Super Head 4V+R 124cc Kit, 2-Bearing Crankshaft for Monkey, Gorilla

【SP武川 01-06-0041 Super Head 4V+R 124cc Kit, 2-Point Support Crankshaft for Monkey Gorilla, Big Bore Engine Parts, Takegawa】
■Product Description
This kit features the Super Head 4V+R cylinder head.
124cc. 2-point support crankshaft.
Bore diameter: 54mm. Stroke volume: 54mm. Compression ratio: 12.6:1.
Included camshaft: 15/20D

■Detailed Description
●Features of Super Head 4V+R (1-cam, 4-valve)
Compared to SP Takegawa's Super Head +R large-diameter 2-valve, by having two intake valves and two exhaust valves each, the valve curtain area can be further expanded, enabling higher intake and exhaust efficiency than large-diameter 2-valves.
Furthermore, due to the head design which balances the center plug, valve included angle, combustion chamber shape, and port shape that accompany the 4-valve conversion, it enables high output and achieves the sustained output characteristics at high RPMs that are a major feature of the Super Head.
By adopting a 1-cam, 4-valve system, it was possible to achieve lightness and compactness as much as possible, and at the same time, condense the performance as the strongest SOHC head.
●New Shape Super Head 4-Valve +R Body
The rounded cylinder head shape perfectly matches the Monkey style, enhancing the vehicle's custom image.
In addition, each die-cast head cover, which has undergone barrel polishing, beautifully enhances the cylinder head.
●Valve Features
Valve diameter: Intake: 21.5mm x 2 / Exhaust: 18.5mm x 2
Valve stem shaft diameter: Both intake and exhaust are 4.0mm.
●Valve Spring
Adopting an unequal pitch prevents surging at high RPMs.
●IN/EX Port Features
The port diameter is optimized to match SP Takegawa's 3D manifold.
By installing it simultaneously with the 3D manifold, it enables smooth intake effect without resistance from the carburetor to the combustion chamber, maximizing the performance of the cylinder head.
●Adoption of Roller Rocker Arm
By adopting a roller rocker arm, the output performance of the Super Head +R is maximized, increasing output in the mid to high RPM range and maintaining output in the high RPM range, which is a feature of roller rocker arms.
Roller rocker arms reduce the friction resistance with the camshaft that occurs with slipper-type rocker arms (genuine part type), and the roller bearings built into the rocker arm smoothly follow the cam profile from low to high RPMs.
●M8 Spark Plug
An M8 spark plug is adopted due to the optimal valve included angle from the 4-valve conversion and the compact head.
●Hollow Camshaft (Auto Decompression Mechanism)
The camshaft employs ball bearing support at both ends, reducing friction resistance in the camshaft journal area.
In addition to the included camshaft, optional camshafts are available, so you can change them according to your application and enjoy the riding performance.
Included camshaft: 15/20D
●Auto Decompression Mechanism
This mechanism reduces the kick-start force and the load on the transmission when starting the engine, allowing for smooth engine starting even with a large displacement.
●Ceramic Plated Cylinder / Piston
HA cylinder bore diameter 54mm
Adopts an all-aluminum ceramic plated cylinder with excellent durability, airtightness, and heat dissipation.
The cylinder comes standard with a temperature sensor mounting point.
You can measure the cylinder temperature by purchasing an SP Takegawa thermometer-equipped meter or a thermometer.
For 124cc HA cylinder: M5 temperature sensor
●Piston
A cast piston is adopted, and the piston skirt is coated with molybdenum to ensure good initial break-in.
●X-section connecting rod, 54mm stroke-up crankshaft (R-Type)
Adopts an X-section connecting rod. Machined from forged material, it features an X-section shape.
While reducing weight, it ensures sufficient strength and significantly improves the dispersion of buckling stress and torsional rigidity.
A special bearing with an enlarged inner diameter for the crankshaft journal bearing is adopted.
This makes it possible to increase the shaft diameter of the journal part, where stress concentrates on the crankshaft, from 20mm to 22mm, thereby strengthening the shaft.

■Compatible Models
HONDA
12V Monkey Gorilla (Z50J-2000001～)(AB27-1000001～1899999)
*Crankcase boring is required.

■Notes
*Images are for illustration purposes only. Includes products of different sizes and colors.
*Product designs and specifications may change without prior notice. Please understand.
*When installing the 124cc kit, crankcase modification is required.
*When installing the 124cc/125cc/138cc kit, the engine length will increase, and the engine will interfere with the tire if using standard front forks and standard top bridge & stem, so the front end needs to be changed.
*In the case of Monkey/Gorilla. We recommend simultaneously installing various SP Takegawa front fork kits.
*In the case of CRF50F/XR50R・CRF70F/XR70R. SP Takegawa does not sell front fork kits or similar products. Although aftermarket frames and front fork kits are sold, SP Takegawa has not confirmed their installation compatibility. Please install them on your vehicle at your own risk.
*SP Takegawa Dig Crosser exhaust cannot be installed simultaneously.
*Since this product is made to order, cancellations after ordering are not possible.
*This is a made-to-order product, so delivery may take some time. Also, please note that the manufacturer may discontinue the product or change specifications without prior notice. Thank you for your understanding.