7th Heaven
7th Heaven
Yamaha YZF-R7 Superbike
DON CANET
GO ON, ADMIT IT: You want this bike, you neeeed this bike. What’s the bottom line, you say, where do I sign? Hey, whoa ’er down there, Mr. Trump. Having the cash is not always enough. Particularly when demand exceeds supply and a qualified race resume is a prerequisite.
When Yamaha unveiled its liter-class YZF-R1 last year, the first question on the minds of many wasn’t how fast or how much, but rather, when would there be a 750cc Superbike version? The answer is now. The new YZF-R7 completes the R-series trilogy, returning Yamaha to the front of the 750 tech wars.
Unfortunately for the masses, current plans call for just 50 R7s to be imported to the U.S. this year-the minimum number required to meet homologation for AMA Superbike racing. Ten of these have been delegated to Yamaha’s in-house Superbike team, with the remaining bikes to be sold to qualified racers/teams that have submitted a proper resume. With the list of applicants already outnumbering the available bike count, it appears that the R7 may be out of reach for even the wealthiest spoilbike enthusiast. Wasn’t it Pink Floyd who sang. New ear. caviar, four-star daydream, think I 'll buy me a Superbike team ?
Even within the motopress community, the YZFR7 has remained an elusive entity, with only a handful of journos worldwide invited to ride the newest addition to the YZF-R family. I make the cut, plucked from the masthead to spend a day aboard racekitted R7s circulating Circuit de Jerez, located in Spain’s southernmost region. Yeah, baby!
Why not use stock streettrim R7s? Glad you asked. Although the YZF-R7 is sold in street-legal guise, its primary lot in life is to lose the lights and win on the track. As sold, the engine is detuned to adhere to Germany’s maximum power restriction. Yamaha elected to keep things cheap and simple by applying that 106bhp state of tune-that’s 14 less than the claim for stateside R6s-to all R7s currently being built. This fact only underscores the machine’s primary intent for roadrace conversion. R7s won’t remain stock for very long.
Spread out across a table in the Jerez pits was a myriad of race-kit parts for journalists to fondle. Comparing the relatively modest inventory of R7 components to the sizable race kits available for the Suzuki GSXR750 or Honda RC45, you might assume Yamaha has overlooked a few key areas. In reality, though, many of the components needed for the YZF-R7 to sit in good standing on a Superbike grid are already present in the street-based machine. Yamaha’s R-series project leader, Kunihiko Miwa, pointed out that a major design concept was to mini-
mize the amount of modification required to reach a competitive level. You needn’t look far beyond the standard R7’s 106-horse hobble to see Miwa’s team has achieved its goal.
Sharing the basic R1 layout, the R7’s 749cc engine uses a compact vertically stacked, three-axis transmission and a one-piece cylinder/crankcase. Its 72 x 46mm short-stroke dimensions and low reciprocating mass make for a snappy, rev-happy motor. Within the electroplated cylinders run
lightweight forged-aluminum pistons. Those have nickle-coated crowns and deliver an 11.4: l compression ratio. Lightweight Hsection titanium connecting
rods, developed for the R7 by Formula One component manufacturer Ken Matsuura, mate the pistons to a special lightweight, ion-nitrified crankshaft.
To enhance intake and combustion efficiency, the five-valve cylinder heads feature ultra-precise CNCmachined combustion chambers and intake ports. Additionally, full race-spec cams actuate lightweight titanium valves with aluminum valve-spring retainers, allowing the engine to rev more freely to higher speeds.
Keeping pace with current trends, Yamaha equipped the R7 with an electronic fuel-injection system featuring two injectors per cylinder. A primary injector located in conventional fashion downstream of the throttle valve delivers crisp response, while a secondary injector sprays fuel directly into the velocity stack for enhanced peak-power performance. A multi-function ECU controls ignition timing, injection timing and injection volume. A host of sensors monitors crankshaft, camshaft and throttle position along with various temperatures and pressures, enabling the powerplant to maintain optimum performance in a range of conditions.
Use of the race-kit wiring harness is the key to unlocking the R7’s full power potential. Plugging the kit harness into the standard ECU activates pre-programmed full-performance fuel and ignition maps, and enables race-mode functions built into the cockpit instrumentation. While the instrument pod appears to be identical to an RI ’s, its internal circuitry is quite different. With kit harness attached, the speedometer readout displays water temperature and the odometer functions as a lap timer manually triggered with a thumb switch on the left handlebar. What’s more, the high-beam indicator assumes the role of shift light, illuminating 300 rpm prior to maximum revs. A switch box plugs into the harness at trackside and can be used to adjust fuel and ignition settings along with selecting either a 14,000rpm ignition cutout for endurance racing or 14,300rpm rev limit for sprint use.
Other engine-related mods on the bike 1 rode at Jerez included a kit head gasket (one of five available thicknesses) used to adjust squish area and raise compression; race-spec surface-discharge sparkplugs; high-flow fuel pump and regulator; and an airbox kit that replaces the Stocker’s snorkel lid with a sealed carbon-fiber top. It draws cool air through a foam filter force-fed by a ram-air duct routed through the upper-middle of the radiator. The coolest-looking kit bit? The radiator set, a massive, double-row work of art offering extra capacity and greater surface area than the standard two-piece item.
Keeping with the minimal-mods theme, the standard exhaust header is utilized. The kit exhaust consists of just a tailpipe and a carbon elliptical silencer, your basic “works” slip-on that mounts to the stock stainless 4-2-1 header. Likewise, the stock wet clutch is retained, although it benefits from a higherpressure diaphragm-type spring to handle the engine’s increased output.
Prior to heading onto the Jerez track for the first of several 30-minute riding sessions, I climbed onto the R7’s firmly padded saddle to familiarize myself with the riding position and controls. A more compact and aggressive riding posture than the Rl, with clip-on
bars placed farther forward and lower. The footrests offer no fewer than nine placement options! Unlike its R-series siblings, the 750’s shift linkage is routed outboard of the frame to facilitate a reversed, one-up five-down, GP-style shift pattern.
Once the tire-warmer blankets had been removed from the fresh soft-compound Michelin radial slicks, I rolled out of the garage and bumpstarted the engine to life.
My anticipation reached a boil as I sat on pit lane, blipping the throttle and watching the water temp slowly rise on the digital dash display. After a couple of orientation laps to get a feel for the bike and pinpoint a few damp spots on the track from a passing storm, I was already quite comfortable with the R7. It’s a rare occurrence to gain such confidence in a thoroughbred racebike so quickly. I was immediately taken by how incredibly smooth everything was. From the feathery-light
clutch pull, to the engine’s silky sewing-machine feel, to the chassis’ nimble, neutral steering, the R7 experience was like riding in seventh heaven. Its quickaction throttle assembly-reducing grip rotation to 60 degrees-made for ultra-sharp throttle response. In the early going, the sudden power response was unnerving when leaned over full-tilt in one of Jerez’s trio of low-gear hairpins. As I logged more time on the bike I was able to smoothly apply the power as needed, finding the balance between grip at the rear and tire contact with the ground up front.
When I asked about claimed power output, no answers were forthcoming. My seat-of-the-pants impression would suggest in
the neighborhood of 145 horses at the rear wheel. Put another way: Wheelspin off a fourth-gear corner? No problem. Power wheelies? How many gears do you want to carry it? With plenty of midrange power to play with, taking Jerez’s hairpins
a gear taller was a viable option that still had the front wheel floating on exit. Keeping the tach around 10,000 rpm through any apex left a 4000-rpm topend spread in reserve for uninterrupted drives. I found running it out nearer the 14,300-rpm rev limiter-which cuts power subtly-offered an effective safety net in comers where the rear tended to break traction. When the tire lit, allowing the revs to suddenly pick up, the limiter helped bring the rear back in line smoothly.
Ripping through the closeratio gearbox on either of Jerez’s straights was a festival of sound and fury. Clutchless upshifts under full power seemed to require a more deliberate throttle roll out-to unload the gear dogs-than what I’d consider typical. The hot setup would no doubt be an electric shiftkill for full-throttle shifting. In fact, the kit harness comes pre-wired to use the sidestand switch-on a special bracket-as the trigger for just such a setup. Nice touch.
Another nice touch was the light, progressive feel at the front brake lever. Here, the standard 320mm rotors and R1-style four-pot calipers had been upgraded to race-spec Nissin six-piston billet binders acting on 320mm stainless rotors.
Nissin master cylinders are used for the brake and hydraulic clutch. The rear caliper/rotor combo offered little stopping power, typical of race setups.
Although mid-aftemoon rain showers put a stop to our fun, the future looks bright for Yamaha’s assault on the World Superbike Series. Japanese ace Noriyuki Haga put in a strong showing aboard his R7 in the series opener-a rostrum finish was in the bag had he not slid off while charging for the front. With plenty of rides yet to come, Haga will undoubtedly display the YZF-R7’s full potential to the world.
At least for the time being, your best bet for logging seat time on a YZF-R7 may be to land a ride on a top-level Superbike squad. Who knows, with the right sponsor backing, you may even be able to buy your way in. To paraphrase Pink Floyd again: Money, so they say, is the root of all racing today. But if you ask for a ride it 's no surprise that they ’re giving none away.
