The shimano ultegra 6500 9 speed cassette is a high performance 9 speed cassette offering smooth and consistent shifts even when put under heavy pressure the two largest sprockets are mounted on a light weight alloy carrier to reduce weight and increase rigidity shimano ultegra 6500 9 speed cassette features high performance 9 speed cassette hyperglide sprockets have a computer designed tooth configuration with contoured shift gates resulting in a crisp smooth shift even under