Checking The Piston Ring End Gap; Duke); Checking/Measuring The Piston - KTM 125 DUKE EU Repair Manual

16 ENGINE
16.4.41 Checking the piston ring end gap (200 Duke)
16.4.42 Checking/measuring the piston (200 Duke)
–
Check the sealing area of the cylinder head for distortion using a straight edge and
the special tool.
Feeler gauge (59029041100) (
Cylinder/cylinder head - distortion of
sealing area
» If the measured value does not equal the specified value:
–
Change the cylinder and piston.
304539-10
–
Remove the piston ring from the piston.
–
Place the piston ring in the cylinder and align it with the piston.
Guideline
Under the upper edge of the cylinder
–
Measure end gap
Guideline
Piston ring end gap
Compression ring
304519-10
Oil scraper ring
Feeler gauge (59029041100) (
» If the end gap is more than the specified value:
–
Check/measure the cylinder. (
» If the cylinder wear is within the tolerance range:
–
Change the piston ring.
–
Mount the piston ring with the marking facing toward the piston head.
–
Check the piston bearing surface for damage.
» If the piston bearing surface is damaged:
–
Change the piston and, if necessary, the cylinder.
–
Check that the piston rings can move easily in the piston ring grooves.
» If the piston ring is stiff:
–
Clean the piston ring groove.
305905-10
–
Check the piston rings for damage.
» If the piston ring is damaged:
–
Change the piston ring.
–
Check the piston pin for discoloration or signs of wear.
» If the piston pin has strong discoloration/signs of wear:
–
Change the piston pin.
–
Insert the piston pin into the connecting rod and check the bearing for play.
» If the piston pin bearing has too much play:
–
Change the connecting rod and the piston pin.
p. 253)
with the special tool.
A
p. 253)
p. 145)
Tip
Use an old piston ring to clean the piston ring groove.
Info
Mount the piston ring with the marking facing upward.
≤ 0.10 mm (≤ 0.0039 in)
20 mm (0.79 in)
≤ 0.40 mm (≤ 0.0157 in)
≤ 0.80 mm (≤ 0.0315 in)
146