You can use this method with any part of the chicken, but it does work best with the bone in on the dark meat. If you do BBQ the chicken breasts you have to be very careful they don't dry out, so keep the breasts on the coolest part of the BBQ. Add your own sauce just before the meat is cooked. I marinated my meat over night in a home made sauce which really lends extra flavour to the chicken.
Wash the chicken and pat dry. Put in a large container over night to marinate. I added a little liquid smoke to my marinade.
Next day remove the chicken and grill over high heat. When you get some decent grill marks on the meat flip it and do the same on the other side. Then, turn the BBQ down to low and let the chicken grill until just about done. That should take about 20-30 minutes. Cover and cook for about 30 mts. It depends on your grill, check it with the thermometer every so often to see how it's doing. The meat should be around 170'F when completely done.
Slather with the BBQ sauce, grill a little longer. Remove the chicken and let sit for at least 10 minutes under a tin foil sheet.