October 19, 2007 Next year’s R6 might not look very different to the current model, but under the sharp-looking bodywork Yamaha’s 600cc Supersport missile has received some significant revisions aimed at improving the bike’s already scalpel-like handling and screaming power.As always, the 600cc Supersport road/track bike category will be extremely hard fought in 2008. With Triumph’s class-smashing 675 Daytona ruling the roost from out of nowhere for the last two years, the Japanese companies are throwing all their knowledge and technology at the category to wrestle back their supremacy. The customer is surely the winner in this battle - next year’s Yamaha YZF-R6 will contain more electronic goodies and tricky technology straight from the racetrack than anything that’s preceded it.
While the largely unchanged bodywork will fool many buyers into thinking the 08 model’s a mid-generation minor update, there’s actually been a complete overhaul under the bike’s skin.
Chief among the more interesting updates is the electronically controlled variable length intake system, previously only seen on the 2007 R1, and top of the range MV Agusta superbikes.
Bikes deliver bigger, smoother power at low revs with a longer set of intake trumpets, but they benefit from shorter air intakes to deliver maximum power at high revs. In most cases, a compromise is chosen. The Yamaha Chip-Controlled Intake system (or YCC-I) has a set of lightweight resin extension funnels that lengthen the intakes at low revs, but lift off when the bike hits a certain magic rev count to leave the shorter intakes exposed.
Yamaha claim the transition is quick and smooth, and virtually undetectable – a clear reference to the annoyingly jerky two-to-four valve VTEC transition that has turned so many riders off Honda’s recent VFR800s.
The 2008 R6 will retain a re-tuned version of the 07 model’s fly-by-wire chip controlled throttle system, which worked pretty much flawlessly to deliver power intelligently when required. The chip-controlled throttle and intakes work together with the injection system to strike a fine fuel-air balance across the rev range and at different throttle openings.
The screaming motor will deliver a healthy 135 horsepower through the use of the highest compression pistons Yamaha have ever used on a bike. The final compression ratio will be a sky-high 13.1:1, so owners had better remember to use the high-octane fuel to prevent pre-ignition. Higher compression will mean more engine braking – but this is unlikely to cause riders any serious issues, as the bike is fitted with a slipper clutch to limit back-torque.
The Deltabox frame has also been revised – in particular, the thickness of the main frame spars has been reduced to give the frame a little more sideways flex. This might sound odd, seeing that the last 30 years have seen frames become stiffer and stiffer in the name of pinpoint control – but when the bike is right on its ear in a corner, a little sideways flex acts as a backup suspension component to keep the tyres nicely planted when the forks and shock are working at their limits.
The sub-frame holding the seats and rear end up is now made from ultra-light magnesium, in a first for Yamaha – representing a weight saving of around half a kilo and contributing to the 52.5% front wheel bias of the bike’s weight. A redesigned swing-arm (slightly longer, to counter the squatting effect under acceleration) and lightened rear shock suspend the rear wheel. Both the forks and shock feature the same excellent high- and low-speed compression damping adjustability of the 2006/7 bike.
Brake discs are 0.5mm thicker, adding gyroscopic moment to the front wheel – an interesting move, since it also adds to the unsprung weight of the bike, but Yamaha feel that the extra mass helps deliver a more planted and trusty sensation to the rider, as well as being more efficient in heat dissipation.
The riding position has also changed subtly – if you found the last R6 a little extreme in its race focused crouch, you’ll be dismayed to hear that the bars are slightly lower and further forward – which Yamaha believe gives the rider a better connection with the feedback from the front end. In other words, more race focused and less road comfort focused than ever – but that’s what buyers seem to want from a supersport.
The Yamaha press release doesn’t mention a redline figure – which is interesting in light of the glitch surrounding the company's claim of a 17,500RPM redline on the 2006 model which turned out to be optimistic by about 9%.
And so the march of Supersport progress moves on – ever lighter, ever faster, ever sharper and usually at the expense of road usability. The low-end boost provided by the R6’s nifty YCC-I system might make it a slight exception to the rule, but it will have to stand and be judged against the barnstorming Daytona 675 triple, which has proven itself to be one of the best roadbikes ever built, and is slowly trickling into national-level supersport racing with an eye on the World Supersport contest in years to come. And that’s not to mention the brutal competition from the other Japanese manufacturers in the tightest production class of all.