Twelve people have been arrested on suspicion of dangerous driving after a memorial ride to commemorate two boys whose deaths sparked a riot.
The event happened on 10 June and involved large numbers of bikes and other vehicles travelling between Barry and Cardiff.
It came after the deaths of Kyrees Sullivan, 16, and Harvey Evans, 15, who were killed in a crash on 22 May.
Police said some of those involved put road users and pedestrians at risk.
South Wales Police said, 23 vehicles, including 11 quad bikes and two all-terrain vehicles, were seized from a unit in Wilson Road, Ely, Cardiff on 16 June.
Two men, aged 28 and 41, were previously arrested on suspicion of handling stolen goods and other offences, and were released on bail.
South Wales Police added that 11 people were to receive notices of intended prosecution (NIP) for alleged motor offences.
NIPs have been sent to three others to confirm who was using their vehicle at the time alleged offences were committed.
Kyrees and Harvey died when the e-bike they were riding crashed shortly after they were followed by South Wales Police officers.
This sparked riots in Ely that saw 15 officers hurt and 27 people arrested.
Force commissioner Alun Michael was criticised for claiming the teenagers had not been chased by officers after CCTV showed police following the pair.
Police subsequently admitted they had followed them after several doorbell cameras captured footage of the e-bike and police van.
Two police officers are under investigation for their conduct prior to the deaths of the boys.
The Independent Office for Police Conduct said gross misconduct notices had been served on the driver and passenger seen in the police van.
(Source: BBC)