Piloting a Yamaha YZF-R6, Michael Sweeney followed illustrious former race winners including Freddie Frith, Bob McIntyre, Charlie Williams and TT rider liaison officer Richard "Milky" Quayle in winning the Junior Manx Grand Prix, appropriately on the day that the meeting celebrated its 90th anniversary with a past parade of former winners. The Irishman emulated his 2010 Junior MGP victory with a dramatic last lap victory after race leader James Cowton ran out of fuel on the last mile. Northern Ireland's Stephen McKnight, who finished third in both the 2011 and 2012 Junior Manx Grand Prix races, had the honor of being first away from Glencrutchery Road but by Glen Helen on the opening lap Yorkshire man James Cowton, starting fourth, had established a lead of almost a second over Ireland's Michael Sweeney who was fastest qualifier. Stephen Harper was a further two seconds back in third with McKnight and Tim Poole completing the top five. McKnight was first back to the grandstand (19:12.996/117.8049mph) but Cowton was the fastest on the opening lap with 18:55.123/119.659 which gave him an eleven second lead over second placed Michael Sweeney (19:06.369/118.485) with McKnight (19:12.996/117.804) in third and Andy Lawson (19:14.801/117.620) moving into fourth, pushing Stephen Harper (19:16.303/117.467) down to fifth. Cowton held the lead on the second lap with 19:02.121/118.926 but an efficient refuelling pit stop from Sweeney's team at the end of the second lap saw him close the gap by an estimated six seconds with 2009 Manx Grand Prix Senior Race winner Michael Russell's lap of 19:10.118/118.099 moving him into the top three. Cowton again put the hammer down and established an eighteen second gap by Glen Helen and his third lap of 19:52.315/113.920 saw him going into the last lap with a 25 second lead over Sweeney with Russell retaining third. However, in a dramatic conclusion to the race Cowton, after going through the final checkpoint at Cronk-Ny-Mona still holding a 16 second lead was reported to be out of fuel at the Nook, just a few hundred yards from the finish of the near 150-mile race. Sweeney came through to win in 1:17:20.911/117.070, with Michael Russell (1:18.01.810/116.047) moving up into the runners-up spot and 2009 Newcomer Race C runner up Andy Lawson (1:18.11.598/115.805), who moved from sixth going into the last lap, taking the final podium place.