For a supermini to be successful, it needs to perform a seemingly impossible task: it must appear larger on the inside than it does from the outside.

Of course, the laws of physics might have a thing or two to say about that, but that didn’t stop Alec Issigonis from achieving this goal with the original Mini, from which one could argue the entire market segment now takes its name.

Rather encouragingly, we’ve seen with the Optima that Kia has a history of performing minor packaging miracles, so it was with raised expectations that the new Rio arrived for a week’s testing, accompanied by a press pack that described Kia’s global best-seller as a ‘big little car.’

Well, they’re right.

At 6ft4, I’m well practised at performing the ritual of cranking the driver’s seat as far back as it will go before climbing aboard, but in the new Rio finding a comfortable position actually involved bringing the seat forward a notch or two.  That almost never happens.

It’s not just a generosity of legroom that’s on offer, here – there’s gallons of headroom, good shoulder room, and an overall feeling of width to the cabin that makes the Rio feel larger than it really is.

the Rio feels larger than it really is

Admittedly with my lanky frame in the driver’s spot, anyone sat behind gets something of a bum deal, but with a normal human pilot three adults can travel in the back without too much trouble.

There’s good oddment storage, too, with plenty of spaces to dump a phone, sunglasses, water bottles, etc.

Kia’s cabin quality continues to impress, most notably with a chunky steering wheel and well-oiled column stalks and switchgear, although whoever designed the display for the climate control needs to go stand in the naughty corner for a while; its red lettering is incredibly difficult to read in even the best lighting conditions, but on a sunny day and through sunglasses, the read-out is completely invisible.

Which is baffling because the main instruments are delightfully clear and easy to read, while the touch-screen infotainment system offers a simple and intuitive interface design, complete with both Android Auto and Apple CarPlay.

As well as decent cabin space, Kia’s engineers managed to increase boot capacity by 37 litres, but went further by creating a lower and wider tailgate opening to make loading easier.  They even found time to squeeze another two litres of capacity into the fuel tank.

From which sips either a 1.4-litre diesel in 76hp and 89hp guises, plus 83hp 1.25-litre and 98hp 1.4-litre petrol units.

There’s also a new 1.0-litre T-GDi three-cylinder unit – despite the ‘D’ it’s actually petrol, standing instead for Turbocharged Gasoline Direct Injection – and it’s available in 99hp and 118hp forms, the latter reserved for top-spec ‘First Edition’ models, although both have identical 171Nm torque peaks.

We spent a week with the 99hp 1.0-litre, and despite being short of a piston we found it to be a willing performer.

despite being short of a piston, we found the 3-cylinder to be a willing performer

Most impressive was its resistance to stalling, with even the clumsiest of clutch engagements failing to cause embarrassment.  That’s perhaps largely because peak torque arrives from just 1,500rpm, although out on the open road it’s still an engine that needs to get its legs under it before it delivers its best.  Do that, and you’ll be treated to a pleasingly off-beat three-cylinder buzz, although for the most part it’s a remarkably subdued little powerplant.

While the 118hp incarnation is matched to a six-speed manual, the less powerful version makes do with just five.  As it happens, its ratios have been intelligently selected to match the engine’s power delivery, and as it also offers a deliciously light shift-action it’s no hardship to rifle your way through the ‘box in the interests of making good progress.

Road noise over coarse surfaces does let the side down a little, however, although we will say wind noise isolation is impressive.

On a twistier piece of tarmac the little Rio handles itself well, cornering flatter than you might imagine for a car in this class, although the steering – usefully light at parking speeds – offers little in the way of feedback.

But then buyers of 1.0-litre superminis are more likely to be interested in cost of ownership than concerns about chassis responses, and after a week’s testing we notched up an average of just under 44mpg.  Plus all of this is covered by Kia’s seven-year 100,000-mile warranty.

True, prices have increased over the old model, with each grade roughly £1,000 more than before, and there’s no three-door model any more – Kia say it wasn’t a big seller.

With global sales of the old model reaching nearly 475,000 units a year, it’s unlikely that’s something we’ll be able to say about the new Rio.

Tester’s Notes

  • Characteristically clear instruments, but climate display almost invisible except at night
  • Quality feel from switchgear and steering wheel
  • Generous interior space for front seat passengers; Good oddment storage
  • Rides well, corners flatly.  Road noise can be intrusive over coarse surfaces and cat’s eyes
  • Plenty of pull-away torque from 3-cylinder engine
  • Gearing well judged, doesn’t require a sixth ratio; slick shift-action
  • Engine noise kept well in check, appealing 3-cyl warble really only audible at higher revs
  • 44mpg on test
Entry-level Price £12,135 Price as tested £16,930
Engine 998cc 3-cyl petrol Transmission 5-speed manual
Power 99hp @ 4,500rpm Torque 171Nm @ 1,500-4,000rpm
0-62 10.3 secs Top speed 115 mph
Economy 62.8 mpg CO2 102 g/km
Dimensions 4065 x 1725 x 1445 (LxWxH) Kerb Weight 1228 kg