The Isle of Man Bank Town Centre Cycle Series has been cancelled.
Organisers say it is down to a lower than anticipated level of entries.
The inconvenience of road closures to local residents and businesses could not be justified with the numbers due to take part.
Castletown, Port Erin, Ramsey, Peel and Douglas were due to host races over the summer months.
All entry fees received will be returned in full within seven days.