The bore may include a first radial inner surface at {TAIL ~ the first lobe member} and {HEAD ~ a second radial inner surface} at the second lobe member 
The bore may include a first radial inner surface at { TAIL ~ the first lobe member } and { HEAD ~ a second radial inner surface } at the second lobe member
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH