Judging from the photos of that bike it looks like it has more street oriented gearing so you may not have to make any changes. The JTR279 rear sprocket configuration is what fit's all 3 of the Chinese bikes I've owned.
http://www.jtsprockets.com/catalogue/sprocket/JTR279
That's for a 520 chain but JT sprockets also makes them for a 428 chain.
The Honda CG clone engines I have all use the JTF1264 front sprocket for 428 chain.
http://www.jtsprockets.com/catalogue/sprocket/JTF1264