The pivot arm initially positions {HEAD ~ the tire} on {TAIL ~ the wheel} such that the wheel partially protrudes through the center aperture of the tire 
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The pivot arm initially positions { HEAD ~ the tire } on { TAIL ~ the wheel } such that the wheel partially protrudes through the center aperture of the tire
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH