Sydney ceremony before officers head off on their annual 280km motorbike ride to the nation's capital.
The families of Mr Cheng and Sgt Richardson will be joined by NSW Police Commissioner Andrew Scipione and NSW Deputy Premier Troy Grant at The Domain early on Saturday ahead of an annual commemorative ride to Canberra.
Mr Cheng, an accountant for the force for 17 years, was shot by a 15-year-old terrorist outside Parramatta police headquarters in October last year.
Five months later, Sgt Richardson, who had received three awards across his service, was killed in a late-night police chase in the Hunter Valley.
NSW police commissioner Andrew Scipione says he will ask the wives of police accountant Curtis Cheng and sergeant Geoffrey Richardson to write their husband's name on paper, which will be transported to the National Police Memorial in a special baton during the Wall to Wall ride of remembrance.
"This afternoon... We'll take those names out and well read them out and we will symbolically add them to the (police remembrance) wall," he said before riders left Sydney on Saturday.
The motorbike ride is in memory of the service and sacrifice of Australian police, as well as raising funds to help support their families.
More than 2000 police from across the country are expected to join the annual motorbike ride from Sydney to Canberra.
