The latest in BMW's roadster family has been revealed — all-new Z4 arrives next year.

The Z4 is the first car in BMW's 75 years of roadster heritage to come with a two-piece, electro-hydraulically operated Retractable Hard-Top roof that can be raised or lowered in 20 seconds. The new roadster is also the first vehicle to be offered with Adaptive M Suspension. Electronically controlled dampers offer three different configurations and lower the ride height by up to 10mm for a more dynamic drive. By way of comparison, the Sport+ setting of the new car is comparable to the outgoing Z4's standard ride comfort level.

The standard Drive Dynamic Control function is another first and allows the driver to alter the throttle and steering response, level of ride comfort, Dynamic Stability Control response and, on automatic or Double Clutch Transmission cars, gear-change times.

Powering the new BMW Z4 is a choice of three six-cylinder powerplants. The range flagship is the current International Engine of the Year-winning 3.0-litre twin-turbocharged engine. Producing 228kW at 5800rpm, the BMW Z4 sDrive35i powers its way from zero to 100km/h in 5.2 seconds (5.1 seconds for a Double Clutch Transmission-equipped car) and on to an electronically-limited top speed of 250km/h. The twin-turbocharged 2979cc engine produces 400Nm of torque from 1300rpm while consumption is 9.3l/100km and CO2 emissions 219g/km.

Joining this model in the launch line-up are the Z4 sDrive23i and the Z4 sDrive30i. Both use the same engine but with varying capacities. The 2497cc entry-level Z4 sDrive23i produces 152kW at 6400rpm and 250Nm of torque from 2750rpm. This equates to a zero to 100km/h time of 6.6 seconds and a top speed of 241km/h.

The BMW Z4 sDrive30i comes with a 2996cc powerplant offering 192kW at 6600rpm and 310Nm of torque from 2600rpm. The six-cylinder engine records a zero to 100km/h time of 5.8 seconds and an electronically-limited top speed of 250km/h.

Transmitting the power to the road in all three Z4s is a six-speed manual gearbox as standard.

All of the latest BMW Z4s come as standard with facets of BMW's EfficientDynamics programme. Technologies that improve engine performance while enhancing economy and cutting emissions include Brake Energy Regeneration, Electric Power Steering with Servotronic, Reduced Rolling Resistance Tyres, and Optimum Shift Indicator on manual transmission cars.

More space

The new BMW Z4 is larger than its predecessor measuring 148mm longer at 4239mm and 9mm wider at 1790mm, and this results in greater interior space and luggage capacity. With the roof up, headroom has been increased by 44mm while the greater car width and design enhancements have led to 20mm more shoulder room and 43mm more elbow room.

For the first time on a BMW Z4 there is a bespoke storage facility located behind the driver and passenger seats. This approximate 15.5-litre single compartment stretches the width of the car’s interior and features netting to hold the contents in place. It can be complemented by an optional Storage Package that adds further stowage capacity.

The unique roof construction of the BMW Z4 creates a boot that varies in capacity from 180 to 310 litres — large enough to stow a full set of golf clubs. For the first time on a BMW Z4 customers can specify a through-loading system for additional storage capability. A hatch between the two seats permits a second full set of golf clubs to be carried.

Driver visibility in the BMW Z4 has also been improved. All round visibility is up by 14 percent while, courtesy of the four electric windows creating a larger glasshouse, side visibility is up 40 percent. The Retractable Hard-Top roof features a glass rear window and this too improves visibility by 52 percent.

BMW's latest generation of iDrive makes its first appearance on a Z4. The BMW Professional Multimedia Navigation system features a hard disc drive capable of 12Gb of audio file storage.