Harris, who suffered the knee injury in the first half of the Flyer's (1-2) season opener, was the anchor of a Dayton ground game that carried the bulk of the load offensively. Dayton passed for just 75 yards in the win, but ran for 172.
The Flyers jumped to a 14-0 halftime lead. Robert Morris (0-3) cut the lead to 14-7 early in the third quarter, but got no closer.
The win marked the 400th straight game that Dayton had not been shut out, the longest current stretch in the NCAA. The team's last shutout was a 9-0 loss to Marshall on Oct. 16, 1976.
For the Colonials, Donte Jeter caught four passes for 113 yards and a touchdown.