Moin Jungs,
ich hab da 'ne andere Übersetzung gefunden, die H ist höher verdichtet! So wie Defcon schon schrieb...
Sportsters: Models beginning with X are Sportsters. These descend from the K series, 1952-56. The XL series started in 1957. They are "unit construction" (engine & transmission share a common case). X was in the normal series, following the U and V used for flathead Big Twins. L stood for high compression (7.5:1 in 1957). In 1958 came the XLH with H meaning Higher-power or High-compression (9:1) or Hot
Gruss
Widder