RLMVGBX 1 Pair Bike Handlebar Stem Shim 25.4mm to 31.8mm

• Lightweight Corrosion-Resistant Aluminium Build Crafted from high-grade aluminium alloy, these handlebar shims add negligible extra weight to your bike setup. The material offers excellent rust and corrosion resistance, maintaining reliable performance and appearance through regular outdoor riding and variable weather conditions.
• Textured Anti-Slip Surface for Secure Hold The wavy ribbed surface design increases friction between the shim, handlebar and stem for a tighter, more secure fit. It prevents unwanted handlebar slippage during riding to improve control and safety, while smooth contact edges will not scratch or damage handlebar or stem surfaces.
• Precision CNC Machined Anodised Finish Manufactured with accurate CNC cutting, the shims have smooth, clean edges and consistent dimensional tolerance for a snug, even fit. The black anodised surface delivers a sleek, polished appearance with good fade resistance, upgrading the look of your cockpit alongside functional performance.
• Quick Straightforward Installation No specialist tools are required for fitting. Simply place the two shims inside the stem clamp, position your 25.4mm handlebar, then tighten the stem bolts as normal. The open C-shape design makes installation and removal fast and simple for at-home bike maintenance and upgrades.
• Accurate Size Conversion for Stem Upgrades These shims enable you to fit 25.4mm diameter handlebars into a 31.8mm stem clamp. They are a practical, low-cost solution for handlebar swaps, component upgrades and custom bike builds, compatible with most mountain bikes, road bikes and commuter bicycles.

The RLMVGBX handlebar stem shim set is a practical bicycle component designed to resolve diameter mismatch between handlebars and stems. Made from durable lightweight aluminium alloy with an anti-slip textured surface and precision CNC machining, it enables 25.4mm handlebars to be fitted to 31.8mm stems reliably. This pair of shims is ideal for DIY bike upgrades, handlebar swaps and general cycling maintenance. Full Product Specifications Quantity: 1 pair (2 shims) Core material: Aluminium alloy Conversion size: 25.4mm handlebar to 31.8mm stem Surface treatment: Black anodised finish Product dimensions: 11 × 6.9 × 2.3 cm Unit weight: 20g Design: Open C-shape with ribbed anti-slip inner surface Material & Performance Benefits Aluminium alloy construction delivers high strength at very low weight, so it does not add unnecessary bulk to your handlebar setup. The anodised coating protects against corrosion, scratches and fading, suitable for year-round outdoor riding. The internal wavy texture boosts static friction between the shim and handlebar, preventing rotational slippage under steering load for safer, more predictable handling. Precision CNC production ensures consistent wall thickness and accurate diameter matching for even load distribution across the stem clamp. Step-by-Step Installation Guide Loosen the stem clamp bolts fully and open the stem clamp carefully. Place one shim on each side of the inside of the stem clamp, with the textured surface facing inwards. Insert your 25.4mm diameter handlebar into the stem and adjust to your preferred angle and position. Tighten the stem bolts evenly and gradually to the manufacturer’s recommended torque setting. Check the handlebar is securely held before riding. Suitable Applications Mountain bike, road bike and commuter bike handlebar upgrades Swapping between different diameter handlebars on an existing stem Custom bike builds and component compatibility adjustments Home workshop bicycle maintenance and modification projects Package Contents 1 pair (2 pieces) × Aluminium Bicycle Handlebar Stem Shims (25.4mm to 31.8mm) Important Notes Please confirm your handlebar diameter is 25.4mm and your stem inner diameter is 31.8mm before purchase to ensure correct fit. Always tighten stem bolts evenly to the correct torque; do not over-tighten to avoid component damage. Inspect stem tightness periodically before riding to maintain safe handling. This product is a bicycle fitting accessory intended for adult cycling use only.