His seventh place with a final lap average of 130.872mph proved the V4-powered Norton is finally a TT contender with even more to come.

To underline his performance he beat Kiwi TT legend Bruce Anstey, who was racing a Honda MotoGP V4 replica RC213, to finish 9.5secs ahead.

Winner Michael Dunlop blew the circuit apart with a new record of 133.393mph and the first sub-17 minute lap. While Dunlop eased off very slightly on the last run down the mountain, Johnson and Anstey were locked in a stopwatch duel.

Johnson had come from 13th on the first lap to ninth by the start of lap two.

He was then locked in a time trial with Gary Johnson, closing down the BMW rider with a top speed of 190mph down Sulby Straight.

Johnson’s Norton was the second fastest bike through the speed trap on a straight that third-placed John McGuinness had earlier described as “like a motocross track this year”.

By the first refuelling stop “Davo” Johnson was just 0.8sec behind Johnson.

By Ramsay Hairpin on lap three “Davo” was four seconds ahead of Johnson after another 190mph run down Sulby Straight (second fastest again).

On lap four there were just 7/100th of a second between the pair and they battled it out to the next pit stop.

“Davo” gained 8.4secs after this stop while Anstey launched a late challenge.

Before the 380km race Anstey had described the after effects of a practice week crash.

“I feel like I’ve been run over by a bus but I’ll give it a go,” he said.

And so last year’s Superbike race winner put the hammer down, overtaking Gary Johnson on the time sheets on lap six and shaving a 10-second deficit to “Davo” at Ramsay Hairpin to seven seconds at The Bungalow.

The run down the mountain was a race of nerves but Johnson maintained his cool and his lead to bring the V4 Norton across the line to its best finish in the five years it has been entered at the TT.

Johnson will next race the Norton in the Senior TT on Friday. He will contest several other races during the week, starting with the SuperStock on Monday.

Meanwhile, fellow Aussie and former Norton racer Cameron Donald retired his Honda at Quarter Bridge on lap one. The other exotic entry, the two-stroke Suter, also retired during the race.

winner

Top three of the RST Superbike TT Race (3rd) John McGuinness, (1st) Michael Dunlop, (2nd) Ian Hutchinson

By Hamish Cooper