Checking The Tappet Covers And Camshaft; Sprocket Cover; Checking The Timing Chain Tensioner; Checking The Camshaft Sprocket - Yamaha YBR250 2007 Service Manual

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CYLINDER HEAD
CHECKING THE TAPPET COVERS AND
CAMSHAFT SPROCKET COVER
1. Check:
• valve covers
• timing sprocket cap
• O-rings
Damage/Wear --> Replace.

CHECKING THE TIMING CHAIN TENSIONER

1. Check:
• timing chain tensioner
Cracks/Damage --> Replace.
2. Check:
• one way came operation
Rough movement --> Replace.
3. Check:
• timing chain tensioner bolt
• gasket New
• timing chain tensioner rod
Damage/Wear --> Replace.
4. Check:
• lock and release the operation
Rough movement --> Replace.

CHECKING THE CAMSHAFT SPROCKET

1. Check:
• camshaft sprocket
Wear/Damage --> Replace the sprocket and
the timing chain as a set.
1 Drive chain
2 Camshaft sproket
2. Check:
• timing chain guide (front)
Damage/Wear --> Replace.
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ENG