Police said the concrete truck was travelling along Beleura Hill Road when it struck a cyclist riding in the opposite direction about 6.45am on Friday.

Local business owners have suggested wet weather may have played a role in the accident, which occurred on a residential street which does not have a designated cycling lane.

The cyclist, a 34-year-old Mount Eliza man, was knocked from his bike.

He suffered severe head and facial injuries and was flown by police helicopter to The Alfred hospital, where he remained in the intensive care unit in a critical condition at 10am.

Mechanic Steve Kovacs saw emergency services at the scene as he made his way to work at nearby Beleura Hill Motors.

He said the Mornington area was popular among cyclists, although there were few designated bike paths.

"There's not proper bike tracks so I guess [they are] cycling on the side of the road," he said.

George Xiu, who owns a milkbar on Beleura Hill Road, said the road was not usually busy, but the weather had been wet and gusty early on Friday morning. He said it was a residential street with only a handful of shops and no traffic lights.

The 57-year-old male truck driver, from Woodleigh Vale, is assisting police with their inquiries.

Mornington Peninsula Shire Mayor Bev Colomb said her thoughts were with both men involved in the accident.

"Road safety is the responsibility of all road users, and that means both cyclists and drivers have to be extra vigilant," she said.

Beleura Hill Road was closed for some time between Barkly and Shandon streets as police examined the scene.

The incident comes as more than 1000 bike riders prepare to take part in a special memorial ride for cyclist Alberto Paulon, who was killed in a "dooring" accident on Sydney Road on Friday last week.

The event, dubbed #AlbisRide, will start at 5.30pm on Friday near the southern end of Sydney Road in the parklands on Royal Parade, and will end at Moreland train station car park, near Gandolfo Gardens.

Anyone who may have witnessed the incident at Mornington is asked to contact Crime Stoppers on 1800 333 000.