SHANGHAI –The Chinese central bank guided the yuan to a fresh record high for the second straight day Friday, amid renewed pressure from Washington for Beijing to let its currency appreciate more and as a high-level Sino-U.S. economic dialogue approaches.

The authorities' aggressive move came despite growing consensus among investors that the days of fast yuan appreciation are over after Chinese leaders repeatedly described the currency as nearing fair value in recent weeks. A stable, if not weaker, outlook for the yuan is...