Hmmm. What BMW made people feel in its early days was not “joyous”, but “frightened” as those Munich-engined warplanes swooped out of the sky, machineguns blazing.

It’s much the same story with the Beethoven/Schiller Ode to Joy. It isn’t. It’s a stirring piece of music, for sure, but even before the European Union got hold of it, it was never quite as happy-making as, say, the Carpenters’ Please Mr Postman.

Joy’s not really a German thing, I suppose. We do joy. The Americans do joy. The Italians do joy, even though they never laugh. Germans, though? They’re rather better at precision and accuracy and following orders. Which is why I can’t quite understand what went wrong with the new convertible version of the 135i.

It is featured right at the start of the “joy” commercial. The driver is an old man in a hat who is smiling enormously, presumably because he’s just caught a glimpse in the rear-view mirror of his comedy moustache. Certainly, it’s not because of the car.

I like the hard-top 135 very much. In a road test on these pages, I said it harked back to the big engine/small car philosophy that crystalised the BMW range back in the early Eighties. I even gave it five stars, and so I was looking forward to driving its convertible sister.

The 3-litre engine’s unchanged and it’s still great. You have one little turbo that gets you going and then another enormous turbo that kicks in if you really need some clout to overtake. The result is better economy allied to a seamless, relentless, muscular stream of power that’s never exciting or zingy, but always there, ready to arm wrestle its way into your consciousness.

However, the convertible is 254lb heavier than the coupé and that iron lard makes its presence felt every time you put your foot down. This car is as zesty as Stonehenge.

Of course, you’d imagine that with 254lb of strengthening material, it would at least be rigid and strong. But no. All the time the steering wheel is wobbling and vibrating, and sometimes you can actually feel the flex that is sort of inevitable when the front and the back are joined together by only the floor and a bit of Millets canvas.

I don’t doubt that, in extremis, the 135 will handle nicely. And we know it’s quite fast. But there is no excitement here. Not even a crumb of joy.

As a practical proposition, it’s not much cop either. The boot is tiny and the rear seats are suitable only for people with no legs. I should also mention that with the electric roof up, you cannot see what’s coming at oblique road junctions and that getting it down takes a yawning 22sec.

In theory, this car should be very good; a modern-day incarnation of the old 2002 or the 323i. I like the manually adjustable seats and the lack of styling. I like the fact the roof is canvas rather than metal. It feels like the sort of car in which the need for driving pleasure has been put above the need for gimmicks and gadgets. But what results is neither an ode to joy, nor a very good car.

BMW 135i M Sport convertible

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