Spied! 1 Series Cabriolet

BMW hopes that the 1-Series coupe along with the introduction of a convertible variant in North America will boost the 1-Series range past the half million mark. The BMW 1-Series coupe arrives in April of 2008 followed by the 135i convertible which will be available in SE and M Sport trim levels.

Well, unlike the 3-series convertible, the 1-series gets a fabric roof rather then a more expensive and complex folding metal roof. It will of course be fully automatic – at the touch of a button on the centre console, the electro-hydraulically powered cloth and glass roof will fold into a recess behind the rear seats to leave the car clear of intrusions from A-pillar to tail light.

The folks at CarMagazine have sat in the 1-series coupe (BMW call the 135i coupe a 2+2) and rear head and leg room is fine for children but adults will find it very snug, and expect roof-up transport to be more than a little claustrophobic. That folding roof also eats into the boot space – not a particularly strong feature of the 135i to start with – so expect it to swallow a few decent sized soft bags and no more.

Expect the convertible to carry a noticeable weight penalty over the coupe – to ensure the topless 1-series still handles crisply, BMW’s engineers have added some significant chassis reinforcements to maintain chassis rigidity. That said, the twin-turbo 135i should be entertainingly brisk, hitting 60mph in just under six seconds and onto a limited 155mph top speed.

Like the coupe, the baby convertible will feature BMW’s innovative Efficient Dynamics technology which introduces regenerative braking that decouples the alternator under power but recharged the battery when braking or slowing, as well as auto-stop start on the manual transmission versions, energy-saving powered steering and on-demand water pump and climate control systems.