The Forfour Electric Drive’s powertrain gives it relatively strong and typically smooth performance where it really needs it.
It doesn’t match bigger and more expensive battery cars for outright torque or easy acceleration, and among the rivals offering markedly more instant pulling power is the e-Up.
Still, there is a decent turn of speed here, more than you’ll find in some city cars, up to the kind of pace that you’d imagine city cars will see only rarely.
The 13.2sec the Forfour needs to hit 60mph from rest is almost 4.5sec less than was required by the related 1.0-litre Twingo we tested, and the electric Smart beats its petrol-powered cousin by a similar margin from 30-70mph.
The 1.0-litre Viva is narrowly quicker than the Smart over both measures, though. That’s hardly a surprise, because, from the Forfour’s driver’s seat and beyond about 50mph at least, you wouldn’t say the car felt swift.
When straining along a motorway slip road or pulling out to overtake above 60mph, the Smart is quite plainly slow and feels almost vulnerably so at times.
Up to 40mph, though, it is quite punchy – quicker than that petrol-powered 1.0 Viva – and feels fleet and responsive enough to outsprint most city traffic.
Coasting and regenerative braking could be handled better. The Forfour features a radar-guided battery energy regeneration system. In normal operating mode, it should coast when you lift off the accelerator pedal and the road ahead of you is clear, but when there’s traffic ahead, it should automatically regenerate down to the prevailing speed of the car in front.
In practice, the system doesn’t work brilliantly and can make the Smart’s off-throttle behaviour unpredictable. Select Eco mode and the radar trickery is disabled, allegedly giving you maximum battery regeneration as soon as you lift off but also leaving the brake pedal inconsistent in its feel and its progressiveness.
All things considered, the business of interacting with an electric powertrain, and of getting the best efficiency out of it, isn’t made as easy in this car as it is in other EVs.