The rider was performing on busy Cavill Avenue, Surfers Paradise, just before 5.20pm on Thursday as part of warm-up events for this weekend’s Gold Coast 500.
Footage of the incident obtained by 9News shows the rider landing awkwardly after performing a backflip and riding diagonally off the ramp and into a barrier.
That barrier then hit several bystanders.
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Paramedics said four people were injured but only two, believed to be a man and a female, were taken to the Gold Coast University Hospital in a stable condition.
It was unclear what their injuries were or whether the rider was among the patients.
Organisers are yet to comment on the incident.
