Hank Aaron has been everybody's hero. He was the good guy, modesty mixed with greatness. The man who hit more home runs than anybody else, including Babe Ruth, the legend.

There were cheers from everywhere on the night of April 8, 1974, when his homer No. 715 sailed out of the Atlanta park.A new champion, with no trace of the kind of resentment stirred when Roger Maris surpassed Ruth's record of 61 for a single season.

If anybody was to break a Babe Ruth record, let it be Aaron. That was a consensus.

But it was a curious turn that the nice-guy story of Hank Aaron took last week. He was in a snit. He sulked and he whimpered. He diliberately snubbed a luncheon testimonial in New York to honor him as the man who contributed baseball's greatest moment of the decade. He didn't show up, deliberately and without warning to anybody.

Instead, he sent his agent to read a telegram to the assembled company and deliver some gripes. The first of these seemed to concern Commissioner Bowie Kuhn, who was left holding a trophy without a recipient. In so many words, Aaron said he was getting even for Kuhn's failure to attend the game when he hit No. 715.

"I remember the commissioner did not see fit to attend," Aaron said. "It was a slap in the face to me and to Atlanta fans."

He left no doubt he had nursed an old grudge. "I've been waiting for six years to express this." It was the sweeter, he indicated, because Kuhn had personally asked for the honor of presenting the trophy that he was now not accepting.

Pretty small stuff by the man everybody used to cheer. For the record, Kuhn had attended the game four days earlier when Aaron hit No. 714, tying Ruth's record. Was he supposed to abdicate his other duties to follow Aaron as his personal baseball commissioner until No. 715 was hit? In some reasons, there had been gaps of as many as 10 days between Aaron homers.

The whole outburst was uncharacteristic of Aaron, including gripe No. 2, in which he said, "I do not agree with the selection of Pete Rose as player of the decade." Aaron said he felt the award should go to himself. The awards were made by Baseball Magazine after a poll of 80 writers, broadcasters and executives.

"If you go by the record, it speaks for itself," Aaron said. "I think the things I achieved overshadowed anything anyone else did in that period. I've heard that most of the writers voted for Rose and that most of the executives voted for me, but I'm not sure of that." What he can be sure of is that the same electorate voted in both categories.

If it is more recognition that Aaron seems to crave now, he should read up on the unwide acclaim Babe Ruth got in 1927 for breaking his own mark of 59 homers in a season. No TV cameras carrying the message, with repeats to the world. No featured place on the night news of all three networks that did not then exist. No 52,000 fans in the stands.For Ruth, that day, 50,000 empty seats in Yankee Stadium, only 10,000 in attendence. It was no big deal. It was rated as the No. 3 story in The Washington Post pages next morning. The Babe didn't complain that Kenesaw Mountain Landis, the commissioner, was in Chicago counting his toes.

Aaron's telegram also voiced his gripe No. 3, that organized baseball wasn't giving black players proper job opportunities as managers and front-office executives after they retired from the game.

Here, Aaron was on solid ground at last. The only two black managers hired, Frank Robinson, and Larry Doby, had short terms with Chicago and Cleveland before getting the same treatment as white managers whose teams finish far back. But it is to baseball's shame that no others were given an opportunity despite the heavy percentage of black players. Aaron is a vice president of the Atlanta Braves, but so few others are in front-office posts that it is transparent tokenism.

Baseball has much to answer to, in this department, and Aaron's protest is a reasonable one. But he should have made it in the form of an uncomplicated and loud demand for better jobs for blacks in baseball, without getting it loused up in his own gripes. He didn't need to put it in the framework of how Kuhn was mean to him, and how he was such a better ball player than Pete Rose. And how his father could lick Pete Rose's father.