SUZUKI'S search for a new model
range with a European identity has resulted in the Katana series and,
in particular, the GS650G. Unlike the other models in the katana lineup the shaft-drive 650 is a
completely new bike, purpose-engineered as well as styled for the likes of
us poor souls this side of the Atlantic. It is less than radical in
appearance than its bigger Darth Vader stablemates but it still turns heads
and raises the occasional frown among the traditionally-minded. The brief given to Target Design, the Anglo-German freelance design
studio, commissioned to do the artwork, was to capture a racy type 'southern
European' look. In other words, Suzuki wanted to pass the Katana off as a
piece of Italian sculpture with oriental horse power.
Jan Fellstrom, a director of the company, won't object if you criticise
the bike's appearance as long as it provokes a definite reaction - and as
long as you do not dismiss the company's work as cosmetic. He wants you to love or loathe the bike. On no account will he settle for
a shrug of the shoulders when he asks your opinion. He stresses that the
machine has been economically designed to make the rider feel part of it. To a large extent, styling has been dictated by practical considerations.
The dual seat has been styled to act as a racing cradle with the rider held
in place between the fuel tank and rear seat hump which serves as a rather
precarious perch for the pillionist.
The rider's knees slot into cutaways in the petrol tank allowing a firm
embrace despite its generous 5.1-gallon capacity and bulbous appearance. The riding position itself is sporty, with semi rear-set footrests
pushing the rider forward to the low, flat 'bars. It is a long arm-stretch to the controls which makes the machine
uncomfortable to ride in slow-moving traffic but it feels good on the open
road when the wind resistence begins to press into your chest.
What lets the side down a little is the cheap, tarty finish. The
red-painted brake calipers and disc trims look particularly poor and the
Suzuki transfer on the tank has a nasty peel-off quality about it. By way of contrast, the four-into-two exhaust system has been
black-chromed and should retain its good looks far longer than the painted
variety. Black and red vinyl is used for the seat, while the lattice cast wheels
are white -painted with polished rims, it looks a bit garish - but people
notice you . . .
The result may not look all that Italian but it does have a certain
something and it's faster than everything in its class and most 750s. With a top speed of nearly 124mph, it is faster than the factory's own 1
6-valve GSX750 and is almost as fast over the standing quarter mile — with a
best of 1 3.2 seconds. Suzuki are the last of the Japanese manufacturers to step into the 650
class. Kawasaki set the ball rolling with their popular Z650, now offered in a
variety of different guises. Honda followed suit with their CB650 and Yamaha
moved in to the arena last year with their XJ650. BMW field the R65, Benelli the 654 and Triumph have just got back into
the act with the economy-minded single carb Thunderbird twin.
If you cannot find something to meet your requirements among that line-up
you must have some peculiar riding habits.
The Suzuki joins the list of machines to choose from as a head-on
competitor to Yamaha's celebrated XJ650 sporter. It mirrors many of the
Yamaha's general specifications and has the same kind of performance
characteristics. The four cylinder, twin cam Suzuki engine produces considerably more
torque than the Yamaha but still thrives on revs. It will pull intopfrom about3,500rpm butto keep it buzzing down those
back lanes you should not let the rev counter needle dip below 6,500rpm. A power output of 72bhp at the 9,500 red ling is claimed for the two
valve per cylinder engine, which features twin-dome combustion chambers (TDCC)
designed to improve efficiency. Both intake and exhaust flow is said to be
improved by the twin dome design, which improves combustion by creating
extra swirl inside the chamber.
Conical swish zones are machined into the head which provides a high
compression ratio despite the use of flat-crowned pistons Suzuki have
patents pending on the design.
Each cylinder is fed by its own 32mm CV Mikuni carburetor with the bank
of four instruments all sharing a common air filter situated under one of
the side panels.
Suzuki have cheated a little in their climb to the top of the 650
performance tree for the 62 x 55.8mm bore and stroke of the engine gives an
actual capacity of 673.8cc.
When it comes to insurance it means you are going to have to pay the same
rates as for a full 750 though that is also true of the XJ650 Yamaha and
Z650 Kawasaki which are both a few cubic centimetres bigger than their
actual designation figures suggest.
Petrol consumption during the test varied tremendously according to how
the throttle was used. Cruised at between 50 and 60mph on the motorway, the
Katana returned 62mpg but ridden hard that dropped to 31 mpg resulting in an
overall average of 44mpg.
Engine vibration makes the mirrors useless between 4,500 and 5,000rpm but
this rough patch clears up at higher revs.
Each time we write that some Japanese machine or other has been fitted
with the smoothest shaft transmission we have encountered, another model
arrives on the scene that is even better. Surely the state of the art at the
moment must be the enclosed shaft on the 650 Katana. It is impossible to
believe it is a shaft drive machine for the power pick up is almost
indistinguishable from that of a chain driven bike.
The unit is based on a modified version of the shaft fitted to Suzuki's
1000 and 850 models. In place of the conventional double countershaft the
new transmission system employs a spiral bevel gear for power transfer
mounted on the same axle-shaft as a mechanical shock absorber.
The presence of the shaft transmission cannot be felt through eitherthe
rear wheel or gearbox. Gear selection is so good that if you mess up a
change you have no one but yourself to blame. Doing away with one of the
transmission countershafts has helped reduce the length of the engine and
thus the length of wheelbase which is down to a squat 58.3 inches.
Dry the Katana tips the scales at 481 lbs and it feels even lighter which
is one of the main advantages 650s have over the largercapacity
heavy-weights. Handling is as good as that of the XJ650 Yamaha - which is
praise indeed - though at times the ride felt decidedly peculiar because of
what felt like an incompatibility of spring and damping rates on the rear
shocks.
Soft springs and harsh damping seemed to be the problem. On occasion the
rear suspension felt as if it was bottoming out when it was quite obvious
that it could not have been. A dial on the top of each unit provides a
choice of four damping settings and the springs can be jacked up to five
different levels of pre-load. After a good deal of experiment I found the
machine felt at its best with maximum spring pre-load and with the damping
dials at the number two setting.
The front forks also come with a choice of two spring pre-loadings
though, to be honest, the adjustment did not produce any noticeable
difference. Powerful, sensitive braking is provided by two 1 1 -inch front
discs but extra care has to be exercised with the identical rear brake to
prevent locking the wheel. The seven-inch headlamp provides a good night eye with a wide spread of
light on both dip and main beam. The instrumentation and switch gear are
also above reproach though failure to provide a passenger grab rail is an
unforgivable oversight. Like it or loathe it; either way Mr Fellstrom will be a happy man. BT.