the Yamaha YZR-M1 racebike, with each crankpine located 90 degrees from the next to decrease inertia torque. Technically this is not a 'Big Bang' engine, which fires pairs of cylinders simultaneously, but rather a 'Long-Bang' design with an uneven (270-180-90-180) firing interval that offers a degree of the big-bang's traction-enhancing benefits with less vibration and top-end power loss.
The latest Yamaha YZF-R1's displacement remains at 998cc, but the bore has increased 1mm (to 78mm), and the stroke has been shortened accordingly (to 52.2mm, from 53.6mm).
Otherwise, engine geometry is essentially identical to the previous model. Fracture-split connecting rods drive forged pistons inside friction-reducing ceramic composite-plated cylinders, while titanium intake valves slash reciprocating mass. For the first time, the Yamaha YZF-R1 gets secondary, showerhead-type fuel-injectors to better fill its 45mm throttle bodies, improving throttle response and high-rpm power. The EXUP valve has been deleted from the titanium exhaust and a more efficient, three-way catalyst replaces the previous two separate catalyzers.
