Derbi Dirtboy 10, Руководство по ремонту

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I
NSPECTING THE VALVES
- Insert the valves into the cylinder head.
- Alternately test the intake and exhaust valves.
- The test is carried out by filling the manifold with petrol and
checking that no petrol oozes through the valves when these
are pressed with one finger.
- Measure the diameter of the valve stem at the three posi-
tions shown in the figure.
- Calculate the clearance between the valve and the valve
guide.
- Check that the mating surface with the adjuster articulated
terminal is not worn.
- Should the valve sealing area be greater than the prescri-
bed limit, or if any bending or gaps are noted, replace the
valve.
- If no anomalies are found during the above checks, the
same valves can be reused.
- For best sealing results, it is advisable to grind the valves.
- Grind the valves gently with a fine-grained lapping com-
pound.
- During the grinding, keep the cylinder head in a horizontal
position. This will prevent the lapping compound residues
from penetrating between the valve stem and the guide.
CAUTION
TO AVOID SCORING THE MATING SURFACE, DO NOT KEEP
ROTATING THE VALVE WHEN NO LAPPING COMPOUND
IS LEFT. CAREFULLY WASH THE CYLINDER HEAD AND THE
VALVES WITH A SUITABLE PRODUCT FOR THE TYPE OF LA-
PPING COMPOUND BEING USED.
ENGINE EE
- CYLINDER ASSY. AND TIMING SYSTEM
ENGINE
- CYLINDER ASSY. AND TIMING SYSTEM
I
NSPECTING THE VALVES