Yamaha 2002 YB50, Service Manual

Page: 62 / 161

ENG
INSPECTION AND REPAIR
4-11
INSPECTION AND REPAIR
CYLINDER HEAD
1. Eliminate:
• Carbon deposits Use a rounded scraper
2. Inspect:
• Cylinder head warping.
Outside specified value Rectify
Steps for measuring warping and rectifica-
tion:
• Join a straight edge and a thickness cali-
bration on the cylinder head
• Measure the limit of the warping
• If the warping is outside the specified value,
rectify the cylinder head
NOTE:
Turn the cylinder head several times to avoid
removing too much material from one side
CYLINDER AND PISTON
1. Eliminate:
• Carbon deposits Use a rounded file
2. Inspect:
• Cylinder wall Wear/striping Rectify or
change
3. Eliminate:
• Carbon deposits
From the piston crown and ring grooves.
Warping limit
0.02 mm