Open-topped motoring comes to the 1 Series range.
BMW UK has announced the first details of the new BMW 1 Series Convertible, the world’s first premium convertible in the compact segment.
Powered by four- and six-cylinder engines, from the entry-level 143hp 118i Convertible to the ‘bahn-storming 306hp 135i Convertible, the open-topped 1 Series uses elements of BMW’s EfficientDynamics programme to deliver high-performance, economical and low-emission, roof-down motoring.
The Convertible is the fourth derivative of 1 Series to be launched and will carry over much of the styling and technology from the recently launched Coupé model. The obvious addition is an electro-hydraulic fabric roof that opens or closes in 22 seconds, and at speeds of up to 25mph. The convertible roof is available in classic black, beige or, as a world first, an innovative anthracite silver fleck which is a fabric material interwoven with fine shiny metallic fibres.
Exterior design – elongated and elegant.
Viewed from any angle, the BMW 1 Series genes are clear in the new Convertible. From the front, BMW’s trademark double headlamp unit and large kidney grilles dominate. In profile, the relationship to the Coupé is clear. Both cars share a virtually identical silhouette, classic long bonnet and short overhangs.
The distinctive, horizontal shoulder line runs from the front of the bonnet, through the long, frameless doors, and onto the end of the boot lid. It is complemented by the 1 Series’ typical lower swage line and contoured sill, both designed to visually elongate the appearance of the car. From the rear, the boot lid finishes in a discrete lip spoiler that houses the integrated third brake light and typical L-shaped rear light clusters use LED-powered light conductors.
Also in common with Coupé models, purchasers of 135i Convertibles receive the M Sport aerodynamic package as standard. Visually striking and dynamically effective, the 135i Convertible features a redesigned, sporting front valance with large air intakes assisting engine breathing and brake cooling.
Re-profiled sill panels and a rear diffuser integrated into the rear bumper add to the car’s sportiness. The 135i Convertible also features 17-inch light alloy wheels and six-pot brake callipers on the brakes (two-pot on the rear).
Interior design – options from further up the range.
The interior of the new BMW 1 Series Convertible features stretched horizontal lines that visually dominate the cockpit. With space for four occupants and 305 litres of boot space with the roof up (260 litres with the roof down), there is plenty of room to convey occupants and luggage over the longest of journeys.
In line with the recently launched 3 Series and 6 Series Convertible, owners of 1 Series Convertible models benefit from SunReflective Leather Technology whenever leather seat coverings are specified.
BMW is the only manufacturer to offer this innovative technology that uses ‘cool pigments’ during production to reflect infrared rays of sunlight. This reduces the surface temperature of the seat surfaces by up to 20 degrees Celsius when compared to conventional leather upholstery.
Also carried over from the new BMW 3 Series Convertible are specific settings for the air conditioning system. Alongside the standard ‘gentle’, ‘medium’ and ‘intensive’ settings, the system recognises when the roof has been opened and defaults to a ‘convertible’ mode. In this situation, the ventilation control reacts less to the interior temperature and more to the outside temperature and sunlight factors to establish the intensity of the ventilation supplied.
Safety is of paramount importance for BMW and the 1 Series Convertible comes with an additional tier of protection in the event of a roll-over. A sensor registers an imminent danger and, alongside the relevant airbag deployment, two roll-over bars extend from behind the rear seats in a fraction of a second to protect the safety cell.
EfficientDynamics – balancing power, economy and emissions
The new BMW 1 Series Convertible is the latest in the line of BMW models announced in 2007 to benefit from a raft of performance and economy measures under the banner of BMW EfficientDynamics.
Brake Energy Regeneration features on all models and uses intelligent Alternator Control and an Absorbent Glass Matt battery to harness engine power that would normally have been lost during engine over-run or braking. An optimum gear shift indicator also features on all manual-gearbox cars to inform the driver of the appropriate gear for the most economical driving.
All models feature a new, clutched air conditioning pump. When not in use, the pump decouples and uses only 200 watts, or ten per cent, of the normal power needed to drive a conventional pump. In addition, other than the range-topping 135i Convertible, all models feature electronic power steering. In contrast to conventional hydraulic power steering, the 1 Series’ electronic system operates on an ‘on demand’ basis, reducing engine output normally needed to power the steering hydraulics.
All four-cylinder manual gearbox cars feature BMW’s Auto Start-Stop system as standard. In urban traffic, when the gear is deselected and the clutch pedal raised, the engine automatically cuts out, thus eliminating emissions and any fuel consumption while static. When the traffic starts moving, the clutch is depressed in order to select the gear to pull away and, immediately, the engine fires back into life.
Drivetrain and chassis - a supple yet sporting drive
All BMW 1 Series models feature a six-speed manual gearbox as standard with owners able to opt for a six-speed automatic gearbox on all models. Steering wheel-mounted paddles enabling manual shifts of the auto box are standard on 135i cars and optional on 125i models.
Finally, in common with 135i Coupé customers, purchasers of 135i Convertible models also benefit from BMW’s electronic differential lock. Promoting a sporting and involving style of driving, the electronic differential lock works when the car is accelerating hard out of corners or tight bends. In this situation, it electronically slows the spinning inside rear wheel to enhance vehicle traction and ensure that all available power is transferred to the road.