By Nauman Farooq

It might not be the perfect car for Detroit, Mi., especially in January, but still BMW held the world premiere of its second generation Z4 roadster at the 2009 North American International Auto Show.

This new roadster, which will go on sale in Canada in June of this year, finally has a folding hard-top roof, so it can compete more squarely against its main rival, the Mercedes-Benz SLK-series. The folding roof on the Z4 takes just 20 seconds to open or close.

The new Z4 also will be available from the start with three engine options, all straight-six engines. The Z4 sDrive23i produces 204hp, the sDrive30i produces 255hp, while the current range topping model, the sDrive35i produces 300hp thanks to its twin-turbo mechanics. Canada might only get the latter of the two engine options.

BMW Z4 (photo: Isaac Adams-Hands)

Choice of transmissions include the standard six-speed manual, or the new seven-speed, double-clutch, Sport Automatic.

No prices were announced at the show, but talking to a few people at BMW, they suggest it won’t be much more than the current car.

Unlike the previous model, the 2010 BMW Z4 will not be built at the Spartanburg, South Carolina plant, instead it will be built in Germany.