{HEAD ~ The eccentrics} and cranks associated with {TAIL ~ each piston} and cylinder maintain their parallel relationship while they are rotating 
{ HEAD ~ The eccentrics } and cranks associated with { TAIL ~ each piston } and cylinder maintain their parallel relationship while they are rotating
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH