The Trail Blazers scored 63 points in the second half to pull away.
Miles, who was 0-for-11 in Portland's preseason opener and had just six points in its second contest, was 7-of-9 from the floor and added four steals.
Miles and offseason free agent signee Richie Frahm scored six points apiece in a 12-0 run that opened the fourth quarter and gave the Trail Blazers a commanding 102-66 lead.
Damon Stoudamire scored 18 points and Zach Randolph and Shareef Abdur-Rahim each added 17 as Portland shot 61 percent. Randolph scored 10 points during a 16-8 run to start the second half.
Jason Kapono scored 17 points off the bench and Gerald Wallace
and Primoz Brezec chipped in 12 apiece for the Bobcats.
First-round pick Emeka Okafor scored four points and grabbed
four rebounds in 16 minutes.