President George W. Bush greeted Rolling Thunder bikers on the South Lawn of the White House Sunday. After brief comments, the prez ditched his jacket and tie to pose for photos in a biker vest presented to him by Vietnam vet Artie Muller, president of Rolling Thunder. Bush thanked Muller with a hard-but-friendly slap to the shoulder.

Muller winced. Nerve damage from a shrapnel wound gives him a ton of pain whenever his shoulder is touched. He even wears metal spikes on his jacket to remind people not to grab him there.

“I do that every year, don’t I?” Bush said.

Muller nodded. “Yes.”