Yamaha WR45OFR service manual Runout limit 01 mm 0.0004

VALVES AND VALVE SPRINGS

ENG

5.Measure:

●Runout (valve stem)

Out of specification → Replace.

Runout limit:

0.01 mm (0.0004 in)

NOTE:

●When installing a new valve always replace the guide.

●If the valve is removed or replaced always replace the oil seal.

6.Eliminate:

●Carbon deposits

(from the valve face and valve seat)

7.Inspect:

●Valve seats

Pitting/wear → Reface the valve seat.

8.Measure:

●Valve seat width a

Out of specification → Reface the valve seat.

Valve seat width:

Intake:

0.9~ 1.1 mm (0.0354 ~ 0.0433 in) <Limit>: 1.6 mm (0.0630 in)

Exhaust:

0.9~ 1.1 mm (0.0354 ~ 0.0433 in) <Limit>: 1.6 mm (0.0630 in)

Measurement steps:

●Apply Mechanic’s blueing dye (Dykem) b to the valve face.

●Install the valve into the cylinder head.

●Press the valve through the valve guide and onto the valve seat to make a clear pattern.

●Measure the valve seat width. Where the valve seat and valve face made contact, blueing will have been removed.

●If the valve seat is too wide, too narrow, or the seat is not centered, the valve seat must be refaced.

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