An object of the present invention is to provide a pneumatic tire capable of significantly increasing the possibility that the tire can be recycled as a base tire for a retreaded tire without so much sacrificing a product life of the tire prior to retreading. Specifically, the present inventions provides a pneumatic tire 1 having a tread portion 2, plural tread grooves including a first tread groove 5 and a second tread groove 15 formed in the tread portion, and a first bottom-up portion 10 with a top surface 10a as a tread wear indicator, the first bottom-up portion being provided at a groove bottom 5b of the first tread groove 5 such that a distance measured in the tire radial direction from an opening end position 5a of the first tread groove to the top surface 10a is x1, comprising: a second bottom-up portion 20 with a top surface 20a as a retread indicator, the second bottom-up portion being provided at a groove bottom 15b of the second tread groove 15 formed in the central region 3 of the tread portion 2 such that a distance measured in the tire radial direction from an opening end position 15a of the second tread groove to the top surface 20a is x2 shorter than said x1.

A tire includes a circumferential tread having a tread element disposed thereon, wherein the tread element includes a top surface that defines a first plane. The tire further includes at least one substantially helicoid-shaped sipe disposed in the tread element. The substantially helicoid-shaped sipe is defined by an opening in the top surface extending in a first direction in the first plane when the tire is new, and is further defined by a base extending in a second direction in a second plane parallel to the first plane. The second direction is disposed at an angle between 45 and 135 with respect to the first direction.

A tread wear indicator for a tire is provided. The tire includes a pair of sidewalls and a tread and the tread includes a plurality of circumferential grooves and a plurality of lateral grooves. The tread wear indicator is formed in a selected one of the lateral grooves adjacent a selected one of the circumferential grooves. The indicator includes a plurality of step elements descending from a radially outward surface of the tread toward the base of the selected one of the lateral grooves. Each step element includes an axially-extending surface that is approximately parallel to and is radially inward of the radially outward surface of the selected one of the tread elements, and a radially-extending surface that extends approximately perpendicular to the axially-extending surface. The axially-extending surface of each step element is formed with indicia visible to a user of the tire.

Tire for a civil engineering vehicle comprising a tread of high initial thickness E, this thickness corresponding to the thickness of material which can be worn during use, this tread comprising a smooth rolling surface, i.e. without any recesses, intended to come into contact with the ground during rolling, this tread being limited axially by lateral faces, these lateral faces being extended radially on the tire by sidewalls, this tread being provided with a wear indicator device to visually indicate a wear level of the said tread, this tire being such that the wear indicator device comprises, in combination, a plurality of grooves formed on at least one of the lateral faces of the tread and, for each groove, a visual index indicating a wear level corresponding to the percentage of the initial thickness E remaining to be worn.

A regroovable tread profile of a pneumatic vehicle tire includes a regrooving indicator formed with an additional indent in the base of the depression in the form of a blind hole lying transversely in relation to the main direction of extent (U) of the groove and having a length of extent (A.sub.2) and an indent depth (B), where (B) is formed such that B<A.sub.2 and B<A.sub.1 and B<L and with a depth of extent (T.sub.2) where T.sub.2>T.sub.1, which is measured starting from the groove base inward in the radial direction (R) to the base bounding the indent radially inwardly. The depth of extent (T.sub.1) forms the measure for the minimum regrooving depth and the depth of extent (T.sub.2) forms the measure for the maximum regrooving depth.

An autonomous, plug-in and sacrificial wear sensing system including at least one wearable sensor, autonomous energy supply and means for remote radio-frequency communication. The system includes a tubular tread wear indicator body embedded within a tire tread element. The indicator body is centered within the tread element and is shaped in the form of a tube. The sensor element operably changes in at least one electromagnetically measurable physical parameter as the tread element wears radially inward. The system provides a full tread wear system including the algorithm for signal and data processing, buffering and decision making routines to remotely provide vehicle driver or owner with current tire wear status, tire typevehicleseason match and with real-time estimation of remaining tire life.