2007 Yamaha YZF-R1: More And Less Of A Very Good Thing by sean bice
Monday, October 09, 2006
For fans of Yamaha's iconoclastic YZF-R1—and we know there are a lot of you—you'll be thrilled to know that the 2007 R1 is virtually everything that the 2006 YZF-R1 LE was and more. And less.
Let's start with the "less" because it's a development of historic proportions. After more than 22 years of five-valves-per-cylinder on its 750cc and 1000cc sportbikes and racebikes, Yamaha has opted for the more conventional valvetrain of just two intake valves per cylinder instead of three, along with two exhaust valves per cylinder. What that adds up is a 16-valve, four-cylinder engine instead of Yamaha's signature 20-valve engine that launched in 1985 with the Genesis concept and the FZ750N.
But fear not because Yamaha's engineers applied the age-old axiom of "less is more" with the 16-valve engine in the 2007 YZF-R1. The four-valve head design features titanium intake valves for improved low-, mid-, and top-end power. The compression ratio of the new engine is 12.7:1—which is an increase over last year's R1 and R1 LE compression ratio of 12.4:1. New connecting rods were designed with improved strength to handle the increase in power from the all-new motor.
More power. As in, a five-horsepower top-end increase (178hp)--and that's without even factoring in the ram-air effect.
But, that's only part of the "more" that's offered in the 2007 YZF-R1. The bike features an all-new fuel injection system that is complemented by a revolutionary intake system. YCC-I stands for "Yamaha Chip Controlled-Intake" and that's the new buzzword for the R1's variable intake system. The intake tracts or "trumpets" are computer-controlled to switch between 65mm and 140mm in length to optimize power output at all RPM's. This all-new, patented invention promises to do for four-stroke engines what Yamaha's YPVS power-valve system did for two-strokes back in the 80s. Varying the length of the intake runners in a four-stroke is somewhat akin to varying the port height in a two-stroke--power throughout the entire rev range instead of just on top.
Complementing YCC-I in the 2007 R1 is YCC-T, a similar-sounding acronym that stands for "Yamaha Chip-Controlled-Throttle". Like the throttle design used in last year's YZF-R6, YCC-T is a "fly-by-wire" accelerator system that provides precise throttle and engine management by reading changes in the parameters every 1,000th of a second. The result is seamless power delivery.
YCC-I and YCC-T combine with Yamaha's tried-and-true other alphabet-soup acronym "EXUP", the exhaust system valve technology that is now being copied by some of the other Japanese manufacturers. Together, these three systems provide quick starting, clean delivery, crisp throttle response, and improved exhaust emissions.
Other notable engine-related features on the 2007 YZF-R1 include a curved, twin-fan radiator for improved cooling; a back-torque-limiting slipper clutch for smoother downshifts; and a dual-catalyzer, titanium exhaust system with twin pipes exiting under the tailpiece in signature R1 fashion.
The all-new R1 sports an all-new frame that has been engineered with an ideal balance of rigidity and flex, as well as an all-new swingarm with 30% increased torsional rigidity and slightly decreased lateral rigidity. The pivot position on the new swingarm has been raised 3mm, and there is extra room for race tires than either last year's R1 or R1 LE offered.
Up front, a new 43mm fork design features larger-diameter pistons, aluminum rods, and reduced tube wall thickness. Increased axle bracket rigidity matches the increased rigidity of the rest of the new R1's chassis.
Out back, a revised rear shock offers progressive damping of 8% to 14%, along with a dual damping-speed compression adjuster. The progressive character of the shock increases from soft in the initial stage of compression to a stronger cushioning force deeper into the stroke, improving traction out of the corners.
The Rest Of The 2007 Yamaha Sportbikes And Sport-Touring Models
For 2007, the Supersport Championship-winning YZF-R6 will carry on with only minor refinements. Graphics and colors have been freshened and, like the 2007 YZF-R1, the bike will be offered in Team Yamaha Blue, Charcoal Silver/Matte Black, and Candy Red/Matte Black.
The FZ6, the second of four 600cc models offered in Yamaha's 2007 lineup (the '07 YZF-R6S and YZF600R were already introduced earlier this year), has received a number of new changes for this year—changes that transform the FZ6 into more of a "mini-FZ1". Last year, the FZ1 and FZ6 were quite different bikes, but this year, the FZ6 has adopted a lot of its big brother's attributes, such as more aggressive styling with a new fairing design and headlight shape, improved handling from a new front fork design, improved braking performance from FZ1-like mono-block front calipers, and new meters similar to those found on the FZ1. FZ6 colors for 2007 will include Team Yamaha Blue and Candy Red.
The FZ1, all-new last year, will carry on this year with graphics and color changes, namely Raven Black and Cobalt Blue. Also continuing into 2007 and receiving a new color option for 2007 are the FJR1300 and FJR1300E. These two bikes will be available in Cerulean Silver and new Black Cherry.
The 2007 YZF-R1 will come equipped with Pirelli Diablo Corsa tires-a feature that was only offered on the R1 LE this past model year. Bringing those Pirellis down from speed are all-new six-piston front calipers and smaller-diameter (310mm) front rotors, along with a single-piston, pin-slide brake caliper at the rear. The new front caliper design enables the rotor to be further out on the diameter of the disc, which reduces the inertial moment at the axle for lighter handling while under braking.
Styling-wise, Yamaha's designers chose not to mess too much with a very good thing. The iconic R1 silhouette has been preserved and freshened with some influences from the YZF-R6 that focus on aerodynamics and air management. The layered fairing helps create a vacuum that draws hot air away from the engine compartment.
An all-new multi-function meter offers a combination of analog and digital gauges, with a large, analog tachometer taking center stage like on previous R1 models.
The 2007 R1 will be offered in three color schemes: Team Yamaha Blue, Charcoal Silver/Matte Black, and Candy Red/Matte Black.
Price and date of availability have yet to be announced but, with the expected official announcement of Yamaha's return to Superbike racing in the U.S., they're going to be anxious to get the bikes into customers' hands, and at a price and in quantities that are not quite as exclusive as last year's R1 LE.
And, best of all, Daytona will be here before we know it.
