B-c, sounds like it's a fairly simple signal timing issue, something the City's Signals folks have the ability to adjust as needed. If you can accurately describe the problem to them, they'll either fix it or give you a reason why they can't or won't.
Your person to contact is:
District: NW - except Pearl/River District
Tod Rosinbum
Tod.Rosinbum@pdxtrans.org
503-823-5573
Also, calling 823-SAFE would be an alternate route, albeit somewhat slower.