Jorge Lorenzo says Qatar Grand Prix MotoGP helmet issue was human error

Yamaha rider Lorenzo led much of the season-opener at Losail last month but tumbled to fourth in the closing stages after part of his helmet interior came loose and obscured his vision.

Lorenzo said a mistake by someone at his helmet supplier HJC Helmets had been identified as the cause.

"It was something that has never happened - an extraordinary failure, or mistake," he said ahead of this weekend's Grand Prix of the Americas at Austin.

"I hope this thing will never happen again so I can race in the future with 100 per cent vision.

"We guess it was a human mistake, which sometimes can happen.

"I made a human mistake last year [at Austin]

"We are a team - Yamaha, [race suit manufacturer] Alpinestars, HJC.

"This time it happened to HJC and I have to give 100 per cent support to them. Sometimes it can happen to Alpinestars, or to Yamaha or to some mechanic.

"We are a team and we are together 100 per cent."

Asked if he could provide more detail on exactly what had gone wrong, Lorenzo replied: "It's clear, isn't it? A 'human mistake' means one person made a mistake.

"I cannot specify what happened, I will keep it for ourselves. Sorry."

He underlined that he had full confidence in HJC for the future.

"The brand has my confidence," Lorenzo said.

"It's true that I was very frustrated at the end of the race - this is MotoGP and it's the best level in the world and everyone has to be professional.

"But we can make a mistake and we have to accept it."