LUNJE adjustable bike stem 31.8mm, Matte Black 145mm, 6061-T6 aluminum, 120° adjustable angle

The LUNJE Adjustable Bike Stem 31.8mm is a lightweight, 6061-T6 aluminum handlebar stem that lets you change reach and angle up to 120° across four lengths for better control and comfort on mountain, road, and city bikes.

This adjustable stem gives riders one component to tune posture and handling without swapping bars or forks. Engineered around a 31.8mm handlebar clamp and a 28.6mm (1-1/8") steerer interface, the LUNJE stem balances durability and weight for everyday commuting, long road miles, or trail use. Available in 90, 110, 130, and 145mm lengths, it offers a broad fit range so you can dial in steering behavior and body position quickly and securely.

How does changing stem length and angle affect handling?

Altering stem length shifts your weight distribution and steering leverage. Shorter stems quicken steering response and boost maneuverability on technical trails, while longer stems straighten the steering arc and increase stability at speed. The adjustable angle lets you fine-tune back and wrist posture without changing saddles or bars.

• Shorter (90mm): faster steering, nimble cornering.
• Medium (110–130mm): balanced control for mixed terrain.
• Long (145mm): improved straight-line stability at higher speeds.
• 120° angular adjustment: customize upright vs. aggressive reach.

Will this stem fit my bike and handlebars?

The LUNJE stem is made to accept 31.8mm handlebars and fits standard 28.6mm (1-1/8") steerer tubes, so it covers most modern MTBs, gravel and many road bikes. Confirm your handlebar clamp diameter and steerer tube size before ordering. Use the supplied clamp hardware and torque to the manufacturer’s recommendations for safe installation.

• Handlebar clamp: 31.8mm standard size.
• Steerer fit: 28.6mm (1-1/8") steerers.
• Four length choices: 90, 110, 130, 145mm to match reach needs.
• Hardware included for secure mounting; torque spec recommended.

What materials and build features ensure durability?

Constructed from 6061-T6 aluminum, this stem offers a strong-to-weight ratio suited to off-road impacts and daily road use. The finish is corrosion-resistant and machining keeps clamp contact precise to prevent slippage. The design also distributes force to reduce localized stress on the bars and steerer.

• 6061-T6 aluminum body for toughness and light weight.
• Precision-milled clamp surfaces for secure grip without damage.
• Corrosion-resistant finish for longevity in varied conditions.
• Anti-slip grip design to reduce handlebar rotation under load.

How simple is installation and angle adjustment?

Installation is straightforward for anyone comfortable with basic bike mechanics: loosen the faceplate and steerer bolts, set desired length and angle, then re-tighten to spec. Angle adjustment is tool-based and stable under riding loads, so once tightened the position remains reliable. If you switch between bikes, the universal clamp sizes make transfer quick.

• Tool-required setup—standard hex wrenches handle the job.
• Angle adjustable up to 120° for posture dialing.
• Stable clamp design prevents slippage after torqueing bolts.
• Compatible across many bike types for easy swaps.

Who is this for: Cyclists who want one stem to cover multiple riding styles — mountain bikers seeking sharper handling, commuters wanting a more upright stance, or road riders looking for a tailored reach. Choose the length that matches your frame and riding goals, and use the angle adjustment to refine comfort and control without replacing multiple parts.