For 2007, Yamaha have dropped their five-valve-per-cylinder design (first seen on the mid-1980s Yamaha FZ750) and gone in for the ubiquitous four-valve layout that’s favoured by all the Japanese manufacturers. The 2007 R1’s 31mm intake valves are made of titanium (25mm exhaust valves make do with steel…), the combustion chamber is more compact, and compression ratio is up to 12.7:1. Bore and stroke remain unchanged (77.0 x 53.6mm), as does the redline, at 13,750rpm. Con-rods have been strengthened for even greater durability.
As expected, the new R1 gets Yamaha’s ‘YCC-T’ fly-by-wire throttle control system, which scans changes in various parameters and adjusts fueling at up to 1,000 times a second! And that’s not all. The new bike also gets YCC-I (Yamaha Chip Controlled Intake) (YCC-I), which is how Yamaha describe the R1’s variable-length intake trumpets. This system is optimized for better torque output at lower rpm and maximum power at higher revs. 178 horsepower (at the crank) at 12,500rpm is what you get, which is just perfect!
The underseat exhaust system is now made of titanium and features dual catalyzers and an EXUP valve, which allow the 2007 R1 to conform to Euro 3 and 2008 EPA emissions norms. A slipper clutch is now standard, but last year’s LE model’s Ohlins bits are no longer available. At least for now.
Front brake discs are now 310mm (down from 320mm on the last year’s model), but Yamaha have fitted six-piston calipers on the new bike, so braking prowess should be mindblowing. Tyres are super-grippy Pirelli Diablo Corsas, which should offer near-limitless grip.
At US$ 11,600 we can only say the 2007 Yamaha R1 is a bargain. Just get One!
Update (11th September, 2007): First pics: The 2008 Yamaha R1!
Right-click and download this old Top Gear video, where a first-generation Yamaha R1 goes head to head against a Porsche Carrera...!Go here to watch this very cool video of Valentino Rossi riding the 2007 Yamaha R1 and discussing the bike's performance.
...and here's the bike in action. Amazing video!
Another video of the 2007 Yamaha R1 in action
Hi-res Yamaha R1 wallpaper here.