The pivot arm is then advanced toward the mounting table so that the sector of the tire beads contacts {HEAD ~ the radial perimeter surface} that is defined between {TAIL ~ the flanges} of the wheel  
The pivot arm is then advanced toward the mounting table so that the sector of the tire beads contacts { HEAD ~ the radial perimeter surface } that is defined between { TAIL ~ the flanges } of the wheel
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH