BMW Z21 'Just 4/2'

About this model

With the Tokyo Auto Show of 1995 looming, BMW wanted a cool concept car to show off its fun side. It may have been a coincidence, but Caterham is much-loved in Japan, and the BMW Just 4/2 concept seemed to channel much of the stripped-back sports car's philosophy. The car, codenamed the Z21 project, as BMW put it, was about 'enhanced driving pleasure on metalled roads'. Around this time, BMW had been introducing some interesting concepts, including an electric and hybrid city car that was way ahead of its time, and the Z21 was particularly interesting for driving enthusiasts.

Essentially, the Z21, developed by BMW Technik, was about offering motorcycle thrills in a four-wheeled package. This was a minimalist two-seater that had a similar concept to the Ariel Atom. The key to the concept was light weight and minimal driver distractions, with the focus on just pure driving thrills.

The car had minimal bodywork, and drivers had to wear a piece of headgear that looked like it had been left over after a Daft Punk concert. The wheels were open, apart from small mud guards, and BMW said that it emulated a formula racing car. Take one look at the Just 4/2, and the video above of it on the city streets, and it's hard not to think this could be one of the most fun cars ever created.

At the heart of the Just 4/2 is a four-cylinder power unit borrowed from the BMW K 1100 motorbike, which will spin all the way up to around 8,500 rpm. Considering the car only weighs 1,213 lbs, the 100 horsepower on offer would be plenty. The two-seater Z21 can hit 62 mph in roughly six seconds and has a top speed of 112 mph. The frame was made of a mixture of different types of aluminum, and the body panels were made from Kevlar. The car borrowed its brake discs from the M3 and had four-wheel independent strut suspension.

The car seemed ready to go. It was certainly roadworthy, with license plates fitted, as well as street-legal lights and bumpers. While special clothing and helmets were developed, the Just 4/2 did also have a number of contemporary safety features built into the design. There were airbags for both driver and passenger, as well as side-impact protection, showing once again that it had been thought out as a viable production concept. There was a tiny windshield that helped to direct air over the driver and passenger. BMW even tested this in the wind tunnel to prove that air would be deflected by this structure and be channeled over the cockpit and behind the car. Clearly, a lot of thought had gone into the Just 4/2 in the hope that it would at least make limited production.

Rather sadly, the car never made it to production. There seemed to be at least three built too, one blue, one dark red, and one silver. The reception to the car at the Tokyo show was strong too, which encouraged BMW to start simulated crash testing the model. Despite all this, the car never received the official production green light; however, possibly due to its niche appeal and a lack of profit in small production cars, although the engine, at least, would have been an easy, off-the-shelf part to manufacture.