Sony and the developers of DriveClub have confirmed that Drive Club Bikes is real. The game will be available for download from PSN immediately after the announcement at Paris Gaming week as an addition or as a standalone game.
It was earlier leaked when a member of NeoGAF, a thumbnail for the title was posted on the PlayStation Europe Flickraccount earlier this week.
Source: NeoGAF, PlayStation Europe Flickr, Paris Games Week 2015
