138cc Takegawa Super Head +R Bore up Kit

■ Super Head + R

By adopting the original super head technology and internal structure in the cylinder head adopting the standard shape, OHC highest class large diameter valve and appropriate valve intersection angle are made possible to achieve high output characteristics and high rotation speed range Stable output characteristics have been realized.

 
■ Valve diameter

Intake valve diameter: 30 mm

Exhaust valve diameter: 24.5 mm

Valve stem shaft diameter IN / EX together 4.5 mm

 
■ Characteristics

of valve Valve stem Shaft shaft is made thinner and waist processing added We are trying to reduce weight and reduce weight loss.

 
■ Valve Spring

Adopted Double Spring of Inner Spring and Outer Spring (Unequal Pitch)

 
■ Valve Spring Retainer (Steel Standard Equipped) There

is "Special Valve Spring Retainer, Tappet Adjusting Nut (Titanium Alloy)" as an Optional Part.

By changing the retainer to titanium alloy and reducing the weight, the weight of the dynamic valve system is reduced, and the followability in the high revolution range is improved. 

 
Roller rocker arm (aluminum forged)

■ Adopted a roller rocker arm

Aluminum forged rocker arm with roller bearing built in.

For slipper type rocker arms, slipper parts are made roller bearings to reduce friction loss and follow the cam profile smoothly from low speed to high speed. By adopting the roller bearing, the added weight overcomes the weight increase by making the rocker arm body aluminum forged.

Auto decompression camshaft

■ Auto decompression camshaft (attached camshaft: S - 20D)

Provide an oil line at the center of the camshaft and guide the oil to the cam sprocket. This increases the durability and lubrication effect on the cam chain.

Also, by providing an oil jet passage on the camshaft cam face and spraying oil from the cam face against the rocker arm, cooling and lubrication can be performed effectively.

The camshaft journal adopts both end ball bearing support and reduces the frictional resistance to the camshaft from startup and low speed.

■ Auto Decompression Function Even with a

large displacement engine, you can start the engine with a light kick power.

There are 4 types of camshafts with different cam profiles, and can be exchanged for use.

■ Cylinder / piston

The cylinder adopts a ceramic plated cylinder excellent in airtightness, durability and heat dissipation.

Since our stick temperature sensor can be installed in our bore up cylinder, you can measure the cylinder temperature separately by purchasing a thermometer.

Piston
Combustion chamber shape and compression ratio are balanced, combustion efficiency is high, piston shape with reduced weight is adopted. Maximize the performance of Super Head + R. Molybdenum coat is applied to the piston skirt part, and good initial familiarity is made. 

Optional parts

: Special valve spring retainer (titanium alloy) (2 pieces) 01-12-084

: Titanium alloy tappet adjusting nut (2 pieces) 00-01-0172