BannedCR500Riders.com

its different from what ive seen before anyways. pulled the pipe from the 465 and seen there is no exhaust bridge, similar to the old hondas i guess. i pulled the reeds and found no bottom boost ports like the cr500, what i seen was 1 rectangular shaped port on the roof of the intake area. i wonder what the vintage suzuki, ktm, kawasaki and maico bikes motors looked like . you can kind of see it where the red line is

....same thing on the 1979 Honda CR250R cylinder. It's an additional transfer port fed directly from the intake tract rather than the crankcase. The 1979 is bridged, the 1978 is a single large combo port.