What is the Rule on Late-Race Red Flags and Restarts? Detroit 250SX Main Event Incident Explained
Everyone watching the 2025 Monster Energy AMA Supercross Championship round at Ford Field in Detroit, Michigan, saw a red flag came out late in the 250SX main event. Battling inside the top ten, Cameron McAdoo got wild in a run through the whoops, bucked right, and caught his handlebar on his left cheek. Down and clearly shaken up by the crash, the #50 needed medical attention, so the Alpinestars Medical crew Ran onto the track. In order to allow proper treatment and care for McAdoo the race was red flagged.
Seven seconds remained on the clock for the 15-minute-plus-one lap main event. So, what was next? Was the race over? Was race leader Max Anstie the winner by default? Lots of fans in person, watching at home, and commenting on social media were confused and unaware of what would happen next. Let's explain what happened and why it played out that way.
The Old Rule: Prior to the 2023 season, the aforementioned would have been the case. Over 90 percent of the race was completed, and the old rule read that a red flag that late in a main event would mean the race was finished. Anstie would be the winner, Levi Kitchen second, and RJ Hampshire third, they would have done the interviews, taken the podium photo, and moved onto the 450SX main event.
The New Rule: However, according to a change made prior to the 2024 supercross season, that 90 percent rule is no longer a thing. The new rule no longer applies at all, and the key now is if the lead rider has completed either less than three laps (full gated restart) or more than three laps (staggered restart).
Apparently, there was an outdated graphic used on the TV broadcast last week at the Tampa SX, which showed the old 90 percent completion, causing some confusion tonight. The AMA officials did not make this rule up on the spot - this is just the first time we have seen it put to use since its inception.
Why Change the Rule: Our Jason Weigandt spoke with the AMA after the race in Detroit. They cited that doing exact math on what constitutes 90 percent of a race that uses a mix of both a race clock and one additional lap leaves the door open to interpretation. Essentially, how much of a "percent" of the race is that one final lap that takes place after the clock expires? Changing to a race-clock only rule instead of using 90% makes the situation more clear, according to the AMA. With a new rule, the clock determines everything.
There were seven seconds left on the clock when the red flag came out in Detroit. As we all saw, the riders were lined up single file for a staggered restart to finish the race.
Why a Red Flag: Weigandt also asked the AMA what led to a red flag. When McAdoo first went down, he was attended to by one medic. The yellow caution flag was shown. Once the medic assessed the situation and determined more medics would need to access the track to help McAdoo, the red flag came out.
How was the amount of racing left determined?: As you will read in a moment, the adjusted rule prior to 2024 now reads that "The race will be restarted with the remaining number of laps and/or time" BUT continues "In all cases, the remaining race distance following a restart will be at least three (3) laps."
Because there was barely any time left on the clock (just seven seconds), this race was a three-lap sprint to finish the race. It was going to be a green-white-checkered flag situation often seen in NASCAR races.
However, remember the rule says at least three laps. The start in Detroit was less than half a lap away from the finish line, so the first run through the finish could not be considered a full lap. Thus, the AMA threw the green flag after the first full lap. After the restart, the riders did about three and a half laps, which was needed to put them over the at least three laps rule.
When the race was restarted, Kitchen used the restart to his advantage, eventually taking the win. Anstie handled the situation with class. After two rounds, Anstie leads the championship. View the 250SX East Division Championship standings.
The following text was in the post-race race recap press release from Feld Entertainment, basically the information I will note directly from the rulebook but in a short, cleaner fashion. Feld Motor Sports confirmed this information came directly from the AMA. The press release note read:
"Note: The AMA’s re-start procedure after a red flag was updated prior to the 2024 season. The rule states that if the leader has completed at least three laps, and if there is any time remaining on the race clock, the riders line up in a staggered-position on the start straight. A green flag re-starts the race, and the remaining race duration will be, at minimum, three laps."
Verification: Now that the race is done and dusted, let's pull out the rulebook to verify this information. In the 2025 AMA Supercross rulebook (click here to view), the following rules read (note, our bold):
1.8.11 RESTARTS AND RED FLAG PROCEDURES
a. Any race start or restart will be considered an official part of the event even if the start or restart does not result in a lap being completed by the leader. Therefore, any infractions will be deemed valid and ruled upon accordingly.
b. In all cases, the remaining race distance following a restart will be at least three (3) laps.
Further on down is where this rule applies (again, our bold):
l. When a race is stopped after the leader completes three (3) laps but prior to time expiring on the race clock, the following procedures will apply:
1. A red flag will be displayed, and the Red Flag Downtime period will begin.
2. All Riders must stop racing and proceed with caution to the starting area directly in front of their original starting gate or other area as directed by Race Officials.
3. Repairs or adjustments may only be made in the starting area.
4. The race will be restarted as soon as possible from a staggered standing start in the starting area.
5. Scoring Procedures
i. Scoring will revert to the last lap completed by all active Riders on the Lead Lap. Riders involved in the red flag will be considered active Riders for the purpose of establishing the running order, i.e. if all active riders have crossed the finish line to complete their third lap and are working the fourth lap at the time of the Red Flag, the starting order would be set with the order from the completion of the third lap.
ii. Total race time will be stopped during the red flag period and will resume when the race is restarted. Only green flag periods will be used to calculate total race time.
iii. The race will be restarted with the remaining number of laps and/or time.
Now that this rule has been implemented and put to use once, everyone will know what to expect if a situation like this were to come up again in the future.
You can watch the full 250SX main event highlights below.
