Update on my daulton sprocket. Recently did a full tear down of my motor and found the sprocket to be wearing somewhat quickly. I have a bit over 8,000 miles on it with a stock valve train reving to 10,500 rpm. That is indeed a raised ridge around the perimeter of the sprocket and the teeth are "swept back" a bit. Was hoping to get more out of it than that. Guess I'll give the koso a try. Really curious about the tension rail set up I've heard mentioned.