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YAMAHA GX Models/Series Timeline, Specifications & Photos

Generations: 3
First production year: 1976
YAMAHA GX 250 photo gallery

The Yamaha GX 250, also known as the XS 250 in other markets, was a middle-class motorcycle introduced by Yamaha in 1977 as the first 250cc four-stroke model, alongside its bigger brother, the GX 400 version.

Compared to its larger sibling, the GX 250 was identical, with only minor differences, including the rear wheel size, which was slightly smaller, as well as the engine displacement, which was 150cc smaller.

Visually, the bike was identical to the larger model, packing standard features, such as a round headlight with instruments mounted on top, a square fuel tank, a one-piece dual seat, side-mounted rear shocks, a dual exhaust system, a side stand, and a wire-spoke wheels.

The bike's suspension system comprised a telescopic fork on the front, and dual-side mounted shock absorbers on the rear, delivering optimum suspension performance and handling.

The braking power was achieved by a single brake disc on the front wheel and a single disc on the rear wheel, providing optimum stopping power.

As for the power figures, the 1978 Yamaha GX 250 had its soul brought to life by a 248cc four-stroke air-cooled parallel-twin engine mounted underneath the fuel tank, delivering 25 hp with maximum strength at 9,500 rpm and 19 Nm (14 lb-ft) torque at 8,500 rpm.

The small motorcycle was driven by a six-speed gearbox with a wet multi-disc manual clutch. The rear wheel was linked to the transmission with a final chain drive.

full description and technical specifications
YAMAHA GX 400 photo gallery

The Yamaha GX 400, also known as the XS 400 in other markets, was a middle-class motorcycle introduced by Yamaha in 1977 as the first 400cc four-stroke model, alongside its smaller sister, the GX 250 version.

The bike featured a cafe racer style, reminiscent of cafe racers at the time, using a square fuel tank. Later models were updated with a teardrop-shaped fuel tank and an up-handle design.

In the aesthetic department, the bike packed a round headlight on the front with instruments mounted on top, a square fuel tank, a one-piece dual seat, a dual exhaust system with a muffler mounted on each side, and wire-spoke wheels.

In 1978, when the cast alloy wheels were approved, the manufacturer quickly installed the new wheels on both GX 400 and GX 250, changing their names to GX 400SP/250SP. The tank graphics were also changed, driving up the price.

Underneath its fuel tank, the 1977 Yamaha GX 400 had installed a 391cc four-stroke parallel-twin air-cooled engine that delivered an output power of 37 hp with a peak force at 8,800 rpm and 33 Nm (24 lb-ft) torque at 8,000 rpm.

A six-speed transmission with a manual wet multi-disc clutch handled the bike's power and sent it to the rear end through a final chain drive.

The bike packed a telescopic fork on the front, twin side-mounted shock absorbers on the rear, acting as suspension, and a single brake disc on both front and rear, serving as stopping power.

full description and technical specifications
YAMAHA GX 750 photo gallery

The Yamaha XS 750 and XS 850 were a line of motorcycles powered by a three-cylinder engine and manufactured by Yamaha from 1976 to 1981. It was voted by Motorcycle News readers as the "Machine of the Year."

In 1976, the Japanese motorcycle manufacturer launched the Yamaha GX 750 (known in Japan), and unlike other models sold worldwide, the GX version was fitted with wire-spoke wheels instead of cast alloy ones. The XS 750 became the export name.

In the visual department, the 1976 Yamaha GX 750 was fitted with standard features, such as a round headlight, a one-piece dual seat with a passenger grab handle, a dual exhaust system, a side stand, and lightweight wire-spoke wheels.

In the performance department, the 1976 Yamaha GX 750 had installed a 747cc four-stroke three-cylinder air-cooled engine underneath its fuel tank, boasting 67 hp with a peak force at 7,000 rpm and 62 Nm (46 lb-ft) torque at 6,500 rpm.

A five-speed manual transmission fitted with a wet multi-plate clutch handled the bike's power and sent it to the rear wheel through a low-maintenance final shaft drive.

The bike packed a telescopic fork on the front paired with a single brake disc and twin side-mounted shock absorbers on the rear with a single brake disc mounted on the wheel, providing optimum suspension performance and handling.

full description and technical specifications