The 23-year-old Du Plooy crossed the line in 2:46:04 to take the 106km feature race title, closely followed by teammates Bernard Esterhuizen (2:46:07) and Nicol Carstens (2:46:10).
The new champion said they wanted to put the hammer down early, which was done as Esterhuizen, followed by Jack van Wyk, broke away within the first two kilometres.
“I managed to ride over to them and then Bernard and I got away from Jack and built a reasonable lead.
“Nicol joined us about 80km into the race and we were able to cross the line together.
“I felt our team read the race very well and they were kind enough to give me the victory at the finish. Equally, I would have given it to any of them because it was a really good team effort.”
Defending champion Anriette Schoeman took the women’s elite category for her 18th title in the 19-year history of the event. She finished in a time of 3:18:21.
The Africa Silks-Bestmed rider was happy to rack up another win but acknowledged that it “was a tough day at the office”.
“I lost the leading men early on and I always knew it was going to be a hard day,” said the Port Elizabeth rider. “It’s a tough route to start off with and obviously the conditions made it 10 times worse.”