THINstem – Folding Bike Stem

Save Space. Prevent Theft. Store Anywhere.

THINstem is a patented quick-release stem that lets you rotate your handlebars 90° in seconds—no tools needed. It instantly makes your bike over 60% narrower, perfect for tight spaces like hallways, elevators, condos, and car racks.

Made from lightweight, heat-treated aluminum, THINstem replaces your existing stem and fits most bikes and e-bikes.

Fits Most Handlebar Sizes

THINstem fits both 31.8mm (Oversize) and 25.4mm (1") handlebars—a shim is included with every unit for a secure fit.

Tip: Handlebar size is measured at the center of the bar where it clamps into the stem.

How It Works

Flip the lever, unblock the safety tabs, and rotate your handlebars inline with the frame. It’s fast, secure, and tool-free.

Built-in Safety Features

• Three secure locking points: Centering Tab, Lever Clamp, and Stop Cap
• V4 design includes safety tabs for extra security
• Strong, lightweight aluminum construction

Size Options

Recommended Accessories

• Folding Pedals – For an even slimmer bike profile

Note: You’ll need good hand strength to fully close the quick-release lever for safe use.