As the fight crowd begins to flow into this festive city for Friday night's World Boxing Association heavyweight title fight, one question dominates most coversations.

Is Muhammad Ali, at 36, capable of defeating the younger (25), faster and stronger champion, Leon Spinks?

Considering Spinks' impressive performance in upsetting Ali last February in his eighth professional fight, and Ali's sluggish victories over Earnie Shavers and Alfredo Evangelista in 1977, logic is against the former champion.

But Ali, even at this stage of his career and life, has the determination and competitive fire for yet another upset. But one wonders if the skills and reflexes are still there for him to pulls this off. If he does, he will have regained the heavyweight title for the third time in a career that has seen him win 55 of 58 fights.

If Ali's skills are questionable, so is Spinks' decision to his chosen profession and training methods.

Spinks has been late for several scheduled workouts here and canceled one after having an incisor tooth knocked loose in the ring. The tooth was removed by a dentist. He says his wife previously removed one with a piece of string.

Ali, as usual, owns the audience at sparring sessions, literally on stage, complete with gallery.

But Spinks has his own generation, at least temporarily, with the "funk-a-delic." heavy metal" music he personally selects for training sessions.

What Spinks is up against is what quarterback Billy Kilmer of the Washington Redskins was up against when, because of no fault of his, folk hero Sonny Jurgensen was hurt during Kilmer's first year in town.

A generation of fans cannot accept Spinks owning the title that belonged to Ali. As the former champion said himself the other day: "I shocked the world (not just local police stations). I fought the draft . . . I became a Muslim."

Ali has several Rolls Royces and buses. He has an entourage that makes large hotels wince when they agree to pick up the tab to have Ali's party headquartered there.

Ali did not come out of a public housing project, as Spinks did. Spinks wonders about nobody ever caring about him until he won the title and then image-conscious critics all of a sudden expecting him to emerge as Jack Armstrong, All America Boy.

An associate of Spinks asked who would not have had a few drinks after sudden windfall and not have bought a few new, expensive things.

Ali didn't spar Friday, but Spinks did, one day after having his tooth removed. But there was criticism, rather than sympathy, when he stopped a round momentarily because he had just been popped in the area of his teeth by Leroy Diggs, who is a couple of inches taller than Spinks and about 50 pounds heavier.

Nor did Spinks pretend he was stoic about it afterward. Asked how he could withstand such pain, he said, "It hurt a great deal, but I need it (the timing and the familiarity with the punishment of the sport). Because of the pain, I laid off one day and did no running. That's why I wasn't sharp today."

There was comment by ring observers that the champion got hit with too many punches by three opponents.

The first thing that one hears upon coming to town is that Spinks and his followers upset the kitchen staff by insisting on inspecting food, in fear of being poisoned.

But fight observers forget that Ali brought his own cook and still has civil rights activist and food faddist Dick Gregory preparing, health diet and vitamins for him.

There are always tales brought back to Spinks of what Ali is telling the media about him. For insistance: "Spinks is too small; that's why he isn't running. He's drinking beer and eating hot dogs to gain weight. He's not a heavyweight."

That, despite the fact that Spinks was wearing two layers of training clothes to keep his weight in check.

Ali sounds as though he has a "psych" job to do on himself wen he pinches the wrinkles in his stomach. But he insists he is already down to 218 after weighing 226 for his loss to Spinks. Ali says: "I'll come in at 215, dancing. "I'll knock him out in style. It won't go over 10 rounds. There will be no rope-a-dope, no giveway of rounds. I'll begin popping him in the first round.

"He's a slapping, pitty-pat puncher.He's had only eight fights. I didn't train for him last time because of that. I underestimated him. My chest was big, my jaws looked big, my gut was big. Look at my jaw, my neckline, my breasts. They're trim."

The crowning insult to Spinks has been that although he whipped Ali, the former champion was made a 2 1/2-to-1 favorite as soon as they signed for the rematch, mostly on sentiment and wishful thinking by Ali's fans.

The odds were longer before their first meeting and didn't faze Spinks.