So my in-laws asked if I would do a rib roast for Christmas if they bought it. I said sure, I'll put it on the rotisserie like i normally do. My mother in law just showed up with a 16 pound 18 inch roast. I'm not afraid yet, I just think this thing will bend my spit down and bog my motor. The oven is out of the question as I want to do this outdoors. I have my Weber genesis Silver grill with a rotis or I can mount my big rotis on my Chargriller and remove my tuning tiles. Has anyone rotised a side of meat this big? I normally cut back the fat cap, season and re-tie a three or four bone roast but this is long and the bones taper down which alarms me to un-even cooking. I'm thinking to do it in my char griller with a strong fire on the bony end and a mild fire on the meaty end. I've always rotissed my rib roasts with two fires so that is not new to me, I was just concerned about getting it just below med rare the whole way across.. Any input?