Skip advert
Advertisement

New BMW i8 Roadster 2018 review

The hi-tech BMW i8 plug-in hybrid loses its roof, but has it gained extra appeal over the Coupe?

Find your BMW i8
Compare deals from trusted partners on this car and previous models.
Or are you looking to sell your car?
Value my car
Fast, no-nonsense car selling
Value my car

As spectacular to look at as ever, the new-for-2018 BMW i8 still feels every bit the hi-tech sports car, too. Losing its roof has enhanced the experience; the open-top adds to the thrills, making it well worth the extra cash over the Coupe. There are alternatives for similar money that are more exciting to drive, but in lots of ways, the i8 makes them feel old-fashioned.

Advertisement - Article continues below

BMW has revised its i8 for 2018, introducing an all-new open-top version. The i8 Roadster sits alongside a revised Coupe, losing the latter’s solid roof and back seats, while gaining 60kg and an additional £12,000 on the price. But does that add up to a worthy trade?

The extra mass is a result of structural work to the carbon-fibre passenger cell. There are a few extra layers of carbon fibre around the windscreen and extra panels provide a stronger location for the Roadster’s rear suspension.

Best convertible cars

Elsewhere, the Roadster’s DSC system and adaptive dampers get unique tuning. Overall the i8 soft-top tips the scales at 1,595kg; hardly portly for a hybrid sports car with show-stopping gullwing doors.

The new roof is almost as spectacular as it delicately glides out of sight in a matter of seconds. It’s stored vertically where the back seats would be in the Coupe, and frees up an extra 92 litres of storage.

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

Used - available now

iX

2022 BMW

iX

8,551 milesAutomaticElectric

Cash £35,354
View iX
e-tron Sportback

2023 Audi

e-tron Sportback

53,944 milesAutomaticElectric

Cash £24,933
View e-tron Sportback
Yaris

2024 Toyota

Yaris

42,616 milesAutomaticPetrol1.5L

Cash £14,343
View Yaris
XCeed

2024 Kia

XCeed

24,858 milesManualPetrol1.5L

Cash £15,569
View XCeed

As with the Coupe, the Roadster gains BMW’s latest electric technology. Battery capacity has increased, which bumps power up from 129bhp to 141bhp and battery-only range from 22 to 33 miles.

There was always a pleasing novelty to cruising around in silence in any i8, and that’s amplified (so to speak) without a roof. Call for more speed, and the petrol engine jumps in. It’s the same 1.5-litre three-cylinder as before, but with an added particulate filter to reduce exhaust emissions.

Advertisement - Article continues below

Performance might not be supercar-quick on paper, but in the real world it feels rapid. The instant shove of electric torque helps the i8 leap forward like a car half its weight, and the engine is more than willing to pull strongly to the red line, albeit without the thunderous drama of a Mercedes-AMG GT Roadster.

Nor can the chassis match that car for thrills. With the electric motor driving the front wheels and the petrol engine the rears, you have to be completely brutal with the throttle to even induce the slightest slip from the back end. Otherwise, the i8’s natural tendency is towards understeer. You’ll be hard-pressed to notice the Roadster’s extra weight compared with the Coupe, though.

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

• The best sports cars of 2018

However, the same can’t be said for refinement. While closed-top driving is perfectly fine, with the roof down, those buttresses generate a fair amount of wind noise at anything above 65mph. It’s a shame, because otherwise the i8 would be a fantastic long-distance cruiser.

But what about fuel returns? The 33-mile electric-only range is achievable in the real world, but you’ll need to make sure that the battery is well topped up for that to translate into hybrid-like mpg figures. Drive it hard, or simply treat it like any other performance car, and you’ll be unlikely to get much above 30mpg. Still good for a sports car, but some way short of the claimed 141.2mpg.

This test car comes with more than £10,000-worth of options, and we wouldn’t really bother with any of them. Half of that cash is taken up by laser lights – a feature that’s only really a benefit at full beam; another £2,750 pays for orange upholstery and £1,600 covers the carbon-fibre interior trim.

That material sits in an interior that is starting to look a little past its best. It’s not bad, but while the spectacular body still resembles a concept from 2030, the inside can’t match its theatre any more.

Skip advert
Advertisement
Chief reviewer

Alex joined Auto Express as staff writer in early 2018, helping out with news, drives, features, and the occasional sports report. His current role of Chief reviewer sees him head up our road test team, which gives readers the full lowdown on our comparison tests.

New & used car deals

Dacia Spring

Dacia Spring

RRP £14,995Avg. savings £2,765 off RRP*Used from £10,000
Volkswagen Polo

Volkswagen Polo

RRP £15,270Avg. savings £1,925 off RRP*Used from £6,590
Renault Clio

Renault Clio

RRP £16,175Avg. savings £2,431 off RRP*Used from £6,595
Volkswagen Tiguan

Volkswagen Tiguan

RRP £38,050Avg. savings £3,360 off RRP*Used from £29,823
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

Jaguar Land Rover recalls 170,000 SUVs with UK cars experiencing similar problems
Land Rover Defender 110 Trophy Edition - front action

Jaguar Land Rover recalls 170,000 SUVs with UK cars experiencing similar problems

JLR has recalled models from across the Jaguar, Land Rover and Range Rover ranges over a faulty DC-DC converter module
News
30 Apr 2026
Car Deal of the Day: Omoda 7 offers space and super-low running costs for just £229 a month
Omoda 7 - front tracking

Car Deal of the Day: Omoda 7 offers space and super-low running costs for just £229 a month

The Omoda 7 is the latest Chinese SUV to arrive in Britain. It’s our Deal of the Day for 30 April.
News
30 Apr 2026
New Peugeot 208: electric supermini to channel iconic 205
New Peugeot 208 exclusive image - front

New Peugeot 208: electric supermini to channel iconic 205

The new Peugeot 208 will be previewed at the 2026 Paris Motor Show, but our exclusive images show how it could look
News
1 May 2026