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ring gear

Glossary “ring gear” Definition:
1). The gear around the edge of a flywheel. 2). A large, circular gear such as that in the final drive assembly. 3). The outermost member of a plantary gearset which has teeth in the inside circumference.

ring expander

Glossary “ring expander” Definition:
Flexible spring-steel part placed behind certain piston rings to increase ring pressure on the cylinder wall. May also refer to a tool that is used in the installation of piston rings, which aids in their installation.

ring gap

Glossary “ring gap” Definition:
The gap between the ends of a piston ring installed in the cylinder generally 0.004 inch (about 0.1 mm) for each inch (25.4 mm) of cylinder diameter.