Dayes signed with the 49ers' practice squad Tuesday.
The 2017 seventh-round pick by the Browns was waived by the team Sept. 2. Dayes appeared in all 16 games for the Browns last season and had five carries for 13 yards while adding four receptions for 29 yards. He was also active on both sides of the ball on special teams, registering 18 kickoff returns for 437 yards (24.3 average) and eight tackles.