Pneumatic tire having a dual layer tread

A pneumatic tire comprising a carcass (10) und a tread (11) located radially outward of the carcass (10) and extending between tire sidewalls is disclosed. The tread (11) provides a tread running surface (7). The tread (11) comprises a first, radially outer tread layer (12) comprising a first rubber compound and a second, radially inner tread layer (13) comprising a second rubber compound. The second tread layer (13) is located radially adjacent to the first tread layer (12). The first rubber compound is different from the second rubber compound. The second tread layer (13) comprises a plurality of integrally formed extensions (14) of the second tread layer (13) and hence of the same rubber compound than teh second tread layer and said extensions extending from the second tread layer (13) radially outwardly to the tread running surface (7). The first rubber compound and the second rubber compound each comprise at least at least 30 parts per hundred parts of rubber (phr) of silica. Each of the extensions (14) has a width as measured in the axial direction of the tire (1) in a range of from 1 to 15 mm.