The Olympic rowing programme was postponed on Thursday for 24 hours due to thunder and lightning in the area, organisers said.
The races will now be held on Friday, starting at 2:10pm (0610 GMT). Friday had been planned as a rest day. The Olympic finals will be held on Saturday and Sunday.
Ireland's heavyweight four will race in Friday's 'B' final after finishing sixth in their high quality semi-final race at the Shunyi Rowing-Canoeing Park.
Ireland's lightweight four crew will race in the Olympic semi-final, hoping to go one better than their heavyweight counterparts and qualify for an Olympic final at Shunyi.
