17R-Stage+D Bore Up Kit 106cc H-Cylinder/2B for Monkey, Gorilla, Dax, Magna

【SP武川 01-06-0035 17R-Stage+D Bore Stroke Up Kit 106cc H Cylinder/2B Monkey Gorilla Dax Magna Bore Up Engine Parts Takegawa】
■Product Description
By improving the ports and fin shapes from the conventional R-Stage+D and adopting a new camshaft profile, output at higher RPMs has been further increased!
50mm stroke crankshaft with X-section connecting rod.

■Detailed Description
●17R-Stage+D Cylinder Head
Based on the normal head shape, large diameter valves are adopted: Intake: 26mm / Exhaust: 22.5mm.
(12V Monkey normal valve diameter is Intake: 19mm / Exhaust: 16mm)
In conjunction with the large diameter valves, SP Takegawa's original cylinder head adopts an optimal valve included angle, combustion chamber shape, and port shape.
While the normal head's port diameter is 14mm for both intake and exhaust, the 17R-Stage's port diameter is enlarged to Intake: 24.5mm / Exhaust: 19mm. In addition, by adopting a 3D port shape, combined with the larger diameter valves and ports, it enables smoother flow of more intake and exhaust gases.
Valves: (Intake 26mm / Exhaust 22.5mm, Valve Stem Shaft Diameter 4.5mm)
By reducing the diameter of the stem shaft and machining the waist, the weight increase due to the larger valves is kept to a minimum.
Valve Spring: An optimal spring rate unequal pitch (2-step pitch) single valve spring is adopted to suppress surging at high RPMs.
●Auto Decompression Camshaft
Auto Decompression Function: Even with high-compression, increased displacement engines, the engine can be started with light kick force.
There are three types of camshafts: R-10E, R-15E, and R-20E, which can be interchanged to enjoy different driving performances depending on the intended use.
88cc/Scut 106cc /106cc Kit Included Camshaft: R-10E
●φ52H Cylinder (Aluminum Iron Sleeve Cylinder) / Piston
The external appearance is the same design as the genuine Cub engine cylinder (cylinder height differs).
An M5 temperature sensor can be connected to the side of the cylinder, allowing cylinder temperature to be measured by connecting a separate SP Takegawa compact LCD meter (with M5 temperature sensor), or by changing the sensor part of a thermometer to an M5 temperature sensor.
The piston skirt is molybdenum-coated for better initial break-in.
●Reinforced Crankshaft with X-Section Connecting Rod (2-Point Supported Crankshaft)
Machined from forged material, adopting an X-section shape.
While achieving weight reduction, sufficient strength is ensured, and the diffusion of buckling stress and torsional rigidity are significantly improved. The surface is shot-peened.
A special bearing is adopted that enlarges the inner diameter of the crankshaft's journal bearing.
This allows the shaft diameter of the journal part, where stress concentrates on the crankshaft, to be increased from 20mm to 22mm, thereby improving the shaft's strength.

■Compatible Models
HONDA
12V Monkey/Gorilla (Z50J-2000001~/AB27-1000001~1899999)
Monkey R/RT (AB22-1000017~)
Monkey BAJA (Z50J-1700001~)
12V DAX50 (AB26-1000001~)
CD50 (CD50-1500001~)
CL50 (CD50-4000001~)
Benly50S (CD50-2200005~)
MAGNA50 (AC13-1000010~)
CRF50F (AE03-1400001~)
XR50R (AE03-1000001~)
CRF70F (DE02-1700001~)
XR70R (DE02-1000001~)

■Notes
*Images are for illustration purposes only. Includes products with different sizes and colors.
*Product design and specifications are subject to change without notice. Please be aware.
*To fully demonstrate engine performance when installing the 17R-Stage+D, SP Takegawa carburetor kit and muffler are separately required.
*This product is made-to-order, so cancellations after ordering are not possible.
*Due to being made-to-order, this product may take some time for delivery. Also, please note that the manufacturer may discontinue or change specifications without prior notice.