Bore Diameter: 59mm
Compression Ratio: 12.3: 1
It is possible to use the STD cylinder head and STD crankshaft as it is, and can be changed to 138cc by changing the cylinder and the piston.
The cylinder adopts a ceramic-plated cylinder excellent in air-tightness, durability and heat dissipation.
Because it is possible to attach a stick temperature sensor to SP TAKEGAWA bore up cylinder, it is possible to measure the cylinder temperature separately by purchasing a thermometer.
It adopts a piston shape which balances the shape of the combustion chamber and Compression Ratio, has high combustion efficiency, and has a reduced weight. It applies a molybdenum coat to the piston skirt part, making a good initial familiarity.
It is a camshaft pursuing an optimal camshaft profile that maximizes the performance of a STD cylinder head
*It has been eliminated the decompression mechanism for replacing the included camshaft sprocket and sports camshaft.
*When installing SCUT 138cc big bore Kit, Motorized Bicycle 2-types Registration can not be registered.
*It requires to replace the carburetor and exhaust system.