Launched as Suzuki’s flagship superbike on the show circuit in 1971, the GT750 wasn’t a fire-breathing monster like the Kawasaki Mach IV/H2 triple, but instead proved to be a pleasant touring bike, comfortable to ride, with a roomy seat and a handy grab rail.
The first model, known as the GT750J, appeared in the UK in 1972, with a claimed 67bhp three cylinder, water-cooled engine, drum brakes front and rear and a radiator cowling painted to match the tank, four exhaust exit pipes and very large louvred side panels.
It’s a fairly easy job to spot a J model if you find one, but they are extremely rare in Britain – most of the J model’s production run was exported to the North America.
1972 was a big year for Superbikes in Europe and the USA, with new or revamped models coming from various manufacturers. Road tests of the time pitted the big Suzuki against the Norton Commando, Triumph Trident, BSA Rocket III, Honda CB750 and Kawasaki H2. It rapidly became obvious that the Suzuki wasn’t sweet-handling like a Commando, or faster than a Kawasaki H2 over the quarter mile. But the GT750J was a surprisingly torquey bike to ride, making its peak power at 6500rpm – low for a two-stroke – and nowhere near as greedy for fuel as the Kawasaki triple. A well set up GT750 can return 40mpg on a steady run, which is equal to some modern four stroke 750s in the 21st century.
Like Kawasaki, Suzuki developed the GT750 from its 500cc two stroke models, although it’s fair to say both owed a huge debt to DKW who were racing two-stroke triples back in the mid-50s. Like DKW, Suzuki attempted to improve the scavenging process inside their two-stroke engine with the GT750 boasting Suzuki Recycle Injection System – or in plain terms, a method of reducing the amount of unburnt fuel/oil from the crankcase chambers. The GT750 also had linked exhaust pipes and curious black painted cones on the J model. Most of the J models were painted in Candy Lavender or Candy Ochre, a kind of metallic gold.
There was extra chrome plating added on the K model for `73, along with a brace of 295mm front disc brakes on the front wheel. This one change arguably made the GT750 a Superbike contender, as Kawasaki and Honda both had one disc on their flagship models. The four pipe exhaust arrangement survived on the K model for `73. New colours for `73 included a blue model and all the K bikes feature a white stripe on the fuel tank.
The L models of 1974 can be recognised by the thinner pinstripe paintwork on the gas tank, plus a switch to a different shade of metallic blue. The L model also received exhausts which lost their connecting balance pipes, plus new carbs, new airbox, a gear position indicator, different throttle cable arrangement, new side panels and seat. There were two colour options, Flake Blue and Flake Orange.
1975 saw the M model appear, something of a stop-gap model featuring some tweaks to the engine to squeeze a tad more power from it and the benefits of a new, closer fitting exhaust pipes which were aimed to improve ground clearance.
Perhaps the best selling GT750 model in the UK was the A version, which was heavily advertised with Barry Sheene fronting the Heron Suzuki ad campaign. The A model was available in metallic orangey-red or blue, with lashings of chrome all over the bike; side panels, mudguards, mirrors, grab rail – you need to buy 5 gallon drums of Solvol to keep a GT750 A/B model shiny.
The 1976-78 model GT750s make the most practical classics today. They have CDI rather than points ignition, lack the three-cable throttle set-up on the early bikes and the higher ratio gearbox makes it an even more agreeable cruiser/tourer.
Examine the seat pan, clocks console and mudguards carefully – all hard to obtain now.
Check that nobody has welded up leaky pipes or junctions around the radiator and exhausts.
It really shouldn’t be running on two cylinders, then three when warm – could be a blown crankcase seal, which is a pain to replace.
Suzuki GT750 Technical Specification
- Liquid cooled, three cylinder, 738cc, two-stroke.
- Gears; 5 speed
- Fuelling; X3 32mm CV carbs
- Peak power; 67bhp ( claimed )
- Peak torque; 55 ft/lbs ( claimed )
- Chassis; Steel tubular frame, 35mm forks, twin shock rear suspension
- Brakes; Twin 295mm front discs, 2 piston calipers, single 200mm rear drum.
- Fuel consumption; 40mpg average
- Dry weight; 505lbs dry
1970 – GT750 concept model at Tokyo Show
1971 – First J series bikes shipped to North America and Japan
1972 – J models imported to UK by Heron Suzuki, probably less than 500 models.
1973 – K model appears. New paint, twin front discs
1974 – L model features no link pipes on exhausts, new paint/graphics, gear indicator, throttle cable, airbox, carbs.
1975 – M model, new tucked-in exhausts. Some European markets only got the L series upgrades on their M series bikes. 70bhp claimed from engine, new gear ratios, improved porting to reduce emissions. New colours/graphics.
1976 – GT750A model appears in large numbers in UK, red or blue colours. Possibly over 1500 examples imported
1977 – B model launched. Cosmetic changes include black side panels, new front mudguard and headlamp. Some examples sold at discount prices and registered in 1978-79 as GS750 proved more popular in UK market.