Technical info on KR and XLR:

 

 

1955 Set Up Sheet, as included in Double Valve Spring Kit # 18235-55R

 

1957 specifications and instruction manual, KR, KRTT, KHRTT:

page 1,  page 2,  page 3,  page 4,  page 5,  page 6,  page 7,  page 8,  page 9,  page 10

 

 

 

XLR Engine Specifications     1      2