In Zhuhai there is a track called the Golden Apple Kart Track on QiAo island, it's 10 minutes from the Zhuhai International Circuit.

It's quite a small track, but good for small bikes 250cc and under. There were guys who take out 600cc bikes, but it's better suited for smaller bikes.

The rates are cheap, 150rmb per day, or if you want to sign up for a year, it's 1500rmb and you can ride whenever you want, as long as they don't have any karts going out.

If you have access to youtube, you can do a search and probably find some onboard videos from the track.