She did up the helmet strap under her chin.
He had forgot to fasten his helmet strap, and nearly lost his helmet at the start of the race.
One rule is to unbuckle the helmet straps after dismounting to prevent anyone from jerking the officer's head around.
I knelt and undid the helmet strap, and tried to pull off the headpiece.
He tightened his helmet strap after adjusting his throat mike.
"First time out this year," said Jonathan Beale, a 36-year-old college professor, who stood adjusting a helmet strap.
The mouth above his helmet strap looked as if it hadn't cracked a smile since the early eighties.
Along with the design of the seat belt, helmet straps have been designed to increase the safety of the driver.
Someone cut his helmet straps and removed it before several of them quickly dragged him to the shade of the first aid tent.
He pulled his chin down to test the tightness of his helmet strap.