 In the 2002 model year , Klein replaced 6061 aluminium alloy with a new alloy called ZR 9000 , that used zirconium in place of chromium ; the new alloy had not been assigned an industry number and it was named after the unused 9000 series . Advertised improvements included a 190 grams ( 6 @.@ 7 oz ) decrease in weight per frame and a fatigue life five times longer than the 2001 model year frames . 
