1.1–1/8' Headset Expander — Compatible with carbon fiber forks and suspension forks that have steerer tubes with a 25.4–28.6 mm outer diameter. Designed to compress and align the headset reliably during installation. Key benefits Secure headset integration: Expands inside the steerer tube for even compression and accurate headset alignment during installation. Precision fit: Threaded adjustment lets you set the internal diameter from 22.9 mm to 25.4 mm so the expander seats correctly in a range of steerer tube thicknesses. Durable, lightweight construction: Aluminum alloy body with stainless steel components balances low weight and corrosion resistance for dependable performance in normal riding and maintenance. Simple to use with standard tools: Install and adjust using a single 6 mm wrench. Grease all parts except the sleeve before assembly for smooth operation and reliable torque. Features and specifications Model: 1.1–1/8' headset expander / compressor Steerer tube outer diameter compatibility: 25.4–28.6 mm Internal fit (adjustable): 22.9–25.4 mm Materials: Aluminum alloy main body; stainless steel hardware Tool required: 6 mm wrench Assembly note: Grease all parts except the sleeve before installation Practical use scenarios Fitting a sealed headset on a road bike with a carbon fiber fork: use the expander to align the headset stack and provide consistent compression without spinning the crown race. Servicing a suspension fork with a compatible steerer tube: hold the headset components centered while tightening the cap to achieve correct bearing preload. Workshop or home mechanic jobs: quick, repeatable setup for multiple headsets when replacing bearings, upgrading components, or performing routine maintenance. What makes this product stand out Exact, repeatable adjustment for a reliable fit across a range of steerer wall thicknesses. Combination of aluminum and stainless steel provides a lightweight tool that resists wear in everyday use. Straightforward installation process with common tools and clear greasing guidance to avoid binding or inconsistent torque. Included guidance Use a 6 mm wrench for tightening. Apply grease to all parts except the sleeve prior to assembly. Confirm steerer outer diameter is within 25.4–28.6 mm and set the internal diameter to match the steerer before inserting. This expander is intended for use with 1.1–1/8' headsets and compatible steerer tubes as specified above.