Who is che guevera’s friend who accompanies him in his road  trip by motorcycle as described  in a jorge drexlers song?
Al otro lado del río "Al otro lado del río" (English: On the Other Side of the River ) is a song, written and performed by Uruguayan singer Jorge Drexler for the film "The Motorcycle Diaries" (2004). Besides the film's soundtrack, it can also be found in Drexler's seventh album "Eco"; in the soundtrack the bassist Jeff Eckels also performed.
Viadera The viadera (] , Occitan: "viadeira" ] ; also spelled "viadeyra" or "viandela") was a lyric genre of Catalan and Occitan literature invented by the troubadours. It was a dance song devised to lighten the burden of a long voyage or to enliven the trip. It was a popular as opposed to "high" form and only infrequently used by cultivated poets. According to the Catalan Cançoneret de Ripoll, it was "la pus jusana spècies qui és en los cantàs" (the most humble genre of song there is) and elsewhere it is called "la més baixa espècie de cançons" (the most base genre of song).