Four score and seven times a month, a New Yorker must defend his city against charges it is rude, pompous, obnoxious and the kind of place where a George Steinbrenner is symbolic of forces that would turn the planet into a pin-striped asylum. The customary defense is that Georgie Porgie isn't a New Yorker at all but is from Cleveland and thus was born naked of the savoir faire that distinguishes the world's elite.

It is, then, a boatload of chuckles to read the papers on this America's Cup stuff. Some Sundays, to see how the other half lives, an old shortstop reads the boat-sale ads such as: "Tahiti Ketch 30' 1939 mahogany on oak, fully equip, $165,000." It all sounds so stuffily distinguished, with jibs and spars and mainsails, when, glad news indeed, it can be as much lowdown fun as pine tar on a ball bat.

At Newport, R.I., home to Claus von Bulow and the America's Cup, there has been a James Bondian caper involving an underwater photographer in a wet suit. There have been revelations of telegrams from the New Yorkers trying to steal secrets. And the distinguished stiff necks of the New York Yacht Club have out-Steinbrennered Steinbrenner by screaming foul before the game even starts. Next thing you know, some grizzled admiral will punch out a marshmallow salesman.

Boats representing the United States have won the America's Cup every year since the New Yorkers invented it. Now there is an Australian boat that might spoil their fun. With defeat a possibility for the first time, the New York boat boys have thrown savoir faire overboard. Steinbrenner is a pine-tarred milquetoast next to these stiff necks in topsiders.

The New Yorkers make dark accusations that Australia II is an illegal boat. They suggest that its keel, with configuration that is kept secret, is shaped so that when the boat heels over, the keel reaches even deeper. This makes the boat go faster than it would with a traditional keel.

The Australia II already has passed two inspections when only one is routine. The New Yorkers are asking the international yachting authority to do a third measurement. They are worried by Australia II's 38-4 won-lost record in training exercises against boats preparing to meet the American representative, either Freedom or Liberty.

Such an overwhelming superiority in training exercises, the New Yorkers say, shows that Australia II "threatens to unfairly control the 1983 competition." Dennis Conner, the skipper of the American defender, said the Aussies "will likely win the America's Cup in September." There is even suspicion that Australia II purposely has lost races and kept others close to sustain the illusion of sporting competition.

Because the Australians keep their boat's keel wrapped in canvas at the dock, no one has seen it but the Aussies. A Canadian in a wet suit, carrying a camera, was arrested swimming near Australia II. Police confiscated his film, which presumably was rich with pictures of the mystery keel.

Two days ago the Australians revealed knowledge that the New Yorkers had tried an end run to get information on their keel. The Australians gave the press copies of telegrams between the New Yorkers and a Dutch tank-testing company that had tested the Australian design.

The New Yorkers, hemming and hawing, said they weren't trying to steal the keel design for their own boat. They said they wanted to build it for a second boat to see how they would do against it in competition.

When the Dutch refused to give the Australians' secret to the Aussies' competitors, the New Yorkers two days later demanded a new measurement of Australia II.

The stiff-neck boat people, not willing to concede a design victory any more than Steinbrenner would concede Baltimore's organizational superiority, say the the mystery keel on the Aussies' 12-meter yacht makes it a 12.5 meter.

We could go into how they measure yachts (if you park it downtown and you need to feed 12 meters, it's a 12-meter job). But it is enough to say that a big sailboat is faster than a small one. Think of Al Unser taking his Indy car to the Kentucky Derby and you get the tone of the New Yorkers' whining.

That the New York sailor boys should be in a whining snit at the prospect of losing the America's Cup comes as no surprise to anyone who read the letters to the editor in Sunday's Post. There was a letter from two New York congressmen, Mario Biaggi and Stephen Solarz, soliciting attention for their offices' Congressional League softball teams, "Biaggi's Bronx Bombers" and "Solarz System."

Without telling us how many times they fired their managers or how often they cried to the umpires about pine tar, the congressmen whined that The Post had failed to mention their teams. So they recounted the teams' won-lost records and said they had won three of four championships available. This information must be reassuring to those New York taxpayers who worry that the Soviets are stockpiling aluminum bats for a softball invasion.

Out of some sense of distinguished restraint, the congressmen added that, sure, they know softball's all in fun.

Being New Yorkers, being the creators of Steinbrenner, they couldn't stop there. "But hailing from New York--the City of Champions--we're speaking from experience when we say the most fun of all is WINNING!" the congressmen wrote.

As it happens, New York teams haven't won anything since the middle of Jimmy Carter's term, when the '78 Yankees won the World Series. Maybe the most fun isn't winning but whining about winning.