MSX 2013-2020 (JC61-JC75)
125 Monkey 2018-2020 (JB02)
[Valve diameter] IN: 25mm x 2 / EX: 21.5mm x 2
[Valve stem shaft diameter] 4.5mm for both IN and EX
For competition use only.
*When installing the Big Bore Kit, it is recommended to install SP Takegawa's Special Clutch Kit to prevent clutch slippage and various exhausts at the same time.
Based on the "Super Head 4V+R" which achieves the highest class of OHC output characteristics, the "Super Head 4V+R (5-axis port machining) " is a high-precision machining of the intake port by 5-axis machining center for further improvement of the output performance)"
■Super Head 4V+R (5 Axis Port Machining) Cylinder Head Details
Two intake / exhaust valves are used each to increase the valve curtain area and achieve high intake / exhaust efficiency.
The original head shape was designed to balance the center plug, valve pinching angle, combustion chamber shape, and port shape to achieve a higher output than the stock head.
The combustion chamber is finished with high accuracy by NC machining.
■Intake port machined by 5-axis machining center
In order to improve the power output at higher rpm, the optimum intake port shape was designed and the port was machined by 5-axis machining center.
The intake ports are precisely machined by 3D programming, and are beautifully smoothed to achieve high intake efficiency.
■Valves / Valve Springs / Rocker Arms / Camshafts
・Valve Diameter IN: 25mm x 2 / EX: 21.5mm x 2
Valve Stem Shaft Diameter: 4. 5mm for both IN and EX
・Unequal pitch valve spring: It prevents surging at high RPM.
・Forged aluminum roller rocker arms are used.
The frictional resistance with the camshaft is reduced, and smooth operation is realized.
・Auto decompression camshafts (standard 10 / 10D camshafts)
Smooth engine starting is possible without placing a burden on the starter.
・Optional parts: 15 / 15D Camshaft
It improves the output performance in the mid to high RPM range.See the comparison graph.
■Special manifold machined by 5-axis machining center is adopted.
The manifold has also been 5-axis machined to allow smooth intake to the 5-axis machined intake port.
The 3D programmed manifold is beautifully smoothed to enhance the intake effect.
■Cylinder & High Comp Piston
・Cylinder
The cylinder is an all aluminum ceramic cylinder with excellent durability, airtightness and heat dissipation.Black painted surface.
An oil outlet is provided so that oil can be taken out to the oil cooler.
SP Takegawa Oil Cooler Kit is recommended.Please see our web catalog.
An M5 sensor can be mounted on the oil plug bolt.
You can measure the cylinder temperature by purchasing SP Takegawa's compact LED thermometer set with M5 temperature sensor.
・High compression piston (compression ratio 12.5: 1 is adopted)
Pistons designed for high performance and durability.
The piston top is NC machined for high precision.
***FUEL CONTROLLER/ECU MUST BE USED TO ADJUST FUELLING**