Weinert had other plans. He was the defending 500cc National Champion, having won it the year before while riding for Kawasaki. Now he was with Yamaha and he won the opener in Kansas. Karsmakers would win Round 2 in Mexico, New York. Brad Lackey won the third race at Lake Sugar Tree in Virginia, but he was not in the points chase because he missed the first rounds of the series while campaigning the 500cc World Championship in Europe. Grossi would win the fourth round at Ravenna, Ohio. New Orleans would be the fifth and final round of the series, with five guys still in the title hunt.

Adding to the pressure-cooker vibe was a faulty starting gate at the Motocross West track that caused a red flag on the start of the first 500cc moto. On the restart Kawasaki’s Gary Semics snatched the lead while Suzuki’s Grossi got an unlucky break—another rider ran into the back of him, then got caught in his rear wheel. He would finally get going toward the back of the pack, and he would have to scramble to finish sixth. But the winner was Husqvarna’s Lackey. In close order behind him came Weinert, who put on an energy-sapping charge to second, then Karsmakers, Semics, Howerton, Grossi and Stackable.

Due to earlier delays, not to mention the stifling heat, the decisive final moto would be run late in the afternoon. This time Howerton grabbed the holeshot on his Husqvarna, only to be overtaken by the veteran Karsmakers, back then the highest paid rider on the AMA circuit with a Honda contract reported to be worth $70,000. Grossi would again suffer a cruel blow on the first lap, this time running into another rider and crashing into a snow fence.

Up front Karsmakers would be run down by Lackey, who made a very aggressive pass on Pierre that would later lead to a protest. The Dutchman would have more to protest about in a few more laps when DiStefano passed him, and then the two of them collided over a big jump, knocking both to the ground. Karsmakers’ front brake perch broke off in the crash, causing him to have to pull into the mechanics’ area to get it snipped off.

Lackey was leading up front, yet the track was so dusty that the air filter on his Husqvarna clogged to the point of choking the bike completely, causing his bike to seize. That put the Texan Steve Stackable in the lead, and the partisan crowd was pleased to see a neighbor from the Lone Star State leading. Stackable got help when Bultaco’s Marty Tripes went past Weinert for second. Weinert, who appeared exhausted from the heat and the effort, slipped even further back when Semics went past him. The Jammer could not afford to lose another spot, and as the race wore on, he hunkered down and gave it all he had to stay in fourth. Somehow, the Jammer ended up winning the title and the overall with an unlikely 2-4 moto score.

“We are going to tear up New Orleans tonight!” Weinert told Cycle News after the race. “That was one of the most nerve-wracking days I ever spent. Wow, I don’t believe it!”

Weinert would beat out Stackable for the 500cc Championship, with Karsmakers third, the hard-lucked Grossi fourth, and Howerton fifth.

One year later the New Orleans 500 National in 1975 was the basis for the MX documentary One Chance to Win by a young filmmaker named Charles Bush. He followed the five-round circuit in a van, just like the riders and mechanics did back then, filming them on and off the track. It’s an intimate look at what motocross life was like in those nascent years, and definitely worth having in your video library. Bush completed the film in 1976 but the distribution company he was working with went out of business. The film was never widely released until the producers of The Motocross Files TV show came upon it and restored it. You can now buy it on DVD or find it on Netflix.

Here are more images from 1975, courtesy of the Dick Miller Archives.