The Northern Ireland racer had earlier reduced a 20-second deficit to race leader Russ Mountford to only five seconds before Mountford’s Suzuki blew its engine on the third lap.Conditions were described as good around the course although Clerk of the Course Phil Taubman advised competitors that lack of adhesion flags would be displayed at Laurel Bank, Black Dub, Quarry Bends and Ramsey HairpinIsle of Man based rider Johnny Barton, riding the Suzuki GSXR that he put on the podium last year, carried the number 1 plate and was first away on Glencrutchery Road, but was reported as having retired shortly after the start at Crosby Crossroads, conveniently close to his house.Michael Dunlop appeared to be struggling to fire his machine on the start-line but appeared to get away without any obvious problems from his start position of number 7 and was second at Glen Helen, five seconds behind race leader Russ Mountford with Mick Godfrey on a Kawasaki in third. Dan Kneen and Alan Oversby made up the top five.That remained the top five at Ramsey although Kneen moved in front of Godfrey. Mountford built on his lead over the mountain section, with Dunlop reported to have pulled over to make adjustments, and Mountford extended his lead to 24 seconds ahead of Michael Dunlop with 19:37.69 (115.334mph) to Dunlop’s 112.993mph (20:02.10) but with Kneen quitting the race in pit lane with reported brake problems, Godfrey moved back into third place.Dunlop closed the gap to sixteen seconds at the end of the second lap, posting the quickest lap of the race with 19:35.39 (115.560mph) and with a slick pit stop the difference between the front two was down to five seconds by Glen Helen on the third lap with Mick Godfrey consolidating third place.However, with the race set for a thrilling finish reports came through that Russ Mountford was a retirement at Sulby Bridge, with the Suzuki reported to have blown its engine leaving Dunlop with a lead of almost two minutes from Godfrey by Ramsey with Alan Oversby on a 750cc Suzuki in third.With rain also reported at Glen Helen on the fourth lap, Dunlop eased off to take the win with a time of 1:20.27.51 (112.545mph) from Mick Godfrey 1:23.10.37 (108.872 mph) with Oversby (1:24.37.70 – 107mph) consolidating the final podium place.Chris Palmer was first away on his 250cc Yamaha in the Junior Post Classic race that ran concurrently with the Classic Superbikes. He led at Glen Helen and was clocked at 5 minutes 8.75 seconds – a time that would have placed him third in the Classic Superbike class at the end of the first sector.Palmer built a commanding lead of over 27 seconds ahead of Roy Richardson by the Bungalow and posted a new lap record of 20:12.59 (112.015mph), the first lap record of the meeting and an opening lap time that would have put him in third place in the Classic Superbike class. It gave him a lead of over 28 seconds ahead of second placed Roy Richardson with Phil McGurk a further 25 seconds back in third.Palmer again broke his lap record on the second lap with 20:05.82 (112.644mph) but reports came through shortly after that he was a retirement at Appledene on the third lap, leaving Richardson to take the lead from McGurk with Brian Mateer holding third.That remained the final result with Richardson 1:24.41.55/106.919mph taking the Post Classic MGP title by 1 minute 29.94 seconds, his tenth Manx Grand Prix win, from McGurk (1:26.11.49/105.059mph) with Mateer (1:26.57.73/104.128pmh) securing the final podium place and a Yamaha 1-2-3.