Warrnambool's Viaduct Road will be closed to traffic on Sunday for a series of criterium races from 7am to 2pm as part of a new event attached to Saturday's Powercor Melbourne to Warrnambool Cycling Classic.

The roundabout at the Stanley Street and Viaduct Road-Pertobe Road intersection will be managed by traffic controllers, and vehicles will be allowed through this intersection between the different cycling events.

Race committee member Shane Wilson said the Warrnambool community had always provided fantastic support to the event.

"As a committee we are really appreciative of the courtesy the Warrnambool community shows," he said.

"The Melbourne to Warrnambool cycling festival is important to our district and it is important cyclists and drivers show courtesy to each other."

Free parking is being provided for spectators at the Shipwreck Bay Holiday Park who can then make the short walk or ride to the festival site near the Pavilion Cafe on Sunday.

"It will be best to avoid driving through the (Stanley Street and Viaduct Road-Pertobe Road) intersection during the day," Mr Wilson said.

"The elite criterium race will be an outstanding spectacle with 87 riders travelling along Viaduct Road at high speeds.

"If we can get everyone down to the Pavilion Cafe by foot or by bike it will make this a fantastic cycling festival."

On Saturday the west bound lane of Raglan Parade will be closed between Banyan Street and Liebig Street from 7.30am to 5.30pm with diversions along the east bound lane.

The Raglan Parade closure will be extended from Flaxman Street to Kepler Street between 11am and 4.30pm on Saturday for the finish of the Port Campbell to Warrnambool race, the community ride and the finish of the Melbourne to Warrnambool event.

"The community ride will run along the south side of Raglan Parade, along the 1.2 kilometres from Fletcher Jones to the finish line," Mr Wilson said.

Drivers will be able to cross Raglan Parade at the managed vehicle access points at Kelp Street, Japan Street and Foster Street during this period.

Victoria Police will be managing a rolling road closure along the Melbourne to Warrnambool race route.

Although roads along the route will remain open, drivers may incur a short delay whilst the race passes.

"If people are heading down the Great Ocean Road they should look at alternatives to drive home, or stay for an extra coffee in Port Campbell," Mr Wilson said.

"The race is likely to hit Port Campbell around 12.30pm and will turn right, coming from Timboon, onto the Great Ocean Road rather then heading into Port Campbell."

Cyclists in the Port Campbell to Warrnambool Handicap will need to obey all road rules, as there is no police closure during the race. Drivers should be mindful when passing cyclists and only do so when it is safe. Event signage will be placed along the route.

"We can't have a rolling road closure during a handicap race," Mr Wilson said.

"Cyclists will need to obey the road laws, and drivers should be aware there are racing cyclists on the road and drive appropriately."

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