Motorcycle brass and rubber expansion well nuts for securing modified windshields and body panels

This kit of motorcycle fasteners is designed for riders and mechanics needing a reliable method to attach aftermarket components, specifically called out for use on modified windshields. The set contains 10 pieces of brass and rubber expansion well nuts, often referred to as rivet nuts or well nuts, across three common metric thread sizes: M4, M5, and M6. These fasteners work by being inserted into a pre-drilled hole; as the accompanying screw is tightened, the brass insert expands the rubber body, locking it securely in place against the panel. This creates a strong, threaded anchor point that is resistant to vibration, a common issue on motorcycles, without requiring access to the back of the panel for a traditional nut.

Features and Construction

The fasteners are identified by specific product codes that denote their size and thread: G388150 for the M4 version, G388151 for M5, and G388152 for M6. This allows for precise identification and ordering. Their construction is a two-material system designed for a specific mechanical function in vehicle modification.

Material and Build

Each fastener combines rubber and brass. The outer body is made from rubber, which compresses and expands to grip the sides of the mounting hole tightly. This rubber component also acts as a seal and damper, helping to minimise vibration transfer and potential rattling. Encased within this rubber is a brass nut. Brass is chosen for its corrosion resistance and durability, providing the strong, reusable threaded portion that the mounting screw engages with. The entire assembly is finished in a standard black colour, as noted in the product specifications.

Size and Practical Fit

The kit provides three distinct sizes to cover various fastening requirements. The G388150 variant is an M4 nut with an 11mm diameter. The G388151 is an M5 nut with a 12mm diameter. The G388152 is an M6 nut with dimensions of 13mm in diameter and 13.6mm in length. These dimensions dictate the size of the hole that needs to be drilled for proper installation. The pack contains 10 fasteners in total, offering a useful quantity for multiple mounting points on a single project, such as a full windscreen installation, though the exact mix of sizes within the 10-piece pack is not specified.

Uses and Placement

These well nuts are presented as hardware for motorcycle modification, with a stated purpose for windshields. Their utility, however, extends to any application on a bike or similar vehicle where a secure, blind fastener is needed.

Event or Professional Use

For professional mechanics or enthusiasts undertaking custom builds or repairs, this kit offers a standardized solution. The availability of multiple sizes in one pack means having the right fastener on hand for different components that may require different bolt sizes. They are suitable for securing fairings, windshields, instrument clusters, or small body panels where the back side is not accessible for a standard nut and washer. The riveting action provides a firm, permanent-feeling mount that withstands the rigours of road use.

Everyday Home Use

For the home garage mechanic, these nuts simplify the process of adding accessories. Installing a new windscreen, a dash panel, or even mounting a small accessory box becomes more straightforward, as there is no need to fabricate complex bracketing or struggle to hold a nut in an inaccessible space. The installation primarily requires drilling a clean hole to the correct diameter and then tightening the screw.

Benefits and Buying Value

The value of this product lies in its specific design for a common vehicular task and the practical advantages its two-material construction provides over simpler fastening methods.

Reuse and Low Maintenance

The brass thread core means the fastener can be unscrewed and re-tightened multiple times if adjustments are needed, unlike a plastic rivet which may break. The rubber body's grip generally remains effective through this process. The materials are chosen to withstand outdoor exposure and vibration without significant degradation under normal motorcycle conditions.

Why Choose This Product

This product addresses a clear need for vibration-resistant, blind fastening in motorcycle modification. The inclusion of three sizes (M4, M5, M6) in one pack increases its versatility, potentially covering multiple jobs from a single purchase. The 10-piece quantity provides enough fasteners for a complete installation with spares. It offers a hardware solution grounded in the practical mechanics of expansion and grip, rather than adhesive or temporary fixes.