Subaru Robin Power Products Subaru EX27 - Manual (Page 9)

Rammer Engine
Rammers present a special engineering challenge. The engine must withstand both the vibration of the compactive force and the high dirt
and dust environment. Additionally, rammer engines require a high degree of specialized design to integrate with the rest of the machine for
maximum performance. The rammer design requires that the entire machine be balanced on the center of the foot in both the front to back
axis and side to side axis.
Because the engine is mounted to the side of the rammer’s leg, the lesser the width (W) of the engine, the less the rammer needs to be
angled (A) forward to balance the machine over the foot. As the rammer angle (A) is increased, the compaction force (F1) that impacts the
ground is reduced and the backward force (F2) increases – propelling the rammer forward and reducing compactive force. To maximize
the compaction force, Subaru rammer engines are designed specifically for rammer applications. All Subaru rammer engines are balanced
close to the mounting face as well as evenly on the side to side axis for optimum compaction performance and easy operation.
W
A
F2
F1
EH09 | ER12
2.8-3.5 HP