The M15-2 was the first model from Suzuki to receive the Good Design Award from the Ministry of International Trade and Industry, proof that the company’s designs had attained an impressive level of excellence. The piston valve 2-stroke 1-cylinder engine generates maximum horsepower of 4.5 PS and has a top speed catalog rating of 80 km/h. Other changes from the previous model include updated designs for the seat and other parts.

The K50 and K50G are highly practical models with an agile design featuring elements such as a V-shaped frame and a rear fender separated from the frame. A good-looking fuel tank, oil tank, and other parts were adopted to match the new frame. The semi-upright handlebars with a larger pipe diameter are positioned higher and wider than the previous model, realizing an even more comfortable ride. A box-shaped seat ensures stable ride comfort. These models are also equipped with a new side stand convenient for short and quick parking. In October of the same year (1969), the model-changed K50G debuted with a new forward-tilted engine. This engine generates maximum torque of 5.1 N·m (up from 4.12 N·m) and substantially higher torque in low- and mid-rpm ranges, which made it possible to change the transmission system from a rotary 4-speed automatic to a 3-speed for easier operation. However, the rotary 4-speed automatic transmission was re-adopted in 1973.

The styling of the K50 was completely updated from the previous model by changing the shape of the fuel tank and frame cover, while retaining the same well-received air-cooled 2-stroke 1-cylinder engine that generates maximum power of 4.5 PS. The appearance of this long-selling model-changed K50 was left untouched for 27 years until it was withdrawn from the market in 2005.