| S&S type 'E' or 'G' carb facts Stock 'E' butterfly: 1.8750 dia. or 47.6MM Stock 'E' venturi: 1.5625 dia. or 39.6MM Stock 'G' butterfly: 2.0625 dia. or 52.3MM Stock 'G' venturi: 1.7500 dia. or 44.4MM Motorcycle carbs are determined by venturi size rather than by the automotive standard of CFM (cubic feet per minute) 'E' carbs can be used generally on engines up to 100ci 'G' carbs are recommended for engines 90ci and up An 'E' carb with it's smaller venturi will flow less air but at a faster speed for quicker low end response. A 'G' carb will flow more air at the top end but because of the larger venturi air flow is slower in the low and mid range. To use a 'G' carb on smaller engines is sometimes a trade off between performance and good response. A 'G' carb on a smaller engine can benefit by installing the 'xXx Booster Kit'. Low speed throttle response is improved because the booster forces more of the available air through itself at lower air speeds. Now more top end power becomes available due to being able to use a larger carburetor. |