The existing 118i petrol and 118d diesel both carry over unchanged, as does their pricing starting from $36,900 and $40,300 respectively.
Changes start with the 120i, which adopts a substantially revised 2.0 litre turbocharged four-cylinder petrol engine, boosted to 135kW of power and 270Nm of torque (up 5kW and 20Nm).
The 120i also comes standard with BMW’s Sport Line package, equipping it with a rear-view camera, dual-zone climate control, 17-inch alloy wheels, ConnectedDrive, and extended smartphone connectivity.
The new engine is also slightly quicker than the one it replaces, with a 0-100 km/h sprint of 7.1 seconds (0.1 seconds faster) while fuel consumption is rated at 5.8 l/100km.
Moving up to the 125i brings a standard M Sport Package, and M Sport brakes, while 18-inch alloy wheels, front and rear park sensors, Alcantara and cloth upholstery, anti-dazzle mirrors, and LED foglights make their way onto the standard features list.
In the case of the 125i, a new high-output 2.0 litre turbocharged four-cylinder engine delivers 165kW and 310Nm, up 5kW while torque stays the same; 0-100 km/h drops 0.1 seconds to 6.1 seconds, and fuel consumption drops 0.6 litres to 5.9 l/100km.
At the top of the range is BMW's new M140i nameplate, stepping in for the previous M135i, and powered by a 250kW and 500Nm twin-scroll turbocharged 3.0 litre straight-six engine.
The M140i can bolt to 100km/h in 4.6 seconds, down from 4.9 for the M135i and fuel consumption improves from 7.5 l/100km to 7.1 l/100km.
Standard features include DAB+ digital radio, Professional Navigation, adaptive LED headlights, and Adaptive M suspension.
All new 1 Series variants come standard with an eight-speed automatic transmission, with the no-cost option of a six-speed manual available. The updated range will be available in Australia from the fourth quarter of 2016.
NOTE: Prices exclude on-road costs.
Update: An earlier version of this article showed the fuel consumption of the 120i as 5.5 l/100km. That figure, supplied by BMW, is for European specification vehicles on 16-inch wheels, Australian vehicles differ in their specification, including 17-inch wheels and the fuel consumption figure has been updated to reflect this.
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