BRADFORD'S Dean Harrison could not add a victory to his lap record on the opening day of the Isle of Man TT Races fuelled by Monster Energy.

The Silicone Engineering Kawasaki rider's lap record of 134.432mph (16min 50.384sec) in the delayed RST Superbike race incredibly came from a standing start, and he led by 18 seconds at the end of the first lap.

However, after setting the first 134mph-plus lap in TT history, he hit problems in the second half of the race and, after his lead had been cut to 4.6 seconds over the famous humped-backed bridge on lap four, he retired at Sulby Crossroads with mechanical problems.

Another retiree was Bingley's Ian Hutchinson (Honda Racing), who is on the comeback trail.

Michael Dunlop (Tyco BMW) won the race, 50.8sec ahead of Conor Cummins (Padgetts Honda), with James Quiller (Quattro Plant JG Speedfit Kawasaki) third.

Harrison's superb start meant that he was 3.7sec up over Dunlop at Glen Helen, with that advantage stretched to 5.6 by Ballaugh and 7.8sec at Ramsey.

By the end of lap one, the Bradford man was 11.3sec in front, and it was 14.7sec by Glen Helen second time around, and 16.3sec by the end of lap two.

That gap was maintained by the time Glen Helen was reached on lap three, but by the time the race was half done, Dunlop had pared back Harrison's lead to 11.5sec.

It was down to nine seconds by Glen Helen the fourth time around, but Harrison lost five seconds on the run from there, and his retirement soon followed.

That gave Dunlop a 40.5sec margin over Cummins, and there was also a large gap from second to third, with the positions of the leading riders remaining the same until the end of the race as Dunlop clinched his 16th TT victory.

Dean's brother Adrian (Kawasaki-Graham Barker) finished 33rd at an average speed of 117.225mph.

In the first Sidecar TT race, their dad Conrad was sixth with Andrew Winkle (Honda-Printing Rolling Services), with the victory going to Ben and Tom Birchall (Honda-IEG Racing).