Hundreds of bikers took a break from hell-raising on Sunday to be blessed by Pope Francis.
Wearing black boots, jackets and vests, the tattooed Harley-Davidson riders stuck out among the nuns, priests, school children and shorts-wearing tourists at an open-air Mass in St. Peter's square.
As part of a three-day celebration of the 110-year anniversary of the U.S. company that produces the "hog", riders parked their bikes along the broad avenue that leads up to the Vatican, and engines were still rumbling when the Mass started.
It was unclear whether Francis's homily about celebrating life could have been aimed at the obsessive Harley fans.
Francis cautioned that "power and pleasure", among other things, lead to God being "replaced by fleeting human idols which offer the intoxication of a flash of freedom, but in the end bring new forms of slavery and death."
On Wednesday, representatives of the motor company, which is listed on the New York Stock Exchange, met the pope and gave him two Harley-Davidson Inc. motorcycles and a leather jacket.
A 40-km (25-mile) Harley-Davidson parade from the port city of Ostia through central Rome on Saturday prompted some residents to complain about the traffic and noise. Ten bikes were involved in a serious accident on the capital's ring road.
Consumer association Codacons said it would file a complaint against the event's organisers, and criticised the pope for giving the company free publicity.
"Since it was a marketing event, the pontiff would have done well to avoid giving free advertising to a well known brand, especially considering the damage done to the city and its inhabitants," Codacons said in a statement.