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the Evo air cleaner was good for about 140 CFM....the twin cam probably about the same ( excepting the 14).
Our pals at hot bike did some great air cleaner comparos back then, and a carb with no air cleaner was only able to pull about 110 CFM without an air cleaner to order the air.
a cupped hand held at the carb throat came in at about 125 CFM...the Hype at about 155CFM and the S/E and Ness about 260 CFM.
Winner was the Zipper's velocity stack at just under 400.
the last 3 having more flow potential than the motor.
mike
Good to see actual measured data. This pretty much tells the story.
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