Heavy duty tire

A heavy duty tire comprising a tread formed from a rubber composition comprising:

• a rubber component including a styrene butadiene rubber;
• and
• a filler including silica,
• wherein the tread has a tread surface configured to come into contact with a road surface,
• the tread has a plurality of circumferential main grooves extending continuously in a circumferential direction,
• the plurality of circumferential main grooves include a crown circumferential main groove located on an equator plane and a pair of shoulder circumferential main grooves located on outermost sides in an axial direction,
• the plurality of circumferential main grooves define a plurality of land portions in the tread,
• the plurality of land portions include a pair of crown land portions closest to the equator plane and a pair of shoulder land portions including ends of the tread surface,
• each of the crown land portions has a crown narrow groove extending continuously in the circumferential direction,
• the crown narrow groove defines two crown narrow land portions in the crown land portion,
• each of the crown narrow land portions has crown sipes traversing the crown narrow land portion,
• the crown narrow groove includes a body portion main body and an enlarged width portion located radially inward of the body portion main body,
• opposing wall surfaces of the body portion main body are brought into contact with each other by deformation of the tread,
• a groove width of the enlarged width portion is wider than a groove width of the body portion main body,
• the enlarged width portion includes an inflection portion and a bottom portion,
• the bottom portion is located radially inward of the inflection portion,
• a contour of the inflection portion is represented by an arc,
• a contour of the bottom portion is represented by an arc,
• a radius Rc of the arc representing the contour of the inflection portion is larger than a radius Rt of the arc representing the contour of the bottom portion,
• a groove depth DGs of each crown sipe is shallower than a groove depth DGg of the crown narrow groove,
• an amount CSB of the styrene butadiene rubber in 100 parts by mass of the rubber component is not less than 10 parts by mass,
• an amount BS of the silica per 100 parts by mass of the rubber component is not less than 15 parts by mass, and
• the amount CSB of the styrene butadiene rubber, the amount BS of the silica, the groove depth DGs (mm) of each crown sipe, and the groove depth DGg (mm) of the crown narrow groove satisfy the following relational expression:
• (
• CSB
• +
• BS
• )
• /
• (
• DGg
• -
• DGs
• )
• ≥
• 5.