Thread lockers are chemical products used to stabilize threaded connections, i.e., mechanical joints made using screws, bolts, and threaded seats. The underlying principle of a threaded connection is the friction generated between the thread surfaces. When friction is low, for example due to thread wear or the presence of dirt or oil, vibrations and impacts—stresses typical of track use—can cause gradual loosening, which can result in the two components losing their grip. This can result in a simple return to the pits or, in the worst cases, a potentially dangerous situation on the track. The purpose of the thread locker is therefore to prevent the connection from loosening, but also to seal the thread against moisture and dirt. These products are available in different strength levels, i.e., the level of force required to unscrew the connection after the product has hardened. To help you choose, a distinction is made by color: purple (low resistance), blue (medium), green (medium-high) and red (high). Purple thread locker is formulated for connections requiring a light, easily reversible hold. It prevents loosening due to vibration, yet allows for disassembly with standard tools, without risking thread damage. It is suitable for small screws and bolts or those made of delicate materials such as aluminum or ergal. To use thread locker correctly (regardless of its "color"), simply apply a drop directly to the thread, after ensuring both the hole and the screw are clean and dry. The screw should then be tightened immediately into its seat, before the product dries and polymerizes, locking the screw. In karting, purple thread locker is used, for example, to secure the sprocket carrier, pinion, or throttle cable clamp—points subject to vibration but requiring adjustment. However, it is not recommended for frequently disassembled parts, such as bumpers, seats, or wheel nuts, for which mechanical solutions such as self-locking nuts are more suitable. Finally, it cannot be used on couplings with plastic parts, as they could be damaged or chemically altered. The product we recommend for this product category is Loctite 222, available in a 10 ml container.

Editor's Note
The color-coded classification of threadlockers (purple, blue, green, red) is a commercial classification adopted by many manufacturers, but it does not correspond to a recognized technical standard. The final strength of the product and its specific properties may therefore differ between different brands.

Editor's Note 2
Red thread locker, due to its high strength, is very difficult to remove (preheating to at least 250°C is required), and for this reason, it is generally not used in karting, where frequent disassembly is required, even for engine components.

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