Does anybody know how many CFM that these BDS 34x4 Mikuni carbs on our bikes put out. How about a simple formula to figure it out? pi*(bore/2)^2*stroke*number of cycinders*max rpm's/3456 = CFM needed or, pi x (2.99/2)^2 x 2.60 x 4 x 8500/3456 = 180CFM needed.