Motorcyclist died in five bike crash at race start
His motorbike, a Manx Norton 499cc, had been checked by a technician before the race and was found to be in good working order, the court was told.
Mr Clews had also taken part in a practice lap without any issues.
At the start line, just as the red lights went out to signal the start of the race, Mr Clews, who was in the middle of the second row of the grid, was said to look down at his bike and raise his right arm.
The court heard that “in a matter of seconds” he was hit by a motorcycle from behind and was thrown from his bike.
He was then struck by a further three motorcycles.
A marshal at the start line of the race told the coroner’s court that by the time Mr Clews had raised his right arm it was “too late to abort the race”.
Mr Clews suffered “multiple traumatic injuries” and received medical treatment at the track side.
He was pronounced dead at 11:23 BST, 21 minutes after the start of the race.
Another rider, a man in his 60s, was taken to the Norfolk and Norwich University Hospital by air ambulance, while three other riders suffered minor injuries.