What is Solid Shock
A significant indication of the cushioning ability of any polyurethane-filled or solid tire lies in the durometer, or hardness of the rubber compound and other components in the case of solids and the polyurethane material that fills the cavity in the case of the filled pneumatic tire. A solid or polyurethane-filled tire with high durometer components is harder and absorbs less impact. A tire with low durometer components is softer and absorbs more impact.
Most solid rubber tires are manufactured with a two or three stage construction. They typically have a tread durometer of 65 and higher, with inner layers at higher durometer levels. Many solid tires have added aperture holes in an effort to try and reduce the negative impact of a harsh ride performance.