Despite the fourth-generation Mazda MX-5 only going on sale last year, Nobuhiro Yamamoto, the car's program manager, has revealed some details about the next-generation model.

2015-Mazda-MX-5-3

Yamamoto told Autocar that the fifth-generation MX-5, which isn't due until 2021 at the very earliest, will attempt to shed more weight. Some of those savings will come through the adoption of more lightweight materials, including carbon-fibre.

Although carbon-fibre is currently expensive and typically reserved for upmarket sports cars and supercars, Yamamoto revealed that the Japanese car maker is working on ways to make it more affordable.

2015-mazda-mx-5-australia-launch-21

If Yamamoto and his team are successful with their weight loss program, the next MX-5 will also feature "a smaller engine, smaller tyres". So, it's possible that the next-generation car could feature a three-cylinder motor as its entry-level engine.

While the current car shrank in relation to the third-generation model, Yamamoto believes that "the size is right" now.

This is good news for adherents to the less-is-more faith, but Yamamoto did have some bad news for fans: the Speedster and Spyder concepts revealed at SEMA last year won't be heading into limited production as they aren't "feasible".