A Decade of the GSX-R750
In an arena when updates or indeed model lives are seemingly measured
believe it or not, up until 1995 Suzuki produced its eleventh
GSX-R750. In that
regard, the marque's 750cc sportsbike is in a class of its own
- it's uncommon
for a touring bike to boast such a history, let alone a cutting-edge
Here's how the bike's evolved.
The very first mass-produced repli-racer (the GSXR750F) was released
to an eager
public on June 3, it was an immediate success.
The bike was based closely on the factory's Formula One racer,
and claimed an
impressive 100bhp at 10,500rpm, with a featherweight 176kg to
oil-cooled powerplant sported cylinder dimensions of 70.0 x 48.7mm
dimensions the first water-cooled GSXR, the WN, returned to in
The original GSXR had 29mm flatslide carbs, an alloy double-cradle
frame, 18-inch wheels with 110/80 and 140/70 tyres, and proved
heritage with a debut win in that year's Adelaide three-hour production
with Mick Hone Suzuki rider Rob Phillis aboard.
The GSXR750G remained virtually unchanged from the F. The GSXR750
was joined in 1986 by its new 130bhp GSXR1100 big brother, and
also the Limited Edition GSXR750 with dry clutch altered cosmetics
and longer swingarm. The latter was primarily a racetrack model
of which very few were made.
1987 My Version
The third-generation GSXR750 was the H. It had slightly different
(fairing lower in particular), a larger 21It tank instead of 191t
and a longer
swingarm. However, the engine was unchanged. The biggest criticism
of the first three models of the GSXR750 was a poor quality rear
The big change came with the GSX-R750J. A new short-stroke engine
introduced with 73.0 x 44.7mm dimensions, thinner piston rings,
bearings and big-ends to give a 38-percent stiffer crankshaft,
inlet valves and 1.Omm bigger exhaust valves (same as the 1100),
with higher lift, a 50 percent bigger oil-cooler, and 36mm constant-velocity
semi-flatslide 'Slingshot' carbs.
The chassis was also all-new with 43mm forks instead of 41 mm,
a stronger frame
with a 40mm shorter wheelbase, and the engine was mounted 25mm
became 17-inch with a 3.50 front and a 4.50 rear. A new slippery
improved aerodynamics, there was a remote front brake master-cylinder
was up to a claimed 112bhp at 11,000 rpm.
Drilling the carb slides certainly unleashed some extra ponies
racetrack only of course!) . The J wore a four-into-two exhaust
rather than the
F's four-into-one 'garbage can' muffler, and weight was up to
The GSXR750K's major change was limited to new exhausts with 'gold'
sleeves. The new system offered four degrees more cornering clearance
complaint with the J. weight remained at 195kg.
Suzuki also entered the Superbike 'homologation' war with the
GSX-R750RK in 1989
(known more commonly as the RR). It was designed to counter the
likes of Honda's
RC30 and Yamaha's OW01, but failed to grab the interest of private
owners to the
The R's engine returned to the 'long-stroke' dimensions of the
sporting exotic internals, 40mm CV carbs 120bhp and 187kg.
The GSX-R750L brought nearly as many changes to the GSX-R lineage
as did the
1988 J. Up front were the first readily available upside-down
forks on a
streetbike, there was a four-into-one chamfered exhaust, a steering
most importantly, a return to the long-stroke engine heralded
in the RK (70.0 x
The L also had 2mm bigger carbs at 38mm (but still 2mm less than
the RR), and
slight geometry changes with 25.5-degree rake instead of 24.9-
degree, and 100mm
of trail instead of 99mm. The rear wheel became the de rigueur
5.50 x 17.
Weight was down to 193kg and the smaller bore meant slightly smaller
increase the gas velocity. Power was up to 116bhp at 11,OOOrpm,
size was down from 12mm to 1Omm. The inlet cam stayed the same,
but the exhaust
sported 1.2mm less lift in the quest for more torque and a broader
Surprisingly, the redline was still 13,000rpm despite the longer
stroke, but the
new conrods used threaded cap bolts rather than through bolts
strength and lightness. There were lighter pistons, a lighter
large-capacity oil pump and a bigger curved oil-cooler.
This year brought some major styling changes to the GSXR, the
a 'shovel snout' and twin taillights. Internally, there were now
sliding rockers (rather than the forked rockers of the L) which
on the valve, with shim adjustment. Stronger valve springs were
the exhaust cam carried seven degrees less duration.
The M's chassis remained the same as the L, but claimed weight
was 15kg heavier
at 208kg. A more comfortable seat was a welcome addition, with
dropping from 795mm to 790mm as an added bonus.
After eight years of oil-cooling, the advent of the GSXR750W heralded
initial suggests) the arrival of water-cooling. As well as other
WN saw major changes to the engine room with downsizing of the
while retaining the M's 'long stroke' configuration.
Compression was up to 11.8:1, pistons were lighter, its airbox
was bigger and
the valve-stem diameters shrunk. All this saw an extra 2bhp extracted
WN, with claimed peak power now 118bhp at 11,500rpm and maximum
torque of 8.0kg-m at 9500rpm.
On the chassis side, the trademark frame was retained with larger
pentagonal-section tank rails and beefier castings at the steering-head
according to Suzuki yielding a torsional increase of 24 percent.
part however, was the built-up pressed asymmetrical swingarm.
Oh, and seat
height was down another 1Omm to 780mm.
More of the same for the P-model update of the first generation
GSXRs. Essentially just a cosmetic make-over with only colour
Much more than just the obligatory two-year update the '94 GSXR750WR
a multitude of engine, chassis and running gear changes. Along
with a new engine
mount for the magnesium (not aluminium) cylinder-head cover, the
WR also sported
new magnesium breather and ignition covers.
In a full engine redesign, last year's bike came with different
wider piston-ring grooves, spring-steel first piston-rings rather
stainless-steel, lighter conrods, a higher output Mitsuba starter
of the WP's Nippon Denso item, a smaller ignition rotor, stainless-steel
pipes (with thinner walls) rather) than carbon steel, and a plastic
cover instead of aluminium.
Other gearbox updates included a lighter primary gear, new counter-shaft,
four-dog second gear instead of three, revised and lighter fifth
gears, and a new clutch-release pinion, returning an all-up engine
of 2.35kg. Suzuki revised its claimed performance figures in 1994,
all the WR's engine updates the 194 bike claimed just 112bhp at
10,500rpm - some
6bhp less than its predecessor.
94's GSXR750 boasts a number of chassis updates also, including
diameter inner fork tubes with thinner walls (43mm instead of
diameter outer fork tubes (51.5mm instead of 52.5), revised fork
damping rates, 1mm thinner triple-clamps, revised rear shock spring
rates, a new swingarm, and a 25mm-diameter swingarm pivot shaft
20mm. A swag of running gear updates rounded out the '94 bike,
repositioned instrument cluster on the frame rather than triple-clamp,
battery and smaller-diameter headlights with no inner lens. These
some 2.55kg alone.
Other new bits included a centrally-mounted steering damper, six-piston
Tokico callipers rather than four-piston Nissins, drilled front
discs rather than
slotted, a 1mm thinner rear disc at 5mm, Dunlop D204 radials instead
59-series radials (with 180/55 rear instead of 170/60), lighter
modified spoke shape, and a narrower frontal area of fairing.
in some sections of frame led to a claimed 1.8kg weight saving
with no loss of
rigidity while total chassis weight reduction was a claimed 4.2kg,
total weight loss of 9.1 kg over the WP model (down from 208kg
Suzuki's GSXR750 series enters its second decade, with the '95
sporting a new exhaust system and jetting changes to claim peak
torque of 8.1
kg-m at 9500rpm and maximum power of 120bhp at 10,500rpm - some
8bhp more than its predecessor, but just 2bhp more (at 1,OOOrpm
less) than the 1992 WN.
With graphic updates and different front brake pad material.