Heavy duty radial tire with chafer height greater than bead apex height

摘要

A heavy duty radial tire comprises: a carcass ply turned up around a bead core in each bead portion from the inside to outside of the tire so as to form a pair of turnup portions and a main portion therebetween; a bead apex rubber disposed between each of the turnup portions and the main portion, each. of the turnup portions extending radially outwardly beyond a radially outer end of the bead apex to adjoin the main portion; a chafer rubber disposed along at least an axially outer surface of each of the bead portions so as to define at least a flange-contacting part for contacting with a flange of a wheel rim; the height of the radially outer end of the bead apex being in the range of from 7 to 35% of the height of the carcass at the tire equator and being less than the height of the radially outer end of the chafer rubber; and the flange-contacting part being devoid of a concave profile. When the carcass ply is made of steel cords whose sectional area is in the range of from 0.10 to 0.25 sq.mm, a carcass reinforcing layer is disposed along the carcass so as to extend at least between the maximum tire width points and the edges of a belt disposed radially outside the carcass in the tread portion.