The GSX Series is Suzuki's range of sport touring
motorcycles with four-valved engines. The earliest
GSX models were introduced in the early 1980s
to complement and later replace the two-valve
Suzuki GS series.
The current range of bikes by that name are
completely different designs that use derivatives
of former super sports engines from the early-to-middle
Among the earliest GSX models were the two-cylinder
GSX 250 and the GSX 400.
These Suzuki GSX models were the evolution
of the GS series of 2-valve per cylinder air
and oil cooled four stroke motorcycles. The
first 4-valve engines were produced for the
1980 model year, but retained the "GS" designation
for the US market until the release of the GSX-R
models in 1986 (1985 outside the US). These
GSX engines were based on Suzuki's "TSCC" (Twin-Swirl
Combustion Chamber) engine design, and shared
little with previous 2-valve models. The bike
called Suzuki Katana in the US had this engine
design, with designations of GSX-S, but has
little in common with the more modern GSX-F
Katanas, which are sport-touring bikes.
The early GSX four-cylinder engines are arguably
among the most reliable motorcycle engines ever
mass-produced, with the 1100cc and 1150cc engines
still very commonly used for drag racing and
hillclimbing competition in the US.
The TSCC engine was once again redesigned in
1983 with the introduction of a completely new
GSX 750, Suzuki's first modern mono-shocked
sportbike in both a naked (GSX 750E) and half-faired
(GSX 750ES) version. Although this bike received
solid reviews from testing magazines (and came
to be the testers' preferred 750 sport machine
for the year), its release was an ill-timed
duel against Honda's all-new V4 engine in the
form of the VF750 Interceptor.
The 1983 GSX 750ES was a ground-breaking model
in its own right, with air-adjustable anti-dive
forks, preload and compression-adjustable rear
mono-shock ("Full-Floater"), disc brakes at
both ends. Some of the futuristic features it
pioneered, like a fuel gauge, have since become
far more commonplace. Others, like the digital
gear indicator, turned out to be redundant marketing
ploys now considered retro and obsolete.
The bike disappeared from dealers in 1984,
to be replaced with the GSX 700 - a bike with
a de-stroked engine and minor cosmetic differences.
Minor tweaks included taller pistons and slightly
differing cam lift and timing. This plus a change
in factory gear ratios enabled Suzuki to produce
a motorcycle with near-identical performance
specifications to the GSX 750ES, even though
engine displacement was 15 per cent smaller
to satisfy the revised US import guidelines.
These included increased tariffs imposed by
the US government on all imported motorcycles
displacing more than 700cc (repealed in 1988).
This 50 per cent tariff was the reason behind
the glut of de-stroked 650cc and 700cc Japanese
motorcycles sold in the US in the mid-1980s
- unique to the rest of the world - and is also
the reason the GSX-R debuted in the US a full
year later than the rest of the world.
This work was mostly in vain for the US market,
however, as the GSX 750S Katana was completely
restyled in 1984, and the GSX-R 750 was released
abroad, painting a certain demise for the comparably
ho-hum ES. 1984 also saw an update in color
schemes for the GSX 750ES in the rest of the
world, with the naked "E" being dropped in favor
of the half-faired "ES" and a new "EF" model
with full upper and lower sport fairings (never
available as a factory option in the US).
The GSX 750E lived on for a few more years
abroad, but was eventually superseded by the
GSX-F series Katanas. The GSX-S Katanas were
also dropped from Suzuki's regular lineup, replaced
by the GSX-R series. The GSX 1100 lived on with
significant styling changes for the 1984 model
year, including a full-faired 124bhp monster
of a musclebike, the GSX 1100EFE (US: GS1150EF).
The larger bikes, although still sought-after
as classic superbikes, were also replaced by
the GSX-R and GSX-F Katana lineups, with significant
body styling changes, upgraded suspension and
braking components, and revolutionary frame
The GSX 750ES lives on in the market of previously
owned bikes as an affordable all-around motorcycle,
although with limited aftermarket and manufacturer
support for parts. The US-only GS 700 is still
fairly common there.
The GSX 750S (US: Katana) received an updated
engine for 1984, along with Suzuki's other big-bore
4-valvers. This is the engine that the first
Suzuki GSX-R Series bikes were based on.
Current GSX models are powered by derivatives
of this in-line, four cylinder engine with four
valves per cylinder, which is also used in the
Suzuki Bandit Series. They feature a combined
air-/oil cooling system called SACS (for 'Suzuki
advanced cooling system').
The current GSX series is produced as the GSX600F
and GSX750F faired sport touring models, now
in their second generations, and the unfaired,
twin-shock GSX 750 and GSX 1400 models.
The earlier GSX 1200 Inazuma was offered in
Japan only for a short time besides the GSF
1200 Bandit to cater for a clientele that went
for a more traditional styling and a somewhat
higher build quality. When it proved sufficiently
popular for overseas export, it was quickly
developed into the current GSX 1400.
These modern non-US GSX-models carry little
in common with their early to mid-eighties cousins
other than a distant ancestor in their powerplant.
The GSX 1100S Katana has been reissued as an
anniversary model several times for the Japanese
domestic market (where the GSX 400S Katana remains
a very popular model with styling straight from
the early-1980s), and Yoshimura has recently
released a small handful of fully re-worked
factory GSX 1100S Katanas for sale, requiring
potential buyers to win an essay contest before
being granted the opportunity to purchase one
of these rare beasts.
The GSX 250F is known as the Suzuki Across
and is notable as it has a rear petrol tank
and a helmet storage area where the petrol tank
The GSX1300R Hayabusa hypersport bike has nothing
in common with other GSX models but three letters
of its designation and the most basic design
parameters (number of wheels, cylinders, and
valves per cylinder).