Most of Metro's 43 new articulated buses-the kind that bend in the middle as they go around curves-have been delivered by the manufacturer and will go into service June 17, the transit authority announced yesterday.

Members of the Metro board and staff officials took a ride around a downtown block in a demonstration of one of the buses yesterday, and most pronounced themselves impressed.

"I was riding right on the swivel (that hinges the two parts of the bus) and didn't even realize the flex of the thing," Fairfax County alternate director John P. Shacochis said.

Because the buses are several inches wider than permitted by Virginia law. They cannot run in that state. They also are 15 feet longer than a standard bus, seating 61 passengers instead of 47. They cost $173,500 each, with 80 percent provided by the federal government.

Metro, along with transit agencies in 10 other cities, joined in buying a total of 298 of the buses chiefly because they save money in driver wages. At least one city, Seattle, pays premium wages to drivers of the new buses, but Metro has no plans to do so.

The Washington buses will be assigned chiefly to the Benning Road line, which has few curves. as well as to rush-hour trips on the Connecticut Avenue line. Metro general manager Theodore C. Lutz said some of the buses may be used on other routes prior to the official June 17 starting date.

At its meeting yesterday, the Metro board took these actions:

It agreed officially to pay Richard S. Page, a federal transit official who will succeed the resigning Lutz on May 7, a salary of $60,000 a year, $2,000 more than Lutz. Page also will receive $6,000 a year in deferred compensation rather than participating in Metro's pension plan. This reflects the possibility that Page might leave Metro before he gains full pension rights.

It voted to pay Cubic-Western Data Corp., manufacturer of Metro's Farecard equipment, nearly $1.6 million of the $2 million that had been withheld until the equipment reached reasonable standards of reliability. The balance will be retained indefinitely. Prince George's County director Francis B. Francois said future procurement contracts will have tighter standards.

It approved the establishment of a new rush-hour bus line, effective April 30, between the Saratoga-Newington area, south of Springfield in Fairfax County, and the Pentagon.

It adopted a new pay scale containing 32 instead of 18 grades for Metro's 1,165 salaried employes. Officials said the new pay levels will permit closer comparability of wages with employes of the area's local governments.

L. J. Sheridan, president of Local 2 of the Office and Professional Employes Union, which is trying to organize Metro employes, protested the action, contending that an employe promoted from his current grade to the next highest will receive only a 6 percent wage increase instead of the current 12 percent. The new salary scale does not change Metro's curent minimum of maximum pay. CAPTION: Picture, New articulated buses will begin serving the Maryland and District areas in June. The width of the buses, by existing law, prohibits use on Virginia's streets. By Fred Sweets-The Washington Post