Here Are The New, More Capable BMW i8 Coupe And Roadster

Here’s the liquid sugar with which to ice a handsome stack of news today: the new BMW i8 and its drop-top Roadster brother have been revealed in full after we first learned about them earlier this year.

Underpinning both body styles is a new, improved eDrive system with more power, a longer electric-only range and the ability to switch to the motor more of the time, but the headline act is the electrically-retractable roof panel that disappears into the Roadster’s tail.

It operates ‘very quietly’ at up to 31mph in a speedy 15 seconds. As it drops, the rear window rises by 30mm to act as a wind break and stop some of the turbulence in the cabin.

It’s about 60kg heavier than the new hard-top version, says BMW, courtesy of the roof mechanisms and a bit of extra chassis bracing. The official unladen weight stands at 1595kg. While the Coupe is a tenth faster to 62mph than the old one, at 4.4 seconds, the Roadster drops two tenths on that as it labours just that little bit harder to get its mass moving off the line.

The 2018 i8 siblings share an upgraded drivetrain with electric motor power up to 141bhp from 129bhp. The power bump comes from a significant boost in energy density, with cell capacity up from 20Ah to 34Ah.

As before, the motor powers the front wheels. Revisions to the three-cylinder turbo petrol engine powering the rears take power to 227bhp and torque to 236lb ft, and total system output is up by 15bhp at 369bhp.

Electric driving range is now up to 34 miles for the Coupe and 33 for the Roadster, and thanks to lifts in the upper speed limits the motor can sustain, you can now drive at up to 62mph on electric power in hybrid mode, up from 43mph before. That now rises to 74mph in eDrive electric mode.

Official NEDC test cycle fuel economy averages – the ones that bear no relevance to the real world – put the Coupe’s economy at 148.7 miles per gallon and the Roadster’s at 134.5mpg. A full recharge via the 3.6kW BMW i Wallbox takes under three hours.