Organisers said Stuart Park was still boggy from recent heavy rains and unsuited to handling the 10,000 cyclists who will be taking part. 

Participants will begin wheeling their way from St Peters in Sydney to Dalton Park, Wollongong, between 6am and 8am on Sunday.

The lead riders are expected to arrive at the finish line between 8am and 8.30am.

The bulk of participants are expected between 10.30 am and midday.

With the change of finish line, trains taking the cyclists back to Sydney will leave from Fairy Meadow station rather than North Wollongong.

Special event trains will run from Fairy Meadow to Sydney between 11am and 4pm.

The Transport Management Centre has warned drivers to expect delays along the length of the course.

Southbound traffic on the Princes Highway from Sutherland to Waterfall will be heavy from 8am until midday as the speed limit through the area will be reduced from 100 to 60kmh. 

One southbound lane of the highway will also be closed from Heathcote to Waterfall between 5am and 1pm. 

Additionally, Lawrence Hargrave Drive will be closed to non-resident southbound motorists from Stanwell Tops to Stanwell Park between 6am and 3pm, while Point Street in Bulli between Hill and Blackall Streets will be closed eastbound from 6am to 3pm. 

Special event clearways will also be in place between St Peters and Fairy Meadow from 4am until 3pm.

Motorists should check signs before parking as vehicles left in these clearways will be towed away and a towing fee applies.