airmailrpl (asker) Dec 19, 2008:

Many Thanks ......................................... .... Many thanks to paya2008 for the above reference

airmailrpl (asker) Dec 19, 2008:

I believe these are Tread Lugs.................. Tread lug
Tread lugs provide the contact surface necessary to provide traction. As the tread lug enters the road contact area, or footprint, it is compressed. As it rotates through the footprint it is deformed circumferentially. As it exits the footprint, it recovers to its original shape. During the deformation and recovery cycle the tire exerts variable forces into the vehicle.[citation needed] These forces are described as Force Variation
http://en.wikipedia.org/wiki/Tire#Tread_lug

airmailrpl (asker) Dec 18, 2008:

already have Ombros => shoulders... unfortunately there are already Ombros => shoulders...in the text..

• Incrementou com um reforço de borracha na região dos ombros (cordões ou filetes de borracha na região do flanco que protege durante às agressões ou contatos com guias ou meio fio);

anybody got a good word for "tratividade ??? "