The 1 Series Coupe was obviously designed with a Convertible model in mind. Both cars share a virtually identical silhouette, with long bonnets, short overhangs and set-back glassy 'greenhouse' proportions. 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. 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.
This drop-top model features a fabric roof that opens or closes in 22 seconds, and at speeds of up to 25mph. The roof material 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.
Inside, BMW reckons that there's space for four occupants, though the cabin isn't as large as that of, say, convertible Audi A4s or a Saab 9-3s. Still, there's a respectable 305 litres of boot space with the roof up (260 litres with the roof down). A nice touch is a 'convertible' setting for the air conditioning when the roof is down. The high quality materials and solid construction always impress and it's this general classiness that makes it all feel special rather than any stand-out detailing. The major controls for the entertainment and ventilation systems are confined to a panel ahead of the gear lever and the rest of the stuff you need is clustered on or around the steering wheel where it's simple to access on the road.
There are four trim levels to accompany the seven engines that make up the 1 Series Convertible range though the top powerplants only come with the plusher trim levels. Buyers choose from ES, SE, Sport and M Sport. It's the M Sport package that really makes the difference to the car's appearance, and the way it drives. Buyers at this top level receive sports suspension, sports seats, an M Sport steering wheel and the M Aerodynamic package on their car.
The 1 Series has gained a reputation as a tough little thing and the Convertible is no exception. Check the usual things too - service lights illuminated, body nicks and scrapes, damaged trim, cellphone mounting holes in the dashboard and a cast-iron full BMW dealer service history. The 120d is a car that has attracted demand but some owners have 'chipped' their 118d up to and beyond the 120d's 163bhp output. This will have warranty repercussions so be careful if the 118d you're test driving is suspiciously rapid. If you are after a very rapid but economical 1 Series, this is one route to look at, and companies like Superchips can make a 135i virtually M3 V8 quick while still retaining decent reliability and economy.
It's worth being fussy (avoid dull non-metallic colours and gloomy interior trim colours) so that, when resale time comes, you'll get a lot more for your part exchange than you might expect. If you really want piece of mind, buy from a BMW dealer - but be prepared to pay the premium. The hood itself has proven largely trouble-free but it's worth giving it the once over to check for bird lime damage and any rips, scuffs or interior discolouration.
(based on a 2008 1 Series Convertible 125i - ex Vat) A clutch assembly is around £130. Front brake pads are around £40, a full exhaust about £360, an alternator around £100 and a tyre around £40. A starter motor is about £120. A headlamp is about £165.
All 1 Series Convertibles are reasonably rapid, even the entry-level 118i reaching sixty in 9.3s on the way to 130mph. The flagship 135i almost halves this acceleration figure and has to be electronically restrained at 155mph. Being rear wheel drive, the 1 Series is always going to be the default driver's choice in this segment, though we're not huge fans of the electronic power steering fitted to all variants except the flagship 135i. It operates on an 'on demand' basis, reducing engine output normally needed to power the steering hydraulics. The Active Steering option is also one we'd avoid. If you're expecting typical pin-sharp BMW dynamics, you may be a little disappointed in the way the 1 Series corners. It's certainly more of a cruiser or a point and squirt thing than a gym-toned sports car. For that you'll need to eschew the rear seats and go shopping for a Z4.
Buyers choose between either six-speed manual or automatic gearboxes. Steering wheel-mounted paddles enabling manual shifts of the auto 'box are standard on 135i cars and optional on 125i models. 135i customers get BMW's electronic differential lock which electronically slows the spinning inside rear wheel to enhance vehicle traction when the car is accelerating hard out of corners or tight bends. In this situation, it electronically slows the spinning inside rear wheel to improve traction and ensure that all available power is transferred to the road.
Should you be careless enough to be about to roll your car roof-down, a sensor will register the imminent danger and, alongside the relevant airbag deployment, two roll-over bars will extend from behind the rear seats in a fraction of a second to protect the safety cell.
The BMW 1 Series Convertible fought against two key impediments - styling and price - and has come out smelling of roses. The public's spending power only goes so far in tough times, however, and you'll find many more of the more prosaic models and significantly fewer of the big horsepower variants. The best value in the 1 Series Convertible range lies at that less well defined cusp where the two sides of the Venn diagram overlap in the form of the 125i Convertible. It's got the sweetest engine in the range and you'll value that when you're driving with the hood down. Track down a low mileage example and you'll have one of the most talented four-seat convertibles around and, dare I say, a bargain BMW to boot.