Skip advert
Advertisement

BMW i3 review – the city car perfected? - Engine and Gearbox

The BMW i3 is a genuinely impressive take on the electric city car.

Evo rating
  • Brilliant performance, great interior, stand-out looks
  • Range extender engine noisy, limited range without it

Engine and gearbox

At the heart of the BMW i3 is a bespoke electric motor tagged BMW eDrive, which its maker also refers to as hybrid synchronous in design. It was developed in-house and is also used in the BMW i8. It's mounted at the back of the car and drives the rear wheels through a single-speed transmission.

Advertisement - Article continues below

Although it revs to 11,400rpm and produces up to 168bhp, it's the torque output (184lb ft) that matters most, as it's available from the second you press the accelerator. The seamless, almost unrelenting acceleration that results from this is utterly comical at first because of the quietness that accompanies it and it becomes quite addictive.

Revealed in 2016 and updated for 2017, BMW has increased the size of the i3's battery pack. In electric-only form, capacity has leapt 50 per cent from 22kWh to 33kWh, yet the pack takes up no more space in the car's structure - an indication of the current rapid rate of progress within the industry. While the previous pack was good for around 120 miles on the European cycle (and less in real world driving) the new pack is apparently good for 195 miles.

The American EPA figures are probably more realistic indications of your actual range (and the general improvement): Previously, it rated the i3 as an 81-mile car, which has now climbed to 114 miles. Realistically you'll probably do a little better than that - 120-130 miles is achievable - but either way, a 30-odd mile gain is not to be sniffed at.

For the record, the range extender engine is a 650cc motorcycle-derived parallel twin-cylinder petrol unit mounted above the rear axle. Its 33bhp output is devoted solely to generating electricity - there is no physical connection between it and the wheels. It's fed by a miniscule nine-litre fuel tank, so-sized, we're told, to maintain the i3's boot space.

Skip advert
Advertisement
Skip advert
Advertisement

Most Popular

The £48k VW Golf GTI Edition 50 is Pagani quick around the Nürburgring
Volkswagen Golf GTI Edition 50
News

The £48k VW Golf GTI Edition 50 is Pagani quick around the Nürburgring

Volkswagen let the Mk8 Golf GTI off its leash with the hardcore, track-honed Edition 50, and its new Nürburgring lap time proves just how effective th…
7 May 2026
This unseen Slovenian tech is about to change cars forever, and I've already tried it
In-wheel motors
Features

This unseen Slovenian tech is about to change cars forever, and I've already tried it

In-wheel motors promise a revolution in vehicle dynamics, offering lightning-fast control and superior grip for performance hybrids and EVs. I put it …
6 May 2026
New Aston Martin DB12 S review – Forget Bentley, Ferrari should be worried
Aston Martin DB12 S front
Reviews

New Aston Martin DB12 S review – Forget Bentley, Ferrari should be worried

Comprehensive dynamic upgrades not only make the new Aston Martin DB12 S a better GT car, but it’s now a far better performance car, too
6 May 2026