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SP Takegawa

Takegawa Superhead 4V+R Big Bore Kit 145cc

Takegawa Superhead 4V+R Big Bore Kit 145cc

01-05-0644

$1,103.00 USD
$1,103.00 USD
Sale Sold out

Superhead 4V+R (1-cam 4-valve) cylinder head


Utilizing two intake and exhaust valves each, the valve curtain area is expanded and the efficiency of air intake and exhaust is greatly enhanced, surpassing that of standard two-valve systems. The head shape has been meticulously crafted to optimize the center plug, valve pinch angle, combustion chamber and port design, resulting in a powerful and consistent output in high RPMs - a defining characteristic of the Super Head. The integration of 1 cam and 4 valves has allowed for a lightweight and compact design, while still delivering unmatched performance as the most robust SOHC head on the market.

■The Takegawa Superhead 4V+R Big Bore Kit 145cc includes roller rocker arms with built-in bearings, similar to those found in stock models. This design effectively reduces frictional resistance between the camshaft and roller bearings, providing smooth tracking of the cam profile at both low and high RPM.

■Valve
The intake and exhaust valves each have a diameter of 21.5mm and 18.5mm, respectively, while the valve stem shafts for both are 4.0mm.

■Valve Spring
Employed is a single valve spring with unequal pitch (2 pitches) to prevent surging at high rpm, and the optimized port diameter perfectly matches the SP Takegawa Big Throttle Body Manifold. Installing the manifold simultaneously allows for a smooth intake and improved performance, making the most of the cylinder head's capabilities. The unique shape of SP Takegawa's cylinder head not only enhances the bike's custom look, but also boasts a die-cast aluminum inspection cover and left cylinder head side cover with a barrel-polished finish. Meanwhile, the oil tower on the right side is crafted from machined aluminum and finished in silver anodized, while other covers add a touch of style and dress-up to the cylinder head.

■M8 Spark Plug
The M8 spark plug was incorporated along with the ideal valve pinching angle and the compact design of the 4-valve system.

■Auto decompression camshaft (10/10D)
The camshaft utilizes ball bearings on both ends to minimize friction in the camshaft journal and improve efficiency. This also includes an auto decompression mechanism which reduces the strain of kick-starting and minimizes the load on the transmission during engine launch, allowing for effortless starting even with higher displacement engines.

■Cylinder
The Takegawa Superhead 4V+R Big Bore Kit 145cc features an aluminum steel sleeve cylinder with a bore diameter of 54mm, stroke of 63.1mm (stock), and compression ratio of 12.0:1. Optional add-ons include the SP Takegawa M5 temperature sensor and a separate thermometer (compact LED with M5 temperature sensor) for precise cylinder temperature measurement.

■Piston
The piston body is crafted from cast aluminum and meticulously machined to achieve a perfect balance of lightweight construction and exceptional stiffness.
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