John Kirkpatrick, 86, concert pianist who championed American composers. He taught music at Monticello College, Mt. Holyoke College and Cornell and Yale universities. After his 1973 retirement from Yale, Kirkpatrick remained curator of Yale's Charles Ives Archive. He was known internationally for promoting Ives, Carl Ruggles, Aaron Copland and many others. On Friday in Ithaca, N.Y.