Yamaha VMX12H Supplementary Service Manual page 146

I NSPECTI O N AND REPAI R
NO TE:
Af t er i nst al l i ng val ve gui de:
* U se t he 5. 5 m m Val ve G ui de R eam er ( YM -
01196)
val ve st em
t he val ve seat .
C i r cl i p
Val ve gui de
Val ve Seat
1. I nspect
*V al ve seat
W ear / Pi t t i ng/ Val ve r epl acem ent
Resur f ace seat at 45° angl e.
C l ean val ve seat i f pi t t ed or w orn usi ng a 45°
Val ve Seat C ut t er ( YM - 91043)
i ng cut t er, keep an even dow nw ard pressure t o
prevent chat t er m arks.
Sect i on
A
C
2. M easure:
• Val ve seat wi dth
3. Appl y:
• M echani cs bl ui ng dye ( Dykem )
To val ve and seat .
* Fi ne gr i ndi ng com pound ( sm al l am ount )
G r ound sur f ace of val ve f ace.
4. Posi t i on:
I nt o cyl i nder head.
Spi n i t r api dl y back and f or t h, t hen l i f t
val ve and cl ean of f al l gr i ndi ng com pound.
5. Inspect:
W her ever val ve seat and val ve f ace m ade
cont act , bl ui ng w i l l have been r em oved.
t o obt ai n pr oper val ve gui de/
cl ear ance,
, W hen t w i st -
C ut sect i ons as f ol l ow s
Cut t er
30°
45°
B
60°
seat sur f ace
1
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