This week has seen both the Tokyo and Los Angeles Motor/Auto Shows. While LA saw the latest BMW 4-Series Convertible in the flesh for the first time as well as the latest Porsche 911 Cabriolet (which as you might expect would take a serious enthusiast to tell apart from the 2013 model), the really interesting sights were at the Japanese show.

Daihatsu Kopen

Daihatsu Kopen interior

First off is the predicted renaissance of micro roadsters known as Kai cars. The long awaited Daihatsu Copen replacement is now looking like reality and could be on sale as soon as 2014. Called the Daihatsu Kopen, it comes in two versions – a Rmz traditional sports car (above) and a more chunky Xmz SUV-look roadster (below). Power comes from a 660 cc three-cylinder engine with a CVT paddle shift gearbox. While officially still a concept the design looks to be close to completion with a main structure beneath the removable resin body panels, as displayed here, which would allow easy customisation should the owner want to change the look or colour.

Daihatsu Kopen Xmz

Daihatsu Kopen chassis

Honda also showed their compact kai roadster, the S660 which again is a concept that looks very much like a production reality. This car follows Honda’s futuristic design style both inside and out with strong influences from the brand’s 2011 EV-STER concept car. While the name suggests a standard kai class 660cc turbocharged petrol engine, there may be an electric motor or two in there as well. So far |Honda aren’t letting on.

Toyota GT86 Convertible

Moving up in scale a little, Toyota displayed two convertible concepts. First is the FT-86 drop-top version of the Toyota GT-86 sports coupe (sold as the Scion FR-S in North America). There has been much speculation over whether this convertible car will make production but it would appear that Toyota is still undecided and testing the water in Japan.

Toyota Aqua Air

The Toyota Aqua Air is a convertible hybrid based on the Aqua hatchback (Prius C in North America) which brings a much needed breath of fresh air to the earnest Prius hybrid. An affordable low carbon convertible seems an intelligent move making hybrid cars more exciting and providing an environmentally ‘friendly’ alternative for drop-top fans.

Nissan’s convertible contribution comes in the form of the BladeGlider – a road going sports car based on technology developed in the Deltawing racing car. While the BladeGlider looks like a wild and impractical concept, the car represents one of the biggest developments in car design for decades. Based on a theory of moving weight to the rear of the car and narrowing the front track and tyre contact area resulting in a drop in drag along with handling improvements thanks to the reduced load transfers across the car.

Nissan Bladeglider concept

While the theory appears to work, in practice Nissan have a big job to make it a road car reality. The BladeGlider is the first step towards this and winning public opinion, positive road test reports and track results will be vital to all that potential becoming a commercial success.