Which ship to New York?

I'm tracing an emigrant with a special name: He was baptized Knud Olsen Haavi, 1854, Slidre, Valdres, Norway. He's registrated as en emigrant with the same name May 13 1881 on the ship ROLLO. Arrival NY The problem is; did he change ship in England or did the ROLLO go to NY?? If I could follow his tracks I hope I could find the name he was "given" in the US, and then trace him in US archives. It could have been Knud/Knude/Knute O. Haavi/Haavie/Hove/Haavig....! Best regards from Norway, Tor