After months of speculation, BMW finally revealed the i8 Roadster production version recently at the 2017 LA Motor Show. In the UK, the two-seater is expected to enter the market towards the beginning of 2018 next to the face-lifted two-plus-two i8 Coupe. Reaching nearly 370bhp, this petrol-electric hybrid has been a long wait after the concept was originally shown at the Beijing Motor Show in 2012. Last year, we saw the updated concept at the Consumer Electronics Show but it’s good to finally have the production model on show.
After at least five years of development, this will become the first ‘i’ model to offer a new open-top roof structure. Behind the cabin, two buttresses hold the roof whenever the magic button is pushed and it remains out of the way until needed once again. Consisting of integrated header rails and the main fabric panel, the roof can open in around fifteen seconds even when traveling up to 30mph.
As you may have seen, the windscreen has been adjusted in order to fit the new roof so users will benefit from a strengthened frame along with stronger quarter windows. Elsewhere, the rear window has also seen changes since it can be open or closed regardless of the roof’s position; it also doubles as a wind deflector for this very reason.
If we look to the i8 Coupe, you’ll quickly see the changes in design and this is highlighted in the lack of rear side windows. Instead, black panels are used with aluminum-style trims which adds to the style alongside the word ‘Roadster’. After removing the lift-back tailgate, BMW has also introduced a new engine cover.
Moving away from the aesthetics, weight has been an important concern for BMW and the Roadster comes in around 60kg heavier than the Coupe at just under 1,600kg; they say the aluminum and carbon-fiber-reinforced plastic add to the structural integrity which allows the weight to be kept low. With just two seats now, the i8 Roadster offers space of 92 liters in three different cubby holes within the rear bulkhead.
To facilitate the newest version of the iDrive System, BMW has adjusted the dashboard in both models and the seats have also been designed especially. As mentioned at the beginning, the two models will now utilize a petrol-electric (plug-in) hybrid driveline which can already be found within the existing Coupe; BMW has called it the LifeDrive architecture. With a mid-mounted turbocharged 1.5-liter three-cylinder petrol engine, this combines with the electric motor to provide flexibility. Depending on the set up, the design will either offer front-wheel or four-wheel drive.
Using a six-speed automatic gearbox, the lb-ft of torque is similar to previous units but the electric motor now has additional speed. Combined, the model should reach 369bhp and torque loading of 420lb-ft (this actually changes, however, depending on the traction and grip on the road). In the central control system, the driver will have access to five different driving modes including eco (hybrid), eco (electric), comfort (electric), comfort (hybrid), and sport.
So far, BMW believes 4.6 seconds to be an accurate estimate for the 0-62mph speed test for the Roadster and 4.4 seconds for the Coupe. With the new lithium-ion battery, the cell capacity has been boosted to 34Ah (from 20Ah) and both models should offer a range of around 34 miles. If you’re a fan of electric cars, you’ll also be aware of the new 360-degree electric charging system. With 7.2kW charging, it takes just three hours to reach 80% charge which is a large improvement in efficiency.