Jeez, Scrambled, don't post what ya don't know! The "CH" in "XLCH" had nothing to do with "chopped." The origin goes like this. In 1952, HD came out with their first unit construction motorcycle. It was a 45 c.i. sidevalver, designated the K. Variants included the KR (Harley's race machine until the 1972 rules change), KK (street bike with KR cam), and KH (55 c.i.)
The XL (Sportster) motor was simply an overhead valve top end on K cases. The "H" character was retained from the K series to designate 55 c.i. displacement. The original Sportster was the 1957 XLH, with battery ignition and touring tank and seat. The XLCH came later, with no battery (magneto ignition), smaller tank, and smaller seat. There was an open class in AMA Sportsman TT racing, and you'd see an XLCH entered from time to time.
Don't generalize about the "H" designator. In the big OHV V-twin models, it indicated a high compression motor. The 61 c.i. machine as was offered as the EL (low compression) or ELH and the 74 as FL (low compression) or FLH.