# Piston ring

> Piston rings sit in grooves on the piston; they seal combustion pressure, scrape oil off the cylinder wall and carry heat to the cylinder.

- **Also known as:** Piston segmanı, Sekman, Piston rings
- **Turkish term:** Segman
- **Category:** [Pistons & Rings](https://motorsikletparcasi.com/en/category/pistons-and-rings)
- **Page:** https://motorsikletparcasi.com/en/glossary/piston-ring

Four-stroke engines usually have three rings: the **top compression** ring, the **second compression** ring and the **oil control** ring. Rings are sold in standard (STD) or oversize (e.g. 0.25 / 0.50 mm) sizes to match the [piston](https://motorsikletparcasi.com/en/glossary/piston).

## Signs of wear

- Blue exhaust smoke, oil consumption
- Low compression, loss of power, hard starting
- Higher crankcase pressure (oil mist from the breather)

When fitting, measure the ring end gap and stagger the gaps at the angles given in the manual.

## Related terms

- [Piston](https://motorsikletparcasi.com/en/glossary/piston): The piston moves up and down in the cylinder and transfers combustion pressure to the crankshaft through the connecting rod.
- [Cylinder](https://motorsikletparcasi.com/en/glossary/cylinder): The cylinder is the part of the engine in which the piston moves and combustion takes place.
- [Engine oil](https://motorsikletparcasi.com/en/glossary/engine-oil): Engine oil lubricates, cools and cleans the engine's moving parts; on most motorcycles it also lubricates the clutch and gearbox.

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- Source page: https://motorsikletparcasi.com/en/glossary/piston-ring
- Last updated: 2026-10-09
- Türkçe sürüm: https://motorsikletparcasi.com/sozluk/segman.md
- Site overview: https://motorsikletparcasi.com/en/llms.txt
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