On a day that saw the winds die down, so too did the scores, with Ian Poulter, Jamie Spence and Richard Bland all standing at 13-under-par after 36 holes.
Dane Thomas Bjorn, the winner of the BMW in 2000, is just a shot off the pace at 12-under on the strentgh of a solid second round 64.
First-round leader and four-time runner-up in this event, Bernhard Langer, got off to a shaky start but managed to get it going on the back nine and finished with a 3-under-par 69. Coupled with his 64 on Thursday, Langer is only two off the lead.
'It was definitely the hardest round I have ever played,' said Langer, who was battling food poisoning. 'If I was well down the field I wouldn't have played but once I start a round I always try to finish. It was tough but nothing is lost and two behind the leaders is not a bad situation.'
Paul Casey, the 25-year-old All-American out of Arizona State, had the day's best round, carding a flawless 63 that moved him to 9-under for the tournament. Nine birdies, six coming on a torrid back nine, and no bogeys have him in good position for the weekend.
Poulter, who has two top-10s in his last four events, followed up his Thursday 65 with a another strong 66 that included seven birdies and a lone bogey.
Spence, who had a second place finish in the TNT Open a few weeks ago, posted a remarkable 64 on Friday. Not a single bogey on the scorecard, yet eight birdies on the day got him into a share of the lead.
Bland, who has missed as many cuts as he has made this season, enjoyed another great day of shotmaking. Though he had two bogeys, eight birdies got him a 66 to join Poulter and Spence.
Defending champ John Daly carded his second straight 2-under-par 70 and just made the cut, which fell at 4-under par.
Also barely making the cut was Padraig Harrington, who like Daly had two rounds of 70. Harrington has four top-10s in his previous five starts at the BMW Open, his runner-up finish to Daly last year being one of them.
Full-field scores from BMW International Open