Step by step guide; Replacing an A-head stem

There is some debate as to what this part should be called. In this guide, we refer to it as a stem or A-head stem, though the term “handlebar cam” is also often used.
We distinguish between stiff and adjustable A-head stems. Stiff stems are mainly found on road bikes and mountain bikes, where stiffness is usually of great importance,
while adjustable stems are often mounted on city bikes.