It was his second successive win in the series and he held off a strong field to claim the 70km title.
“Today was great fun, a really good route with incredible trails. It was just so nice out there after the rain,” said Heyns.
In the women’s race Candice Neethling of Team Dorma took the lead on the first big climb, which came after 20km of racing.
From the summit she steadily increased her lead which put her in 22nd place overall.
Carmen Buchacher of Velocity Sports Lab finished second, with Katie Lennard rounding out the podium positions.
“On the first big climb I knew what kind of pace I could hold to the top, so I kept that and built a decent lead over Carmen,” said Neethling.
“From there, I just had to make sure that she wasn’t closing on me. Fortunately there was a lot of technical riding, which gave me an advantage and I extended my lead.”
In the 40km event, Robert Hobson and Allison Morton won the men’s and women’s races.
The third round will be the Hemel & Aarde event near Hermanus on October 8.
View more results here.