The Z4 Roadster's front suspension is a spring strut structure with forged aluminium track control arms and twin-sleeve gas-pressure spring struts. The rear suspension features reinforcement bars and thrust plates in the underfloor, connecting the front of the rear bulkhead onto the body under sills on both sides. The central arm rear axle also features twin-sleeve gas pressure dampers for optimum road holding and comfort.

An optional Sport Suspension package lowers the ride height of the car by 15mm and offers more focused ride characteristics for the enthusiast. The same suspension arrangement is part of the standard equipment for Sport models.

The Z4 M Roadster has its own unique suspension ride height with spring and damper compliance based on the 'standard' car. It also uses the same powerful braking system of drilled and vented discs from the legendary BMW M3 CSL.



Safety and Technology

The Z4 has the most advanced form of traction control system currently available in the world - Dynamic Stability Control+ (DSC+). Building on the already accomplished DSC system, DSC+ offers five further safety enhancements:

- Brake Pre-tensioning shortens stopping distances by priming the brakes if the driver instinctively lifts off the accelerator in preparation for an emergency stop.
- Brake Drying improves braking performance in the wet by periodically gently applying the pads to the discs. In wet weather conditions, a film of water can build up on the disc hindering stopping power but this slight braking action removes this film and ensures optimum retardation.
- Hill Start Assistant allows the driver of a manual transmission car to pull away smoothly on a gradient without having to balance the clutch and the throttle. Brake pressure is maintained for the time it takes to move the foot from brake to accelerator, preventing the car from rolling backwards.
- Fade Compensation can apply additional braking without any extra effort from the driver. Following very spirited driving the brakes may experience some fade due to excessive heat build-up. However, Fade Compensation means the pads still bite the disc for optimum stopping power.
- Soft Stop contributes to a smoother journey for all occupants. A small proportion of braking pressure is released as the car comes to a standstill, minimising the potential for a sharp, halting stop.

Other safety and technology benefits fitted as standard to the new (non-M) Z4 include Run-flat tyres and a Tyre Puncture Warning System (TPWS). The Z4 M Roadster uses a combination of TPWS and M Mobility system. BMW's M division remains committed to 'standard' tyres that contribute to the extreme performance levels preferred by its customers.

BMW Assist comes as standard for a BMW Z4 specified with the optional Professional navigation system and Bluetooth phone preparation. In the event of an accident, the driver can use BMW Assist to make contact with the emergency services. The system also broadcasts a pinpoint map location via satellite to aid recovery. In the unfortunate event of an accident resulting in airbag deployment, BMW Assist automatically contacts the emergency services. BMW Assist also provides a similar level of assistance with regards to breakdown cover courtesy of the automatic vehicle locator function.



Market and Marketing

Research into Z4 owners shows the car is enjoyed as more of a performance roadster than the Z3 it replaced. BMW's own customer research, based on buyers of the original Z4, has shown that the two main purchasing drivers were style and on-road performance.
To underscore the more masculine nature of the Z4, men account for more than two thirds of buyers, while the biggest age group of Z4 owners falls into the 30-39-year-old category. The average annual income of a Z4 owner's household is Pounds Sterling 72,000.

previous page | go to page 11