Sissis started racing junior motocross before joining the Sidewinders Under 16 Speedway Club in the northern suburbs of Adelaide at just 9 years of age.

Sissis then chased his Grand Prix dream and went on to ride in the 2010 Red Bull MotoGP Rookie Cup.

After qualifying 9th for the first race at the Losail International Circuit in Qatar, Sissis got a good start and was 2nd on the first lap before slowly dropping back and eventually finishing 7th.

The high point in Sissis' racing career to date was his third-place finish at his home Grand Prix at Phillip Island on 28 October 2012.

In December 2014, Sissis decided on a return to speedway, signing to ride in 2015 for Sheffield Tigers in the British Premier League.