Strength in numbers may have aided BMW's rise to a new best of fourth in 2011, but the German manufacturer ventures into 2012 knowing it needs to see greater results from its substantial investment.

After three years at the helm, Troy Corser steps aside to allow Marco Melandri to assume his place in the team, the Italian joining forces with Leon Haslam in what is arguably BMW's most accomplished line-up yet.

Having finished runner-up to Carlos Checa during his maiden WSBK season last year, Melandri comes to BMW as a man with a revived reputation and a new-found motivation for two-wheel racing after a period in the MotoGP doldrums.

Even so, the move to BMW - in the wake of Yamaha's sudden withdrawal - is perhaps more indicative of there being few well-paid alternatives available, rather than ultimate choice, and Melandri's comments pre-season about being unable to develop an affinity with the bike echo those of his unhappy tenure with Gresini Honda in 2010.

Despite this, Melandri has consistently praised the team effort, while he has been quicker in testing than his comments would have you believe, with both he and Haslam regularly bothering the top five. However, BMW will be concerned that the Italian appears to be expressing the same criticisms that have dogged the bike in its three years of WSBK racing - namely wild inconsistencies in set-up when conditions suffer even a minor change.

Though fairly level on pace, Haslam has been far more positive than his incoming team-mate and feels the S1000RR has come a long way since the Briton was on the podium at last year's season opener. A pre-season injury looks destined to set him back initially, but if BMW can give Haslam a bike to do justice to his dogged determination then a first win should be a realistic aim.

Having been a major contributory factor in BMW's run to fourth overall in 2011, the BMW Italia team returns in 2012 with a revised rider line-up, a new title sponsor and a bold livery to help differentiate it from its factory-supported counterpart.

Ayrton Badovini's impressive return to WSBK competition last season has been justly rewarded with a new deal, the Italian looking to build on the form that took him to the top ten in the overall standings. Having missed out on a podium in 2011, Badovini will immediately look to rectify that statistic, whilst maintaining the consistency that defined his campaign.

He is joined by Michel Fabrizio, who earns a stay of execution in WSBK after a fairly disastrous sole season on the Suzuki Alstare. The Italian has often proved his has the pace to compete at the highest level of WSBK racing, but fleetingly good form in 2010 and 2011 makes him something of an unknown quantity heading into 2012.

Nonetheless, despite a slow start on the S1000RR, Fabrizio has been in and around the top ten during pre-season testing, while he was also comfortably faster than Badovini at Phillip Island. It just remains to be seen which Fabrizio turns up to the opening round...

Bolstering the BMW contingent to five, Grillini Progea make a surprise return to WSBK competition in 2012 with a sole entry for Mark Aitchison. The Italian outfit was last seen in 2008 as a tail-ending Yamaha customer operation, but recent efforts to crack MotoGP with its own CRT machine suggest there is money and influence behind the team.

Turning its attentions to WSBK after failing to land a MotoGP entry, Grillini has signed Mark Aitchison for its comeback campaign, the Australian securing a second season in the top flight after a noteworthy maiden campaign on the Pedercini Kawasaki. Though expectations for the tiny team are fairly modest, Aitchison has the tenacity to be a points' contender this year.