Officers would like to speak to the riders who were seen between First Tower and West Park at about 9pm on Sunday.
One of the bikes is described as white and both are said to have had ‘noticeably loud exhausts’.
The bikes were seen travelling in convoy, with a ‘distinctive bright orange car’ and were last seen travelling towards Cheapside, the force said.
Anyone who saw the vehicles, or has any information, is urged to contact the States police on 612612 or call Crimestoppers on 0800555111.
