How does a mass-start cross-country race start and finish?

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Accepted Answer

From the 2026 AusCycling Mountain Bike Technical Regulations, 3.01, 3.11 and 3.12: Staging: riders are staged no later than 10 minutes before the scheduled start, then a rider briefing is given on the start line that must be audible to all riders. Countdown: announcements are made at 5, 4, 3, 2 minutes, 1 minute, 30 seconds and 15 seconds before the start. The Start Commissaire then starts the race between 15 and 0 seconds, with no countdown announcement under 15 seconds. Mass starts use an audible device such as a starting gun or whistle. On the line: every rider must have at least one foot on the ground and may not lean on fences, other infrastructure, other competitors or bystanders. Distance: riders must complete the entire distance or as directed by race officials. Finish: a rider finishes when the leading edge of the front wheel crosses an imaginary vertical plane rising from the finish line drawn on the course surface. Course: a national level XCO course is 3.5km to 6km with a target lap time of 9 to 18 minutes, 99% rideable, with no more than 15% sealed or paved road. Target winning times: Elite and Expert 1:20 to 2:00; U23 1:15 to 1:30; Masters 1 to 4 1:15 to 1:30; Masters 5 to 7+ 1:00 to 1:15; Under 19 and Under 17 1:00 to 1:15; Under 15 0:45 to 1:00. The PCP may change the number of laps for weather. Environment: riders must ride only on the official course and leave no waste or litter.