Suzi Perry and James Toseland dressed in bubble wrap to back a campaign to make every driving test include a question on motorcycles.
Presenter Perry and retired racer Toseland were also highlighting April 5 as the most dangerous day of spring for motorcyclists, according to Bennetts insurance.
They posed alongside TalkSport presenter Darren Gough at Elephant and Castle in south London, one of the worst accident black spots.
The stunt was aiming to generate signatures for a petition demanding the Department for Transport make a bike-related question part of every driving test.
Perry said: “With almost 34,000 signatures to date, the petition aims to raise awareness of bikers on Britain's roads.”
Sign the petition here.