In general, the opening and closing strength of folding knives is not adjustable. The strength required to open and close a folding knife is typically determined by the design and mechanism of the knife. The opening mechanism of a folding knife, such as a thumb stud, flipper tab, or thumb hole, is designed to provide a specific level of resistance in order to ensure safe and controlled deployment. Similarly, the closing mechanism, such as a liner lock, frame lock, or lockback, is engineered to provide a secure and reliable locking mechanism.However, its worth noting that the action of a folding knife may become smoother and easier with use as the pivot points wear in and any lubrication applied to the knife may also affect its ease of opening and closing. It is advisable to follow the manufacturers guidelines on maintenance and lubrication to ensure the knife operates optimally.If you find a folding knife to be too difficult or too easy to open or close, it is recommended to choose a different knife that suits your preferences or seek out a different model with a different opening or closing mechanism.