BMW 135i Cabriolet (2008)

Published: 20 August 2007

A 1-series convertible – that’s niche marketing for you…

Yes, BMW is leaving no market sector unoccupied with its 1-series. Due to be unveiled at next year’s Detroit motorshow in January – BMW is hoping that 1-series coupe and convertible take-up in America will boost 1-series past the half million mark. It arrives here in April with the range spearheaded by the flagship 135i convertible, available in BMW’s two familiar trim levels – SE and M Sport. We anticipate the topdog M Sport to wear an anticipated £34,000 price tag. Expect it be followed by the 125i powered by BMW’s 218bhp 2.5-litre six-cylinder petrol engine as well as the 204bhp twin-turbo 123d diesel by the end of the year.

Tell me about the roof

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. We’ve sat in the 1-seies coupe (BMW calls 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.

Anything else I need to know?

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.

By Ben Whitworth

Contributing editor, sartorial over-achiever, HANS device shirt collars