At the suggestion of John Lennon, Billy added the "J." to his stage name to give it more appeal, the "J." being in memory of John's mother, Julia, and for his newly born son, Julian.
Upon handing Billy a tape of what was to become the first in a succession of smash hits written especially for him by John Lennon and Paul McCartney, John apologized for the quality of the recording. John had to record "Do You Want To Know A Secret" in the toilet, as it was the only place where be could find any peace and quiet. With this tune, Billy and his backup group The Dakotas, claimed the #1 chart spot in England, topping the Beatles themselves.
The Lennon/McCartney compositions: "Bad To Me", "I'll Keep You Satisfied" and "From A Window", all became international million sellers for Billy, and appearances on "The Ed Sullivan Show", "Shindig", and "Hullabaloo" rocketed Billy to a place in Rock and Roll history as the pioneer of the British Invasion.
For his follow up to the chart-topping single "Bad To Me", Billy opted to record "Little Children", a song written by two Americans, Mort Shuman and John Leslie McFarland. Despite strong opposition from Brian Epstein and producer George Martin (who both felt that Billy should stick with another Lennon/McCartney song), Billy stood firm and his insight proved correct. "Little Children" became his biggest selling worldwide hit.
With just a few more minor successes following that hit, the group continued recording, but The Dakotas split from Kramer in 1968. During the '70s, Kramer toured with a different Dakotas band, with sell-out concert appearances and standing ovations in England, Australia, Germany, Scandinavia and throughout the United States. In about 1983, Kramer released a single called "You Can't Live On Memories" / "Shooting The Breeze", which failed to chart.
Billy J. Kramer had always felt that America was the home of Rock and Roll, and he finally fulfilled a long time ambition in 1993, to move to the United States. He took up residence on Long Island, New York with his wife Roni, his two sons, and his dog Elvis, and continued to tour as a nostalgia act.
In 2005, Billy recorded the song "Cow Planet" for Sandra Boynton's children's album, "Dog Train". A long time fan of Kramer's, Boynton had sought him out for her project because she said that the first album she ever bought was "Little Children", when she was 11 years old in 1964.