Chris king threadfit 24mm bottom bracketour threadfit 24 bottom brackets are designed and built to be durable serviceable and silent manufactured to create a precise and functional interface between your frames bottom bracket shell and your 24mm cranks our threadfit 24 bottom brackets ensure that your cranks will spin lightly and without interference to help with bike fit issues we have developed a range of conversion kits that allow our threadfit 24 to be used with a wide selection of ro