TP-002 57Φ Bore-up & Big Valve Cylinder Head Kit (148cc) for CT125 (JA55) and other old horizontal engines

This is a big valve cylinder head for Honda's old horizontal engines. Intake diameter is 28Φ, exhaust diameter is 24Φ. This product cannot be installed on genuine cylinders. It is suitable for cylinders with an inner diameter of 56Φ or more.
The big valves dramatically improve the efficiency of intake and exhaust. In addition, the ports have been enlarged, resulting in a pleasant engine feeling.
High cam and reinforced valve springs are included in the set.

This is a bore-up kit for Honda's old horizontal engines. There are other companies' products with larger displacements, but we have concluded that the 57mm cylinder bore provides the best balance in terms of engine durability and high-speed range extension. After installing this product, we have driven over 10,000km without any trouble even under harsh operating conditions. This is a product that we can recommend with confidence.
*When installing this product on public roads, you will need to apply for changes to your license, insurance, taxes, etc. Please take care of these yourself.