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

Can BMW’s £50k sports coupe beat the Audi RS3? – car pictures of the week
Audi RS3 and BMW M240
News

Can BMW’s £50k sports coupe beat the Audi RS3? – car pictures of the week

In the current issue of evo, we test BMW’s updated M240 against the Audi RS3 – these are our favourite shots
18 Jul 2026
Mercedes-Benz A-class review – the Audi A3-rivalling hatchback Mercedes can’t afford to kill
Mercedes-Benz A-class front
In-depth reviews

Mercedes-Benz A-class review – the Audi A3-rivalling hatchback Mercedes can’t afford to kill

The current A-class is now almost a decade old. Happily, it still looks and feels relatively fresh
16 Jul 2026
This is the next BMW M3 before you’re supposed to see it, and it’s not electric
2028 BMW M3 petrol spies
News

This is the next BMW M3 before you’re supposed to see it, and it’s not electric

The highly anticipated launch of the Neue Klasse BMW M3 is getting closer, and now we’ve had our first look at the petrol-powered model undergoing tes…
17 Jul 2026