The upcoming BMW 4-Series Convertible has been caught topless before, but now the spy images that were captured show off the details of the vehicle's roof mechanism. Just like the current 3-Series Convertible (E93), these photos officially confirm that BMW->ke178 has decided to go with the folding hard top mechanism.

The BMW 4-Series Convertible is still heavily camouflaged, hiding most of the lines, but according to some inside information, the front end will differ from the recently announced F30 3-Series sedan and will be more sculptured and sportier. In fact, rumors say that the new 4-Series->ke3834 will take most of its design elements from the 5-Series->ke317 and 6-Series->ke320, but with more squared-off headlights and larger eyebrows.

Rumors also say that the 4-Series will be offered with the latest four and six-cylinder petrol and diesel units found in the BMW lineup, including the new 245bhp 2.0-liter four-cylinder petrol engine.

The new BMW 4-Series Convertible will be launched sometime in 2013 and will go on sale as a 2014 model.

.