Quote Originally Posted by BradMph View Post
Below for you Mikuni Carb Owners is the Sub-EGR valve. This valve refeeds exhaust back into the carb for reburning any possible left over fuels after it's first trip into motor.
That's a common misconception; the actual purpose and function of any EGR valve is to lower combustion temperatures by diluting the intake charge with inert (already-combusted) gases without affecting the fuel-oxygen ratio, thereby reducing NOx emissions formed at high combustion temps, which in turn lead to smog.