BMW i8 Roadster review: This is a clean, green, seriously mean sports car6 min read . Updated: 12 May 2018, 09:25 AM IST BMW’s roadster version of the stunning i8 coupé is a step up in almost every area. This is one car that gives you the best of both worlds.
BMW's i8 was the world's first carbonfibre-made, plug-in hybrid-powered sportscar and it took the sportscar game a huge step ahead, at least as far as technology was concerned. The i8 used only a three-cylinder turbo engine with torque from a big electric motor. Now, over five years after the hard-top, comes the i8 Roadster - a car that allows you to enjoy open-top motoring, as well as clean, green sportscar fun, all rolled into one stunning multi-layered, multi-surfaced mid-engine sportscar.
While the basic shape of the car remains the same, with its stunning proportions and overlapping sections done in contrast colours, the roadster gets new 'comets' behind the headrests, a new 'engine cover' and reconfigured doors. Also new, of course, is the part-fabric roof that folds into a panel behind the headrests. The operation of the roof is silent since actuation is totally electric, with no whining hydraulic motors present. And what's nice is that you can go from fully open to fully closed in just 15sec. And you can even do it even if you are travelling at 50kph. Neat.
BMW has also worked hard to make sure there is no buffeting or ballooning of the soft-top at speed. To this end, the canvas roof has a band of carbon-fibre built into it at the point at which it meets the windscreen. This reduces buffeting at speed and makes for a solid fit with the modified windscreen top. The company has also managed to keep the butterfly doors of the coupé and it has done this by using a part-frameless design for the doors. The car still retains the front quarter-glass and other bits, and the massive blindspot around the thick A-pillar also remains. It's something you need to be wary of.
Combined power is now up to a maximum of 374hp, and here on the roadster 0-100kph takes just 4.6sec; incredible for just a three-cylinder turbo engine with some electrical assist. While maximum power on the 231hp three-cylinder turbo engine appears to be the same on paper, the power and torque curve are clearly more muscular, with the engine making a lot more grunt in the mid-range. Also increased substantially is the capacity of the battery. The new battery is an 11.6 KWh unit, as against the 7.1 on the earlier i8 coupé, so electric-only range is up to 50km, and the electric motor now puts out 12hp more.
The new higher capacity battery uses more potent cells but is the same size outwardly and is installed in the same enclosure as before, between the seats. Also similar is the basic structure of the car. The carbon-fibre tub had been reinforced, of course, to compensate for the roof being lopped off. This has been done by using many strips of carbon fibre installed in circular sections throughout the tub of the car. BMW, however, says that the carbon-fibre structure was already so strong, too much reinforcement wasn't needed. Most of the 60kg increase in weight comes from the folding-roof mechanism and additional arms (known internally as 'Z bars') that have been included in the rear suspension.
It looks very similar to the earlier i8 coupé. The dash feels extremely modern and light, surrounded as you are by swathes of carbon-fibre. The doors feel featherlight when you pull them shut, and, overall, you get an impression of being sat in something very futuristic.
Still, there are some key differences. Look behind and there are no rear seats, making this a two-seater, against the coupe's 2+2 setup. There's additional stowage behind the front seats now, and you can keep a couple of soft bags there, and BMW has even created individual fold-out sections or separators that help keep luggage in place. The seats are new and much more comfortable, despite being even more supportive in corners, and they are powered seats with memory, to make this car a bit more luxurious. And BMW's iDrive system finally gets a touchscreen.
On the move, with the roof closed, there isn't much of a difference between the roadster and a regular i8. This is particularly true at low and medium speeds, where almost no outside sounds creep into the cabin, the i8 Roadster behaving like a car with a hard-top. There is a bit more of a roar at higher speeds, but what must help here is that BMW has used noise cancellation technology to keep the cabin silent. And it seems to work. Getting in and out of the car is difficult. Contortions are required to get your leg into the footwell, your back needs to bend before you can slide onto the seat, and then even getting your second leg in is difficult. It makes you question the practicality of those butterfly doors. But they do look stunning.
With the roof open and driven by electric power alone, the i8 Roaster seems to just waft through the green and leafy country roads on our route; very apt. It responds to a tap on the throttle almost immediately because of the electric drive, and though max electric power is 143hp, there's a strong 250Nm of torque delivered from 0rpm. So, the i8 feels surprisingly sprightly when you tap the throttle, and progress on city streets is near effortless.
Place the new i8 Roadster in Comfort mode and the three-cylinder turbo engine augments the electric drive systems, and, as a result, the i8 feels even more energetic. Knock the gear lever sideways, put it in 'Sport', however, and the i8 transforms from a fast car into something that feels lightning quick. Now power from the electric motor and the turbo engine seem to fall over each other in a rush to get out, and this simultaneous explosion of toque results in acceleration that's just explosive. Wow, this sure feels like 0-100 in 4.6sec.
What rounds off the driving experience nicely is the fact that the car feels lithe, light on its feet, and extremely comfortable being hurled around corners. There's a directness and weight to the steering that feels perfect. The retuned i8 now turns into corners with plenty of confidence and what's reassuring is that it has so much poise, you tend to keep pushing it harder and harder. Even the brakes are super, with no hint of regeneration being carried out.
The ride too is much improved over that of the earlier i8. Sure, there's still a hint of stiffness and it does thud occasionally through large holes, but there's also plenty of suppleness. And that just makes the i8 Roadster so much more usable.
With this car, what you get is the best of both worlds. On one hand, the plug-in hybrid has an all-electric range of 50km, so you can cruise around in electric mode only with the top down and truly enjoy the sights and sounds convertible motoring has to offer. It also has a more comfortable suspension, additional performance and is a big step up when it comes to driving dynamics. The i8 Roadster will be expensive when launched at an expected price of ₹2.8 crore, towards the middle of the year, but if you want an open-top sportscar that's clean, green and seriously mean, this is the one for you. Competition? What competition? The i8 still is in a class of one.