I think some punk guys were jokingly saying "Nice day for a walk" as a naked Arnold walked up to them. Arnold flatly returns the same line before suddenly asking the group to take off their clothes.
I had the two movies mixed up as well until I went back and watched them.
First movie: Punks: "Nice night for a walk, eh?" Arnold: "Nice night for a walk" Punk1: "Wash day tomorrow! Nothing clean. Right?" Arnold: "Nothingcleanright." Punk2: "Hey, I think this guy's a couple cans short of a six-pack" Arnold: "Your clothes, give them to me. Now."
Second movie: Arnold: "I need your clothes, your boots, and your motorcycle."