Question: are all quill stems the same?
Answer: Quill stems are found on many older bikes as well as some inexpensive bikes. ... Quill stems come in different steerer tube and handlebar sizes. It is wise to measure your components to ensure that you are installing or ordering the correct stem. The most common handlebar diameters are 22.2, 25.4, 26.0, 31.8 and 35.0mm.