(left) Just 50
examples of the R7 are
coming to the States,
10 of which go directly
to Yamaha USA's AMA
Superbike team.
(Right) Though
'designed to be street
legal with proper
switchgear and
gauges, the R7 was
designed as a race
bike.
style on the backshiit to take advantage
of the slipper clutch fitted as standard,
getting the maximum amount of engine
braking available. Don't, however, do
this too eagerly: I had the back wheel
hopping into the tight tum at the end of
the main straight at first, until I realized
the nonadjustable setting of the backtorque limiter doesn't really like you to
use more than 12 grand on the overrun.
I suppose it's a way of reminding you
that this is not a Desmo, so don't get too
enthusiastic and tangle those valves.
Your best plan is to brake hard first and
offload some engine speed before downshifting.
The R7's well-braced swingarm follows the R1 forma t of being very long
and pivoting close to the far-forward,
high-set gearbox sprocket. Combined
with the control of the multi-adjustable
Ohlins shock, this delivers the excellent
traction Yamaha claims for the design,
wi th the possibility of varying the
adjustable pivot height over a range of
8mm to maximize grip.
As the day got hotter at Jerez, the
softer rear tire started to slide around a
bit exiting turns. Going to the next-hardest compound knocked another second
off my lap times, even though the loss of
grip had been easy to control. The R7
eems very forgiving in its handling, as
well as very stable - that word again! - if
you spin the back wheel and have it
hook up again suddenly.
It didn't send the bike into a weave
when this happened, nor when I kept
making the same mistake and turned
too early into the second fast left on the
circuit, a fourth-gear tum where baclcing
off the gas to avoid running out of road
only brought a loss of momentum, not a
lack of stability. Eventually, I finally
learned that to do the turn right, you
have to run over the rough patch of
pavement in the middle of the track. But
here again, the R7 coped fine: no wobbles, no shakes, just planted.
Perhaps it's no coincidence that
Miwa-san says the design of its
..: Deltabox U chassis is largely derived
~ from Yamaha's YZR500 GP bike's
as the best-handling
Grand Prix racer both now and for the
past several years, especially in terms of
torsional rigidity, total stiffness and
weight di tribution. Being so strongly
based on that bike, it isn't surprising to
find out that the R7 frame has extra
sheeting compared to the Rl, with no
elbow cutouts as on the bigger bike, all
for lOD-percent \Dcreased stiffness over
the Rl's frame, and an incredible 240percent stiffer than the old YZF750, all
for quicker steering and more stable
handling.
.
'1 designed the Rl as a street bike,"
says Miwa, "but as some customers discovered, there is some compromise for
racing - the chassis must be stiffer, to
accept slick tires. On the R6, I always
had in mind that this must be two bikes
in one - it must be a racer, on treaded
tires, as well as street bike. But on the
R7, I always designed it as a racer. There
is some compromise for the treet, but
this is secondary to the main purpose,
which is to win races. So, though Yamaha staff give me the name of 'Mr. 0
Compromises: on the R7 I made many
compromises - but only for street use!"
Okay, great frame - but how about
the engine? Well, though the design of
the R7's motor (weighing 137.3 pounds,
compared to the Rl's 144.5) is all-new
and the details refinecl including the
adoption of an integrated engine-management system incorporating Ef1 (not
like the RC45 Honda's, which has separate fuel and ignition packages), it
retains the 72 x 46mm dimensions of the
old YZF750, as well as its 20-valve forma t, now with offset chain drive to the
twin overhead camshafts.
That's also the same bore and stroke
as the Suzuki GSX-R750, and like the
works Suzuki I rode at the end of last
season (though at that stage still in carbureted form), the Yamaha has an u1traprogressive rather than explosive power
delivery even in race-kitted form, and
doesn't rev as high as you might expect
(the works Kawasaki screams to 15
grand). The soft-action rev-limiter kicks
in at 14,300 rpm, with a blue light flashing on the dash 500 rpm below that to
warn you that it's nearly time to shift
gear.
When you do make that shift, after
overcoming the disappointment of finding no power shifter at home (though
the kit wiring loom is programmed to
accept a KLS system), you realize the
gearbox has a crisp, clean action and
well-chosen ratios 'in standard form,
though of course the cassette-type
extractable cluster allows you to vary
these at will - and more easily than on
Suzuki's less-ideal layout.
.
The 45mm throttle· bodies of the Nippondenso Ef1 each have twin injectors,
one centrally located outside the air
trumpet (the length of which can be varied according to the circuit, with a shorter race-kit option for more top-end performance), the other just after the
throttle butterfly, with a clean shot at
the three intake valves. Remapping the
ECU is done by remote access using a
switch box supplied with the race kit no EPROM chips to swap - and in the
form I rode it at Jerez, the engine was
very clean-revving and responsive, with
no compromises I could discover in the
mapping, apart from the reason for the
high, 1500-rpm idle. This is the fierce
pickup from a closed throttle after entering a tum hard on the brakes. When you
open the gas again, there's a sudden,
jerky response which can unsettle the
bike and even kick out the back wheel if
you're not ready for it. Setting the idle
high helps counter this, as does using a
higher gear, but it's still not ideal and
needs work. However, the R7 has a
much cleaner power delivery than the
old YZF, with its holes in the powerband that had the front wheel reaching
for the sky out of slower turns when
you gassed it up hard and the power
kicked in.
The R7 willlj.ft the wheel as you ride
the torque curve out of a slow bend, but
in general its power delivery is almost
too nice and user-friendly by World
Superbike standards, with a trong but
progressive response. [t pulls well from
as low as 6000 revs, kicks in at 8000 and
there's a strong, hard pull from just over
10,000 rpm all the way to the redline,
with no fall-off in power. The reduced
inertia of the stock titanium rods and
valves, coupled with the lightweight
tuftrided crank and forged 11.4:1 slipper
'pistons (still three-ring, though: Yamaha
tried two-ring pieces, says Miwa, but oil
consumption was too high) helps the
engine pick up revs quite fast - better
than the Suzuki, though not nearly yet
in the Honda class.
On the other hand, it's not a suddenaction light-switch like the '98 Kawasaki, even if it doesn't have the ZX-7RR's
appetite for revs, and the result is a
torquey-feeling bike that the stopwatch
confirms is faster around Jerez using a
gear higher for many 6f the turns than
you'd expect to with an in-line four.
rt doesn't pay to buzz the engine, but
to ride the torque curve instead. The
downside to this is that there isn't yet
the za p out of turns you need in the
superbike class these days, nor the topend power the R7 will surely need to be
competitive at the top level - and I think
that will only come with more revs, a
reprogrammed map for the EFI, and
maybe a higher compression as well as
more-aggressive cam profiles, all to narrow the powerband and get the Yamaha
punching out of turns like - well, like
the Honda does.
At the moment, it feels too much like
an ultimate road bike rather than a factory four-stroke GP racer - and believe
me, that's what it takes to get into the
winner's circle in World Superbike these
days. The bottom line of all this is that
the R7 shows huge promise for a bike at
the outset of its career, especially one
developed in such a short time. Miwa
says he didn't start work on it until just
over a year ago, after the Rl launch was
done and dusted - which perhaps
accotu:lts for Yamaha running late on
getting the one-off batch into production, given that the final specification
had yet to be established at the time of
the Intermot launch, and maybe.even
much later than that.
It's especially capable in terms of
overall packaging and chassis layout,
and has an engine with all the basics to
make the bike a serious Superbike contender, at any level. If it doesn't have
quite the mind-blowing, ground-breaking impact that the Rl delivered on its
debut, that can be attributed to a variety
of factors, chief of which is inevitably
the fact that it follows in the tire tracks
of its deservedly vaunted best-selling
big sister in showing how to repackage
an in-line four-cylinder sportbike - and
remember, too, that further development will surely follow once the bike
gets exposed to the white heat of competition. This is the first fuel-injected
sportbike that Yamaha has ever made,
itself a factor influencing the pace and
span of development.
For although this is the most sophisticated motorcycle Yamaha says it's ever
built, by the standards of the Superbike
class, the tuning-fork company is only
playing catch-up. The modern standards
for a fuel-injected competition fourstroke at which Yamaha has to aim have
been set not only by the Ducati/Aprilia
twins, but also by Honda, with the soonto-be-superseded RC45, and arguably
even Suzuki with the TLl000R and fuelinjected GSX-R750.
Much to its credit, the company has
taken up the challenge, and the R7 has a
good shot at being a contender in it
debut year on the race track - especially
in uprated works-team form, and with
Noriyuki Haga in thellOt seat, it certainly has the final ingredient to do so.
But, to be frank, there's an ulterior
motive for those of us on the other side
of the fence to wish Yamaha and Hagasan well - because if the curry-loving
cowboy of World Superbike racing succeeds in winning the World crown with
the R7, Yamaha will find it hard to resist
demands to build another batch of titletouting R7 street'bikes to celebrate the
fact. And that would be a Very Good
Thing, because this is a bike that, cost
notwithstanding, deserves to see more
of the world than just the inside of a
race circuit!
Cf/I
