Honda CG125 Titan 2000-2001 56.5mm / 15mm Top-End Kit
Aftermarket cylinder and piston kit for documented Honda CG125 Titan 125 applications using a 56.5 mm bore and 15 mm piston pin.
Technical Specification
- Part type: Standard-bore cylinder / barrel and piston top-end rebuild kit
- Engine family: Honda CG125-style air-cooled OHV / pushrod 4-stroke single
- Nominal displacement: 124cc / 125cc
- Standard bore: 56.50 mm
- Stroke of the classic CG125 engine family: 49.50 mm
- Piston pin / gudgeon pin diameter: 15 mm
- Typical old-model CG125 piston overall length: approx. 52 mm
- Typical old-model CG125 piston crown height: approx. 15.5 mm
- Cooling: Air cooled
- Condition: Brand new aftermarket replacement
Important Engine-Type Correction
The classic Honda CG125 was designed around a short-pushrod OHV engine. Honda's own development history and period specifications describe the CG125 as an OHV / pushrod engine. Some generic aftermarket adverts incorrectly call similar 56.5 mm kits “OHC”. This listing does not rely on that inaccurate wording.
What This Kit Is For
This kit is intended for a standard-bore top-end rebuild where the original cylinder or piston is worn, scored or damaged, compression is low, or the engine is being restored. The 56.5 mm bore and 15 mm piston pin are critical fitment dimensions.
Typical Kit Contents
The source listing identifies a cylinder / barrel and piston kit. Comparable kits in this exact 56.5 mm / 15 mm family commonly include:
- 1 x cylinder / barrel
- 1 x 56.5 mm piston
- Piston ring set
- 15 mm gudgeon / wrist pin
- Piston-pin circlips
- Head and base gaskets
- Some kits also include valve-stem seals
Use the listing photographs as the final guide to the exact components supplied with SKU 00921-ENG. Do not assume every item listed above is included if it is not visible in your stock photographs.
Critical Fitment Checks
- Measure the existing cylinder bore: this kit is 56.50 mm standard bore.
- Measure the piston pin: this kit is the 15 mm pin version.
- Compare cylinder overall / effective height, crankcase spigot, stud spacing and oil-way arrangement.
- Compare piston crown, compression height and ring layout.
- Confirm the engine is the CG125-style OHV / pushrod architecture and not a visually similar OHC / YBR-type 125 engine.
- Later CG125 / CG125ES / XR125-style applications can use a 13 mm piston pin and different KGA-series cylinder / piston parts. Do not fit this 15 mm kit to a 13 mm-pin engine.
Installation Guidance
Top-end assembly requires correct piston orientation, ring positioning, circlip installation, gasket alignment, valve adjustment and cylinder-head torque. Check the connecting-rod small end and piston-pin fit before assembly. Lubricate the bore and piston during installation, rotate the engine by hand before starting, and use an appropriate running-in procedure after rebuilding.
Professional fitting is recommended if you are not experienced with OHV motorcycle engines.
Package / Brand Note
This is an aftermarket / unbranded replacement part. Honda names and engine references are used only to identify the intended application and are not a claim that the product is Genuine Honda.
Documented / Supported Fitment
- Honda CG125 Titan - documented 2000-2001 125cc application
- Standard bore: 56.50 mm
- 15.00 mm piston pin documented on the matching aftermarket cylinder-kit specification
- OHV / pushrod 4-stroke CG125-family architecture
Fitment note: CG125 Titan production spans multiple engine revisions. This dedicated listing is restricted to the documented 2000-2001 56.5 mm / 15 mm application; later 13 mm-pin CG125 engines are excluded.