# 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.

- **Also known as:** Supap ayarı, Valf boşluğu, Subap boşluğu, Valve adjustment
- **Turkish term:** Subap ayarı
- **Category:** [Valves & Rocker Arms](https://motorsikletparcasi.com/en/category/valves-and-rocker-arms)
- **Page:** https://motorsikletparcasi.com/en/glossary/valve-clearance

The gap is measured with feeler gauges with the engine **cold** and the piston at top dead centre on the compression stroke. Intake and exhaust have different values; the values and check interval are in the owner's manual.

- **Too little clearance:** the valve does not close fully; compression drops, starting gets hard and the valve can burn.
- **Too much clearance:** ticking from the top of the engine, and the valves open late.
- It is adjusted with a screw on screw-type rockers, or by fitting a shim of different thickness on bucket-and-shim engines.

## 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.
- [Camshaft](https://motorsikletparcasi.com/en/glossary/camshaft): The camshaft uses its cam lobes to open and close the valves at the right time.
- [Idle speed](https://motorsikletparcasi.com/en/glossary/idle-speed): Idle speed is the lowest engine speed at which the engine keeps running with the throttle closed.

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- Source page: https://motorsikletparcasi.com/en/glossary/valve-clearance
- Last updated: 2026-10-09
- Türkçe sürüm: https://motorsikletparcasi.com/sozluk/subap-ayari.md
- Site overview: https://motorsikletparcasi.com/en/llms.txt
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