KAYAKING/ ROWING: Australia's Olympic kayaking champions are out to prove to their rowing compatriots they are the country's fastest men on water.

London Games gold medallists Tate Smith, David Smith, Murray Stewart and Jacob Clear will take to Melbourne's Yarra River on Tuesday to race rowing's 2012 silver medallists Josh Dunkley-Smith and Will Lockwood with Spencer Turin and Alex Lloyd.

Six-time Olympic rower James Tomkins will officially start the 500 metre sprint - dubbed the Battle of the Fours - commentated by former Oarsome Foursome teammate Nick Green.

"We issued the challenge a couple of months back, and now they've stepped up to the mark," kayaker Stewart told AAP on Wednesday.

"There was a bit of banter going between the rowers and ourselves - I'm not sure who instigated it, it might've been one of the guys in our crew actually.

"They've since been very quiet about the whole process, so hopefully that doesn't mean that they're overly confident."

Stewart admitted the contest will be tight, with his K4 team's acceleration off the mark negated by the M4's back-end speed.

"It's going to be interesting," he said.

"I think the odds are probably against us, but we'll give it a crack anyway.

"The rowers tend to have a higher profile within Australian sport than the canoeists.

"To get one up on the rowers, there'll definitely be bragging rights for a while."

David Smith, Tate, Stewart and Clear beat defending champions Hungary in the men's K4 1000m to win gold at London last year, while the M4 claimed silver behind Great Britain in the rowing regatta.

AAP