CYLINDER KIT 01-17 HONDA CBR FS SONIC 125 R 58mm BORE PISTON RINGS GASKETS 12100-KGH-900

This 58 mm cylinder piston gasket rebuild kit is an aftermarket top-end replacement designed to restore the cylinder and piston assembly on compatible Honda 125 cc engines. It is intended for repair work involving low compression, cylinder blow-through, piston seizure, or cylinder failure, and includes the main components required for a cylinder, piston and gasket rebuild. The kit originates from the Honda Sonic 125 engine platform, which shares the same engine platform as the European CBR125R and Indonesian CS1 4-stroke engines; for CBR125R installation, crankcase surface modification may be required due to differences in cylinder surface design.

Features

• Suitable for addressing low compression, piston seizure, cylinder blow-through, or cylinder failure


• Includes cylinder, piston, piston rings, wrist pin, circlips and a full top-end gasket kit


• Anodised piston construction supports improved heat resistance and service life


• High-performance gasket materials support increased reliability


• Cost-effective aftermarket replacement for original top-end components


• Modification allows compatibility with both Sonic and CBR engines after correct fitting preparation

Specifications

• Bore diameter: 58 mm STD


• Stroke: 47.2 mm


• Piston pin diameter: 13 mm


• Piston pin material: Steel


• Compression ratio: 11:1


• Standard bore size: 58 mm x 47.2 mm stroke

Cross-Reference OEM Part Numbers

• Cylinder: 12100-KGH-900


• Cylinder base gasket: 12191-KGH-901


• Cylinder head gasket: 12251-KTY-D30


• Piston STD: 13101-KGH-902


• Piston pin: 13111-KGH-903


• Piston ring set STD: 13011-KGH-305


• Piston circlips: 13115-GN5-910


• Tensioner gasket: 14560-KGH-900


• Valve stem seal: 12209-GB4-682

Vehicle Fitments

• Honda CBR125R, 2004–2017


• Honda FS125 Sonic, 2001–2008

Installation Notes

• The cylinder surface design differs slightly between Sonic and CBR125 models


• For CBR125R installation, modification of the crankcase surface is required to eliminate any gap


• Modification methods may include welding or using a two-component epoxy aluminium adhesive


• After modification, the cylinder is suitable for use with Sonic and CBR engines

Package Includes

• 1 x 58 mm cylinder, 12100-KGH-900


• 1 x piston


• 1 x piston ring set


• 1 x wrist pin


• 2 x circlips


• 1 x cylinder base gasket, 12191-KGH-901


• 1 x cylinder head gasket


• 1 x tensioner gasket