In the 1980–1981 season, Motzko played for the Dubuque Fighting Saints of the United States Hockey League where he had 20 goals and 16 assists.
Motzko served as general manager and head coach of the USHL's North Iowa Huskies from 1987 through 1991.
Motzko was named general manager and head coach of the USHL's Sioux Falls Stampede in 1998.
Motzko served as a men's hockey assistant coach at the University of Minnesota and was part of two NCAA Division I national championship teams in 2002 and 2003, and helped the Gophers win WCHA playoff crowns in 2003 and 2004.
[6] On March 26, 2010, Motzko led the Huskies to their first NCAA Tournament win in the West Regional at Xcel Energy Center.
On March 30–31, 2013, Motzko led the Huskies to a pair of NCAA Tournament victories over Notre Dame (5–1) and Miami University (4–1) at Huntington Center (Toledo) to advance to the first Frozen Four in school history.
He led them to the United States fourth-ever gold medal in the IIHF World Junior Championships.
[7] On March 27, 2018, Motzko was named the 15th head coach of the University of Minnesota, following Don Lucia's resignation.
Conference tournament champion Motzko, a native of Austin, Minnesota, Bob and Shelley have had three children, a daughter, Ella, and two sons Mack and the youngest Beau.
On July 24, 2021, Mack died at the age of 20 from injuries sustained in a single car accident in which he was a passenger in Orono, Minnesota.