Variable displacement radial piston fluid working machine

A variable displacement radial piston fluid working machine, the fluid working machine comprising:

• an inward ring and an outward ring around the inward ring;
• one of the inward ring and the outward ring comprising a rotatable ring cam, the other comprising a plurality of radially extending cylinders circumferentially spaced around the respective ring, each cylinder having a piston reciprocably mounted therein;
• a drive shaft coupled to the ring cam;
• the outward ring comprising first and second axially spaced structural members and a plurality of demountable blocks demountably retainable therebetween, each of the plurality of demountable blocks comprising either more than one of said plurality of cylinders or a segment of the ring cam respectively, each said block being mountable to locate one or more said cylinders in opposing relation to a portion of the ring cam to enable the pistons to be driven by the ring cam and demountable to expose the inward ring for access.