1. Deburr:
- Valve stem end (with an oil stone)
![](https://motoinstruction.ru/img/yamaha/20/126656.jpg)
2. Lubricate:
- Valvestem "1"
- Valve stem seal "2" (with the recommended lubricant)
Recommended lubricant. Molybdenum disulfide oil.
![](https://motoinstruction.ru/img/yamaha/20/126657.jpg)
3. Install:
- Lower spring seat "1"
- Valve stem seal "2"
- Valve "3"
- Valve spring "4"
- Upper spring seat "5" (into the cylinder head)
- Make sure each valve is installed in its original place. Refer to the following embossed marks.
Intake valve: Blue paint mark
Exhaust valve: "14B"
- Install the valve springs with the larger pitch "a" facing up.
- When installing the valve stem seal to the valve guide, apply silicon fluid to the valve stem seal.
![](https://motoinstruction.ru/img/yamaha/20/126658.jpg)
b. Smaller pitch
4. Install:
- Valve cotters "1"
Install the valve cotters by compressing the valve spring with the valve spring compressor "2" and the valve spring compressor attachment "3".
Valve spring compressor 90890-04019 YM-04019.
Valve spring compressor attachment 90890-04108.
Valve spring compressor adapter 22 mm YM-04108.
![](https://motoinstruction.ru/img/yamaha/20/126659.jpg)
5. To secure the valve cotters onto the valve stem, lightly tap the valve tip with a soft-face hammer.
Notice: Hitting the valve tip with excessive force could damage the valve.
![](https://motoinstruction.ru/img/yamaha/20/126660.jpg)
6. Lubricate:
- Valve pad
- Valve lifter (with the recommended lubricant)
Recommended lubricant. Molybdenum disulfide oil.
7. Install:
- Valve pad
- Valve lifter
- The valve lifter must move smoothly when rotated with a finger.
- Each valve lifter and valve pad must be reinstalled in its original position.