He took part in the Four Hills Tournament for the first time at the age of sixteen . From the mid-1970s until his retirement after the 1980/81 World Cup season , he was one of the world's best in ski jumping. At the Four Hills Tournament 1974/75 he was fifth overall, and sixth the following year. At the ski jumping World Cup , which was held for the first time in the 1979/80 season , he was third in the overall standings, and in the World Cup jumping on January 26, 1980 on his home hill in Zakopane, he achieved his only victory on an international level.
He celebrated his greatest successes on the national level: on the large hill ( K90 ) Bobak was Polish champion in 1976, 1978, 1979 and 1981, in 1975 and 1977 runner-up and in 1980 third; on the small hill ( K70 ) he won in 1976, 1978, 1979, 1981 and was second in 1975, 1977, 1980.