It's due to showers forecast this morning
The clerk of the course says there will be a minimum of a two-hour delay to today's racing schedule.
The decision has been taken due to showers forecast for this morning.
The Mountain Road had been due to close from 9am with the rest of the course shutting at 10am.
The Supersport 2 Race was due to take place at 10.45am following by Sidecar 2 at 2pm.
Organisers say a revised schedule will be issued in due course.
Forecaster at Ronaldsway Met Office, Kirsty Pendlebury, says they are expecting showers mid to late morning:
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