TriMet took the extraordinary step of warning MAX riders to consider not buying a monthly pass for May, when it plans two weeks of disruptive track maintenance.

The $2.1 million project scheduled for May 8 through 21 will close a stretch of track along First Avenue, but the effects will echo throughout the light-rail system, as fewer trains will be able to pass through downtown.

Green Line trains will only serve the east side, while Blue Line trains from Beaverton and Hillsboro will turn around downtown. Yellow, Orange, Blue and Red line trains will all share the downtown transit mall, but each line will run fewer trains than usual.

TriMet said riders who choose to take MAX need to plan for an extra 30 to 45 minutes of commute time during the disruption, but it's advising riders to find another way to work. Bus service will run as usual, and shuttle buses will supplement the reduced MAX service.

The agency is also asking cyclists riding MAX to leave bicycles at home or park them at a station because space will be at a premium.

Expect extremely crowded, less frequent trains and longer trips—consider this if you plan on buying a May monthly pass — TriMet (@trimet) April 14, 2016

The warning not to buy May passes comes too late for some riders who buy their passes through an employee benefit program, for whom orders were due earlier in the month. Others who receive passes by mail received a notice in March.

The project is intended to shore up an aging section of track -- where several MAX trains flooded and were taken out of service after an October storm -- and improve MAX reliability systemwide.

-- Elliot Njus

enjus@oregonian.com

503-294-5034

@enjus