H&H Stem Catch Mount for Brompton Bicycle G Line

The G-Line Stem Catch Mount is an upgraded folding-position stabilizer specifically designed for Brompton G Linemodels. It secures the head tube firmly in the folded position, preventing outward protrusion that can affect portability and storage.

Compared to the original plastic stopper—which may deform over time—this upgraded mount features a CNC-machined aluminum body, two adjustable spacers, and a titanium bolt for long-term durability and precise fitment. The adjustable design allows fine-tuning of the mounting position for a tighter, cleaner, and more compact fold.

Testing shows a reduction of approximately 20 mm in total folded width, significantly improving storage efficiency while enhancing the overall appearance of the bike.