# Camshaft

> The camshaft uses its cam lobes to open and close the valves at the right time.

- **Also known as:** Kam mili, Eksantrik, Camshaft, Külbütör
- **Turkish term:** Eksantrik mili
- **Category:** [Camshafts](https://motorsikletparcasi.com/en/category/camshafts)
- **Page:** https://motorsikletparcasi.com/en/glossary/camshaft

On four-stroke engines the camshaft turns at half crankshaft speed and is driven by a [cam chain](https://motorsikletparcasi.com/en/glossary/cam-chain) (a belt or gears on some engines). Engines can be single overhead cam (SOHC) or double overhead cam (DOHC); on SOHC engines the lobes usually act on the valves through rocker arms.

- Worn lobes open the valves less, causing power loss and noise.
- Lobes and rocker faces wear quickly without oil.
- When fitting, align the timing marks correctly with the crank.

## Related terms

- [Valve](https://motorsikletparcasi.com/en/glossary/valve): A valve is the mushroom-shaped part in the cylinder head that opens and closes the intake and exhaust ports.
- [Cam chain](https://motorsikletparcasi.com/en/glossary/cam-chain): The cam chain (timing chain) drives the camshaft from the crankshaft and keeps valve timing in sync.
- [Valve clearance](https://motorsikletparcasi.com/en/glossary/valve-clearance): Valve clearance adjustment sets the gap between the valve stem and the part that opens it (rocker or bucket) to the value in the manual.
- [Cylinder head](https://motorsikletparcasi.com/en/glossary/cylinder-head): The cylinder head closes the top of the combustion chamber and carries the valves, camshaft and spark plug.

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- Source page: https://motorsikletparcasi.com/en/glossary/camshaft
- Last updated: 2026-10-09
- Türkçe sürüm: https://motorsikletparcasi.com/sozluk/eksantrik-mili.md
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