Suzuki GSX1100E, Superb Classic Four !

Suzuki really stirred up the pot with the GSX1100E of 1980, if you wanted sphincter-searing acceleration at a knock down price the GSX had it all covered.

Suzuki GSX1100E

Suzuki sat back to watch the combined efforts from Honda, Yamaha and Kawasaki flounder in its wake until (with the opposition closing the gap) the EFE was born in 1984, and it had no intention of taking any prisoners.

The GSX1100E motor is astoundingly simple : it has Inline four cylinders, five speeds and one destination, the top of the heap. It builds on the principles established as far back as the GT750 water-cooled two-stroke. The transmission layout is very similar, this design carried on to the GS750, the GS1000 and then the GSX1100.

The crank and gearbox input and output shaft centres are shared with its four-stroke buddies, the basic design of the camshaft drive chain and tensioners is a simple evolution of its forebears. That’s the trick that Suzuki pulled off for the umpteenth time, no crazy ideas, just good old simplicity and brilliance of design that don’t hanker after adulation or adoration, but that does tend to follow after the first time you crank open the throttle on one!

Around the time that the 100 horsepower gate swung open the Big 4 were all capable of producing bikes that could transcend this hurdle but there were many problems which befell them. There were chocolate cams and recalcitrant camchain tensioners and second gear selectors that did and then didn’t.

Big problems emerged when bikes exceeded 200 kilos and 100 HP. But the EFE tore up that risk assessment, and then proceeded to tear up the quarter mile with Pee Wee Gleason on board in mid 10 second order at close to 130mph. These numbers were pretty impressive back then... wait a mo, they’re pretty impressive now ! The reason for this massive rush of ballbusting torque is simple, the development that Suzuki did on the GSX1100 was just the starter, when the main course rolled up the EFE had a totally sorted carb/cam/valve/piston/exhaust combo.

Suzuki GSX1100E

The carbs were just big enough to allow in excess of 110 HP but small enough to encourage high intake velocity which gave near perfect atomisation of the intake charge, hence great midrange and throttle response regardless of gear position or the position of the tacho needle.

The cams, likewise didn’t need crazy lifts or excessive spring pressures to get the job done, just enough was okay thanks. The intake valves increased in diameter by 1mm from 27 to 28mm but the exhaust stayed the same at 23mm. The 76mm pistons are lovely, tough with slim rings, the forgings (not castings) are neatly ribbed under the crown for strength and heat dissipation.

Yet again Suzuki pulled a rabbit out of their hat here, generally speaking, alloys used for casting use a higher proportion of silicone in their mix. This reduces the coefficient of expansion thus allowing tighter piston to wall clearances, the ART alloy used for the forged pistons still allows minimal clearances which were previously unheard of. It might be worth mentioning here that Suzuki’s GS1000R F1 racebikes used pistons crafted by Fred Hadleigh at Omega in the West Midlands.

What is truly amazing is the similarity twixt the Omega design and the later factory pistons as installed in the EFE, and yes I am aware that the 1000R was a two-valver and the GSX has four of ’em, the design clues I’m referring to relate to the internal design as opposed to the piston crown.

Vincenzo Piatti pioneered a fully machinable combustion chamber which optimised compression, valve size and flame travel to burn the precious charge in the most efficient way possible. With this single refinement the GSX and its first cousin, the EFE, stomped off into the distance, any gear, any revs, anytime.

Given the fact that there was so much of everything available at relatively low engine speeds, riding an EFE was rapidly recognised as a good way to spend a Sunday afternoon, they start easily, will run on just about any kind of fuel without complaining, they don’t get hot, they have a huge alternator to fire up the similarly huge headlamp and they don’t wilt after a tankful of abuse. Even 30 odd years after its release the EFE has a loyal band of followers that can’t get enough of that torque-nami, sure they dress ’em up with USD forks and trick swingarms (like Colin Peabody’s lovely bike here) but the stuff that sits under that crackle black cam cover is sacrosanct, the beating heart of a true classic.

The architecture that was laid down back then has not changed, particularly in drag racing circles (or should that be straights?) Whatever, EFE-based bikes, with a few tweaks are running over three seconds quicker down the 1320 than Pee Wee ran at Orange County International Raceway all those years ago, sure they have multi-stage lock up clutches and trick auto boxes and digital everything but underneath are still the rock solid design concepts that haven’t been improved on. With capacities of up to 1600cc by virtue of big pistons and stroker cranks it’s unlikely there will ever be a more appropriate basis for this kind of lunacy as slimmer, modern engines afford less room to grow.

So we have a great spread of everything, reliability, simplicity, strength and power. Can’t last can it? And it didn’t, fuel injection, water cooling and Nikasil plated bores changed what had previously been simple and pure into, well, complicated, and we don’t really do complicated. So the EFE continues to co-exist with its younger siblings, I wonder how things will be in another 30 years? I know which one my money’s on.

Suzuki GSX1100E Specifications

Manufacturing : Suzuki Motor Co.

Model : GSX1100E (EFE)

Production Year : 1972 - 1976

Engine : 4-Stroke, Oil-Cooled, Inline 4 Cylinder DOHC 16-Valve

Bore x Stroke : 72 x 66 mm

Cylinder capacity : 1.074 cc

Fuel Supply System : Carburetor Mikuni 34mm

Compression ratio : 9.5: 1

Transmission : 5 - Speed

Ignition : CDI

Starter : Electric Starter

Max Power : 100 HP @ 8.700 RPM

Max Torque : 85,3 N.m @ 6.500 RPM

Top Speed : 227 Km / h

Dimensions L x W x H : 2.255 x 760 x 1.190 mm

Wheelbase: 1.510 mm

Ground Clearance: 152 mm

Dry weight : 237 kg

Fuel tank capacity: 19 L

Frame : Tubular Steel Double Cradle

Front Suspension : 37mm Kayaba Telescopic Fork

Rear Suspension : Kayaba Dual Shock

Front Brakes : Dual Hydraulic Disc 275mm, 2 Pots

Rear Brakes : Single Hydraulic Disc 275mm, 2 Pots

Front Tires : 3:50 - 19

Rear tires : 4.50 - 17