2015 BMW M235i Cabriolet | Review

Fatter, pricier and considerably windier than the M235i Coupe, but far more fun than you were probably expecting

Cabriolets always struggle to be taken seriously as performance cars, even if they're based on something really good. So we fully understand that the prospect of reading about a heavier, less rigid and more expensive version of the BMW M235i probably isn't making you salivate in anticipation a great driver's car.

Heavier yes, but still good fun

Yet, behind the obvious limitations that come from decapitating any structural box, there's a huge amount to like about the rag-top version of the M235i, largely because it doesn't try too hard to be something that it's not. And after recently being told that the new X6M was M's idea of the future of the performance car, the 2 Series is also welcome confirmation that BMW's go-faster division does still know how to make something with right-wheel drive, a punchy engine and a chassis that delivers an optimum balance between grunt and grip.

Who ate all the pies?
Admittedly physics aren't on the Cabrio's side. On BMW's official numbers it's a chunky 145kg fatter than the Coupe, with the extra mass of the sub-surface structural reinforcement (plus the roof and mechanism) pushing the kerbweight to a one-at-a-time-please 1,695kg. Despite that, the official 0-62mph time is only two tenths slower than that of the Coupe when fitted with the optional eight-speed automatic we tested the car with. There's no arguing that the extra mass has a noticeable effect on the Cabriolet's willingness to change direction. It's definitely not as agile as the fleet-footed Coupe, and you'll feel some understeer if you try and bung it too hard at a slower corner.

Slow-in, fast-out suits the M235i best

Next - look away, matron - rigidity. By cabriolet standards the M235i feels decently strong and stable. Anyone whose previous ragtop experience was one of the 1990s cereal boxes will find it feels like a roll cage-equipped tank by comparison. But if you try and carry an optimistic speed over a rough road surface with the roof down you do feel tremors in the structure, and see the rear-view mirror wobbling out of sequence. Find a big bump in the middle of a loaded-up corner and there's a similar sensation of an undamped force momentarily interrupting proceedings, although briefly enough its more wibble than wobble.

But...
Which brings us to the point where, if we had one, a curly-haired TV presenter would drop the 'B' word and turn the tables. Because inherent cabriolet foibles aside, the fresh-air M235i turns out to be a thoroughly enjoyable way to enjoy a cheek-tingling blast down a slippery B-road. BMW has an abundance of turbocharged straight sixes these days, and although this one can't match the output of the M4's motor, it's arguably the more charismatic unit, revving keenly beyond the 5,800rpm where peak power arrives and through to 7,000rpm, delivering some rorty harmonics while it does so.

Quite the looker given some recent BMWs

And although the M Performance 2 Series isn't a 'proper' M car within BMW's rigid hierarchy, it shares the characteristic that defines M's best offerings of having just slightly more power than grip; enough to make things interesting without getting excessively wayward. You can turn the stability control off and play the hooligan, but the M235i still feels alive with everything switched on as the tubby torque curve helps influence its cornering line. And, unlike the M4, there's definitely not a sensation-sapping superabundance of grip at road speeds, with the steering faithfully reporting fading adhesion through its electrical assistance. If anything, the cabriolet's slightly more relaxed natural pace - as dictated by its extra mass and occasional structural foible - positively encourages a sort of slow-in, fast-out technique that suits the car particularly well.

So that's a 'quite decent cabriolet' shocker, then. If you're going to do something as fundamentally daft as buy a car that's lost a major structural component, the M235i does seem a relatively painless way to do it. The Coupe is definitely still the better-driving car, but the Cabriolet certainly retains more old-fashioned M-ness than many of its supposed superiors.

BMW M235I CABRIOLET
Engine: 2,979cc, straight-six turbocharged
Transmission: Eight-speed auto, rear-wheel drive
Power (hp): 322@5,800-6,000rpm
Torque (lb ft): 332@1,300-4,500rpm
0-62mph: 5.0 sec (claimed)
Top speed: 155mph (limited)
Weight: 1,695kg
MPG: 35.8 (NEDC combined)
CO2: 184g/km
Price: £39,255 (basic RRP)