BMW Z4 roadster

* All the car launches from Detroit * New Mercedes E-Class and Jaguar XFR * Toyota Prius, too...

BMW Z4 roadster

Sexual equality took a bit of a beating at the Detroit motor show and this time it was a two-piece metal folding roof doing the damage.

The new BMW Z4 roadster features said roof, which replaces the fabric version on the old model because its makers say its simplicity is more appealing to women.

Sure enough, the roof can be raised or lowered in 20 seconds, making it pretty handy - for a man or a woman.

Less controversially, there are other facets to the car that stand out.

For instance, it can be specified with adjustable suspension that allows the driver to choose between three settings that can lower the ride height by up to 10mm.

Drive Dynamic Control also give the driver the chance to alter the throttle and steering response, level of ride comfort, stability control response and on automatic or semi-auto cars, gearchange times.

Engine line-up
Three direct-injection six-cylinder petrol engines will power the new Z4, although high-output four-cylinder engines might be added later.

The range starts with the 201bhp 2.5-litre model (which BMW calls sDrive23i), which can reach 0-62mph in 6.6sec and has a top speed of 151mph.

CO2 emissions are 199g/km and average fuel economy is 33.2mpg.

The 3.0-litre sDrive30i has 254bhp and can reach 62mph in 5.8sec. CO2 emissions and fuel economy are the same as the 2.5-litre model's.

The range-topper is the 301bhp twin-turbo 3.0-litre sDrive35i. It can go from 0-62mph in 5.2sec and has an electronically limited top speed of 155mph. Fuel economy is 30.1mpg while emissions are 219g/km.

Six-speed manual and automatic gearboxes are available with all engines, but the top-end sDrive35i can also be fitted with BMW's seven-speed dual-clutch semi-auto transmission.

All models have BMW's Efficient Dynamics. This includes brake energy regeneration, a change-up indicator and tyres with reduced rolling resistance.

Inside and out
The new BMW Z4 is 148mm longer and 9mm wider than the model it replaces. BMW says this means more room for occupants and their luggage.

There are more stowage compartments in the cabin and the boot space is bigger than the old-model's too.

Prices have yet to be released, but expect the entry-level model to start at around 27,000 when the car goes on sale in May.