Yamaha YBR125 54mm Standard-Bore Piston, Ring & Gasket Kit
Aftermarket top-end engine service kit for selected Yamaha YBR125 2005-2015 motorcycles using the standard 54.00mm bore. Designed for piston replacement, top-end rebuild and engine refresh work where the original cylinder remains at standard bore size.
This listing combines the piston-service parts and gasket components shown in the product photographs. It is intended for workshop repair, engine rebuilding and replacement of worn or damaged top-end components.
Key Features
- For selected Yamaha YBR125 125cc 4-stroke engines
- Standard-bore application: 54.00mm
- Suitable for top-end rebuild / piston replacement work
- Piston-service components supplied as pictured
- Gasket components supplied as pictured
- Aftermarket replacement kit
- Moto Mania SKU: 00919-ENG
Yamaha OE / Manufacturer Cross-References
The following genuine Yamaha numbers are provided as compatibility and identification references. They are not the manufacturer MPN of this unbranded aftermarket kit.
- 5VL-E1631-00 – Yamaha standard piston reference
- 5VL-E1631-10 – later / related standard piston reference
- 5VL-E1633-00 – Yamaha piston pin reference
- 93450-16812 – piston circlip reference
- 5VL-W1161-00 – Yamaha standard piston ring set reference
- 5VL-E1603-00 / 5VL-Y1161-00 – related / superseding ring-set references
- 5VL-E1181-00 – cylinder-head gasket reference
- 5VL-E1351-10 – cylinder-base gasket reference
Researched Applications
- Yamaha YBR125 – selected 2005-2015 standard-bore models
- Yamaha YBR125ED / YBR125E / YBR125ESD – selected 5VL / 3D9 / 51D family applications
- Some Yamaha YB125 and XT125 applications share individual Yamaha piston / ring references, but complete-kit compatibility must be checked before ordering
Standard Bore Information
The standard Yamaha YBR125 piston size is approximately 54.00mm. This listing should not be used for a cylinder that has been rebored to an oversize specification such as +0.50mm or +1.00mm unless the supplied piston is positively measured and confirmed to match.
When This Kit May Be Needed
- Low compression caused by worn piston rings
- Excessive oil consumption or exhaust smoke
- Piston or ring damage during an engine rebuild
- Top-end refresh while retaining a standard-bore cylinder
- Replacement of disturbed or damaged top-end gaskets during piston service
Important Compatibility Checks
Before ordering, compare the existing piston and engine details with the product photographs and Yamaha references above. Check:
- Cylinder bore diameter is standard 54.00mm
- Piston crown profile matches the original
- Piston-pin diameter and length match
- Ring groove layout and ring thickness match
- Gasket shape and bolt / oil-passage holes match the engine
- Engine code / model code matches a compatible YBR125 application
Do not order by “YBR125” model name alone. Yamaha made production and market changes during the model run, and later versions can use different piston-ring or top-end part references.
Delivery & Returns
- Fast UK dispatch
- Free UK delivery where shown on the product page
- 30-day returns subject to the Moto Mania returns policy