Husqvarna 2011 SMS 125, Workshop Manual

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G.7
ENGINE OVERHAUL
Ed. 05-2011
Cylinder to piston clearance
The piston-cylinder units are supplied already coupled; should the cylinders
and pistons of some units have been accidentally mixed up, it will be necessary
to measure the diameters as outlined in the previous paragraphs.
Take these measurements at a stabilised temperature of 20°C.
Preferential clearance DN-D1 = 0.035÷0.055 mm
(0.00138÷0.00216 in.)
Wear limit 0.080 mm (0.00315 in.).
Piston pin
It must be perfectly smooth, with no signs of scuffing, dents or bluing due to
overheating. Check the piston pin to piston clearance: it shall be 0.002÷0.009
mm (0.000079÷0.000354 in.). Wear limit 0.012 mm (0.0005 in.). When replac -
ing the piston pin it is also necessary to replace the needle roller bearing cage
(in compliance with what specified in the paragraph "piston pin-piston-connect -
ing rod small end clearance").
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Cylinder Piston
Abbreviation
Size Abbreviation Size Clearance
A-B or BLACK-BLUE
53.985÷53.995
(2.1254÷2.1258)
A - B
53.940÷53.950
(2.1236÷2.1240)
from 0.035 (0.00138 in.)
to 0.055 (0.00216 in.)
C-D or PINK-GREEN
53.995÷54.005
(2.1258÷2.1262)
C - D
53.950÷53.960
(2.1240÷2.1244)
from 0.035 (0.00138 in.)
to 0.055 (0.00216 in.)
E-F or RED-WHITE
54.005÷54.015
(2.1262÷2.1266)
E - F
53.960÷53.970
(2.1244÷2.1248)
from 0.035 (0.00138 in.)
to 0.055 (0.00216 in.)
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