2017 BMW 420i Convertible review

With spring in the air, the BMW 420i Convertible could be the perfect drop-top tourer for you... as long as you don't mind a bit of compromise.

Four years ago, BMW rebranded its iconic 3 Series Convertible as a 4 Series, as part of a move to better distinguish between coupe and sedan body styles.

The fact is, old habits die hard, and some (like this tester) still find it confusing, especially when you’re trying to explain the situation to a punter at the pub, who’s talking up a keenness for a 3 Series (sorry, 4 Series) drop top.

And, as of, well, now, with the introduction of BMW's LCI models, it’s either more, or less confusing, depending on how you look at it. LCI – BMW speak for Life Cycle Intermediate, or mid-life update, to clarify matters.

Our 420i tester, is the entry-level variant in the 4 Series open-air model range, sitting under the 430i and 440i Convertibles. Of course, if you don’t desire that wind-in-the-hair feeling, there’s always the Coupe or the Grand Coupe versions to choose from.

Mind, there’s a pretty steep premium to be paid for chopping the top off your 3 Series (there I go again) sorry, 4 Series Beemer – eighteen-thousand big ones, or $87,900 plus on-roads, to be precise.

That said, it’s still thousands cheaper than the existing Audi A5 Cabriolet 2.0 TFSI quattro from $90,955 (expect a new-generation model to arrive shortly), but a couple of grand pricier than the entry Mercedes-Benz C-Class Convertible, priced from $85,900.

In some respects, the Beemer is in a class of its own, as the only folding metal hardtop against a two-pronged soft-top assault from its two German luxury counterparts.

And, it’s that three-piece folding metal hardtop, which counts most towards a level of closed-roof refinement unmatched by the Audi and the Benz. Even driving at the maximum legal speed limit, it’s easy to forget you’re driving a convertible, such is the complete lack of outside noise. It also provides far more security than a soft top, as you would expect.

The roof mechanism itself is proper mechanical theatre; separating into three distinct pieces, before coming together in seamless synchronicity and dead silence in around 22 seconds. That’s slow.

It certainly looks the part, too, like a proper BMW two-door coupe should – low-slung, with a wide stance.

There are new bi-LED headlamps, as well as front LED fog lights across the entire 4 Series range. They’re complemented by a revised front apron, highlighting that stance further.

Around back, there’s more LED lighting and another new bumper design that gives the 420i a decidedly planted look that’s capped off by a very tasty multi-spoke wheel design.

Inside, there’s nothing entry-level about the 420i. The Dakota leather seats are simply sublime in their ability to provide comfort and support, offering the perfect balance between sports and luxury, but still wide enough for larger frames. Even the steering wheel gets a new type of leather wrap – using ‘Nora’ leather for a softer, more tactile feel in the hands.

As nice a place as the 420i Convertible is, you’ll need to think very carefully about weekend trips away, given the limited space available – that’s rear-seat legroom and luggage space. Neither are strong selling points. Drop the roof, and there’s room in the boot for handbags only, but I suppose you can always use the second-row seating. Close the roof and that space expands to 370 litres – enough for the weekly food shop... just.

Despite various updates along the way, it’s not the most contemporary of dash boards, particularly with its traditional analogue instrument display. However, all the major touch points are thickly padded and the materials of a premium quality.

There’s no shortage of kit, either, despite its base-level status in the model range. The latest iDrive6 interface provides both touchscreen access, as well as via the rotary controller. It’s a neat system that now shows a variety of app-style tile displays that can be opened via touch.

The Luxury Line trim is standard on the 420i Convertible, meaning, there’s a long list of creature comforts including exterior features like mirrors with anti-dazzle, front and rear parking sensors with rear-view camera, head-up display, electric seats with memory, DAB digital radio, and surround view.

Safety gear includes driving assistant (combines lane departure warning and approach and pedestrian warning with city brake activation), speed limit info and Emergency call and Teleservices (which advices when services are due and passes info about the state of the car directly to the dealer).

Along with the usual suite of front and rear airbags, there’s also roll protection in the form of protective steel roll bars which deploy if the sensors detect a rollover is imminent.

It’s not all roses, though. The convertible tips the scales at 1660kg – nearly 200kg more than the 420i Coupe, and there are strong indications this has a decidedly adverse effect on ride, handling and performance.

Let’s start with the latter. Whereas the coupe can scoot from 0-100km/h in a respectable 7.3 seconds, the drop-top is almost a full second slower to the line (8.2). And it feels that way, too. Almost sluggish, even under full steam.

It’s a tad peppier if you select the sportier drivetrain modes, which dial up throttle response a notch or two, though don’t expect it to ever get your heart racing. It simply doesn’t like to be hurried, instead, preferring to be treated more like a soft-pedalling boulevard cruiser.

At low revs, the four-pot is actually smooth and relatively refined. Press on, though, and there’s more noise, but again, it’s not a sporty exhaust note, more like a couple of Singer sewing machines working overtime on the double-stitch, rather than a nice four-pot snarl.

At least, that’s the effect with the roof closed. For reasons we can’t fathom, there’s nothing pleasant piped into the cabin, but open the roof, and you’ll be rewarded with something far more pleasing to the ear.

Even at speed, there’s very little turbulence inside the cabin. In fact, it's negligible, especially with the windows up. And that’s without the manually-mounted wind deflector in place.

Perhaps, we’re being a bit too harsh, but this is a BMW two-door, and we’ve come to expect more from the brand when it comes to good ol' fashion go, even those with 2.0-litre displacements.

Mind, it’s no slower than the C200 Convertible that makes the same power, but even less torque (300Nm), though it’s a second slower than the equivalent A5 Cabriolet, which benefits from more power and torque (165kW/350Nm) but carries considerably more weight thanks to its quattro all-wheel drive layout (1735kg Vs 1660kg).

That said, there is a fix, provided you’re prepared stump up another 10-grand for the 430i, which also gets a four-cylinder motor, but uprated to a more enthusiastic 180kW and 350Nm, and good for a 6.4 second sprint from standstill to 100km/h.

Handling-wise, the 420i Convertible is pretty good. By that, I mean, it turns in sharply, the steering is meaty, and the car feels quite taut and responsive in that regard. That’s down to stiffer springs and improved damper settings with the standard adaptive suspension, which effectively reduces body roll and allows for a more enjoyable time behind the wheel.

And, being rear-wheel drive, it’s nicely balanced and can be a bit of fun through chicanes – with the roof up.

Sadly, there’s still a degree of body wobble – which only worsens with the roof down. In fact, you can feel the whole car vibrate, even over mild road blemishes. While we might expect more from a BMW, it is, however, better than its rivals in this regard.

Ride comfort, though, is very well sorted, despite riding on standard-fit 19-inch light alloy wheels, wearing low-profile (255/35s) Pirellis on all four corners.

Larger bumps and even broken road with sharp edges are completely absorbed, so the cabin remains a comfortable place to be. We deliberately sought out the roughest patches in an attempt to upset the suspension, but still, the 420i was able to successfully deal with all manner of road surfaces.

Even as the entry-level convertible, the 420i seems like an expensive proposition, especially when you factor in the rather lacklustre straight-line performance.

On the other hand, it’s a few thousand cheaper than the Audi equivalent, and is the only folding metal hardtop amongst its German rivals. It also comes loaded with luxury kit and is arguably the better looking of the bunch.

Of course, if you don’t need the space, but you’re after more performance, the M240i from $83,900 makes a whole lot of sense, armed with a 3.0-litre six making 250kW and 500Nm.

Click on the Gallery tab for more images by Sam Venn.

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