In another embodiment, the rotary slide valve has a rotor which is formed by the crankcase and {HEAD ~ a stator} which is {TAIL ~ a ring housing} 
is
In another embodiment , the rotary slide valve has a rotor which is formed by the crankcase and { HEAD ~ a stator } which is { TAIL ~ a ring housing }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL