1982 Suzuki GS1100E on
the Pacific Coast Highway, 2004. While one of
the best performing sportbikes of their era,
the GS series bikes are still good all-around
machines as they approach their vintage years.
From 1976 to 1987, Suzuki produced its GS
line of motorcycles.
These motorcycles had air-cooled in-line
DOHC engines with two or four cylinders, two
valves per cylinder and displacements between
250 and 1100 cc. The four-cylinder variants
are considered to be Universal Japanese Motorcycles.
When introduced in 1976, Suzuki offered the
GS400, GS550 and GS750 models.
Engine design considerations
Earlier Suzuki motorcycles were two-stroke.
This was something of a liability for Suzuki
at the time, for while their two-stroke line
of motorcycles was well regarded, impending
air quality legislation in the US would see
two stroke motorcycles banned for sale there
due to their notoriously filthy emissions.
A short reprieve for the two stroke would
occur in the 1980s when Yamaha sold a much
more environmentally friendly RZ350 motorcycle,
but the era of the two-stroke street motorcycle
had passed by then, at least in America. Weird
designs like the Wankel-engined RE5 were clearly
not the answer. This left Suzuki in a bit
of a bind. If they were to compete effectively
in the largest motorcycle market in the world,
they needed a four stroke model, and fast!
Early GS four-cylinder models
Their solution was to virtually copy the
900cc Kawasaki Z1 engine and release it as
the 750cc GS. It was an immediate hit, boasting
a top speed approaching 130mph, excellent
handling and handsome lines. The engine shared
the Kawasaki's trait of being virtually indestructible,
and thrived on high speed work. The arrival
of the larger GS1000 put it in the shade somewhat
in terms of all-out performance, but it remained
a popular and capable motorcycle in its own
right.
The GS1000, on the other hand, proved that
the Japanese could build a big, fast four
cylinder motorcycle that actually handled,
something Kawasaki never quite managed with
the fast, but loose handling Z1. It likewise
inherited the Kawasaki's stout nature, and
the two motorcycles were destined to meet
head to head on drag strips for years to come.
Heavily modified from stock, these motorcycles
nevertheless proved reliable, while putting
out several multiples of the horsepower they
were originally designed to produce.
The GS1000 sported a few new ideas, the rear
suspension on the EC model and the front forks
had the facility of an air valve in which
(small) amounts of air could be added to change
preload. The GS1000S had a small bar mounted
fairing with extra clocks mounted, plus larger
carburetters, taking power to 90PS. The GS1000G
was more of a touring bike with shaft drive,
which added a fair bit of weight. The arrival
of Honda's exotic six cylinder CBX stole the
GS's thunder for a short while, but a redesign
of the engine from an eight valve to a sixteen
valve (as the GSX1100) improved its performance
substantially, without compromising its reputation
for reliability in any way. It soon had the
beating of the CBX, which slowly mellowed
into a sport-touring motorcycle with fairing
and panniers before disappearing altogether
from Honda's lineup.
Reliability
Perhaps the only Achilles heel in the GS
design was an overly fussy electrical system
which was prone to failing quite spectacularly.
The dreaded regulator/rectifier break down
led to much pushing and sweating for unlucky
GS owners. If fortunate, the regulator/rectfier
would be the only casualty. If unlucky, the
entire charging system was wrecked (along
with every bulb on the bike), leading to an
expensive repair. The smart GS owner replaced
the original Suzuki parts with stronger aftermarket
items (usually at a lower cost), although
regulator/rectifiers from some Honda models
have been successfully adapted to cure the
problem once and for all (Honda Superdream/450
Nighthawk units).
A thorough discussion of all GS Suzuki would
require its own reference book. Suffice it
to say, the GS line of motorcycles was one
of the most versatile, durable, powerful,
and comfortable designs ever produced by any
Japanese motorcycle manufacturer. From 125cc
to 1100cc, there was not a deficient model
in the entire line.
As the flagship of the Suzuki line, the GS
series was succeeded in the early 1980s by
Suzuki's GSX motorcycles with four valves
per cylinder.
The only "surviving" member of the GS series
has a bored GSX 400 engine with a redesigned
two-valve head. It is still produced as relatively
affordable entry-level bike, the GS500E (naked)
and GS500F (fairing). In Japan and possibly
other jurisdictions, it is offered with 400
cc due to restrictions imposed on learners.
