If the Kentucky Derby is a two-minute horse race that gives 131,859 people an excuse to gussy up in their party duds and drink bourbon with weeds in it, then surely Muhammad Ali, a hometown hero here for his first Derby, would have a high old time today.

Alas, Ali was morose.

"No privacy," said the three-time heavyweight champion, slumping in a chair trying to be invisible on the sixth-floor Millionaire's Row of exclusive box seats. "Handshakes all the time. Autographs. I ain't having no fun. Can't have fun. I ain't the normal human being. I'm the most famous person on earth."

It turns out his wife dragged Ali to the party.

"I don't gamble and I don't like horses, but my wife wanted to see the Derby," said Ali, who grew up three miles from Churchill Downs without ever coming over to see what he remembers as "just a horse race."

Ali is a minority of one here today.

Perhaps alone in a reckoning of extraordinary sports events, the Derby is, in fact, a party. Customers at the World Series come with passionate attachments to the combatants, just as Super Bowls draw zealots from both sides. The patrons at the Masters have their favorites, and grown men go to Indianapolis wearing caps with A. J. Foyt's name on them. At the Derby, however, practically no one knows anything about the horses.

That's all right, because no one cares, either. They're here to have fun, not study fractions. From the zany Woodstockian crowd of college kids in the infield to the velveted ladies and deodorized swains of Millionaire's Row, you could torture the lot of them with Pink Floyd overtures and not learn the location of Rockhill Native's fetlock.

Here we are with Mike Carducci, 24, a beer distributor from Buffalo. We are in the infield, where by race time more than 80,000 brave souls will have taken the sun and enough beer to float Louisville to Texarkana. The infield is patrolled by police and national guardsmen who make 100 arrests on a normal Derby Day.

"Nice outfit, Mike." (For these without color sets, Mr. Carducci's Derby outfit is a pair of green suspenders holding up a barrel. He also wears a blue cap, but nothing else, so far as your intrepid reporter cares to find out.)

"I lost every cent I had playing these damn horses," Carducci said, extending his arms, palms up in the plaintive sign of a horseplayer who has lost everything.

Actually, Carducci loves a party. He'd never been to the Derby. So he found this barrel, strapped it on the back of his Fiat for the 9-1/2-hour drive from Buffalo and walked into the infield today with a plan. He would give a girl a peek down the front of the barrel if the girl paid with a kiss.

"Already got a hundred kisses," Carducci said.

About then, a very pretty girl, Shelby Reeves, 22, of Louisville, sneaked a look down the back of the barrel.

Carducci said, "Oh, my, I'm soooo embarrassed."

And Miss Reeves said, smiling ever so sweetly, "You should be."

"Tell us, Mike, which horse will win the Derby?"

"I think it all depends on who makes the best pit stops," Carducci said.

The infield at Churchill Downs on Derby Day is 25 acres of sex. Gay Talese would love it. "Girls, Get Naked Here, Expert Assistance Available," a sign said. The average guy in the infield wears no shirt and is three-quarters smashed; the girls are different -- some of them wear shirts. iThere are more passes made here on Derby Day than the NFL tries in a season.

Here we are with Buck Stahl, 20, a construction worker from St. Henry, Ohio. For the third straight year, he and his buddies have set up a S*M*A*S*H unit near the far turn of Churchill Downs. Stahl calls himself "Hawkeye," after the surgeon in M*A*S*H.

"Need an operation?" Stahl said to a passer-by.

"What's that stuff?" the passer-by asked, pointing to a plasma-like fluid suspended in a plastic bag.

"Sheven and sheven," Stahl said. He teetered a bit from the exertion of moving his lips. He had been anaesthetizing himself much of the morning, he said, and he thought it was beginning to, by God, kick in. "You'd be shurprised how mush longer the patients live," Stahl said.

Darth Vader, Superman, Santa Claus and a guy whose hardhat had antlers also moved through the infield crowd. This being Kentucky, an entrepreneur set up a basketball hoop and charged 50 cents for two shots; you won $1 if you made both.

"Later it gets today, after the sun and the beer," said Jerry Eaves, a guard on the University of Louisville national basketball champions, who was working at a photo stand, "the bigger a killing that guy will make."

If the pursuit of love, or a reasonable facsimile, shared center stage with the chugging of beer, it should not be said this crowd was without redeeming social value. Your intrepid reporter felt like an alien being visiting Peoria, so strange was his get-up of coat and tie in this world of pornographic T-shirts. And then he saw it: another tie.

"I always wear a tie to nice parties," said Marty Ruhl, 22, of Des Moines.

What Marty didn't wear was a shirt.

By now a guy was thirsty. Luckily, reportorial responsibility and thirst collided just as the reporter bumped into Whitney Leavell, 25, of Lexington, Ky., who in his white outfit was carrying around a 24-glass tray of mint juleps, $3 a pop.

"A good salesman will sell 25 of these trays today," Leavell said. "There are 100 of us working." Putting the pencil to that, and adding in a guess at the waterfall of bourbon served in various bars here, one supposes that more than 100,000 mint juleps were swallowed today.

A mint julep is a shot of bourbon with a twig of mint and a barrel of sugar in it. It's a traditional Kentucky drink that most Kentuckians consider as their penance for enjoying themselves so much on Derby Day. Today's mint julep, as all of those before, tasted too, too sweet.

Without the julep, and without the delightfully antiquated Churchill Downs -- an asymmetrical, wood-and-brick, rambling plantation house of a betting palace -- the Derby would be, as Ali said, just another race. Take away the traditions of juleps and colonels, put the race in an antiseptic steel train depot, and what you have is the eighth race at Aqueduct.

John Kovin now knows that. He's a lawyer from Washington who with his wife, Betty, and Miami Dolphin owner Joe Robbie is coowner of a 2-year-old thoroughbred named Certitude. Here for the first time, Kovin is entranced. And he's dreaming. "If everything goes well, I'd like to have Certitude here next," Kovin said.

"You see those twin spires of the grandstand, it's like going to Washington for the first time and seeing the White House," Kovin said. "You get such a feeling of history."

Kovin was a smitten man.

"You feel," he said "like you should have been here a long time ago." CAPTION: Picture 1, Kentucky Derby field of 13 charged from starting gate in a bunch; Picture 2, but Genuine Risk was a length ahead of Rumbo and another length in front of Jaklin Klugman at the finish; Picture 3, In winner's circle, Genuine Risk jockey Jacinto Vasquez accepts floral honors for first filly victory in Derby since 1915; Picture 4, Churchill Downs class extends to infield crowd where chandelier and blender add to comfort and good fellowship of Indiana group among 131,859 in attendance for 106th run for the roses. Photos by UPI and AP; Chart, Kentucky Derby; Copyright (c) 1979, by Daily Racing Form, Inc.