Husqvarna SMR Owner's Manual page 71

b) Piston diameter (Dp)
Take the piston diameter at "B" distance of 6 mm/0.24 in. (TE-
TC 250), 9 mm/0.35 in. (TC 450-510), 10 mm/0.39 in. (TE-
SMR 450) o 11 mm/0.43 in. (TE-SMR 510) from the base.
CLEARANCE
250: 0,020÷0,046 mm
250: 0.00079÷0.00181 in.
450-510: 0,025÷0,055 mm
450-510: 0.0010÷0.00216 in.
WEAR LIMIT
250: 0,10 mm
250: 0.004 in.
450-510: 0,12 mm
450-510: 0.0047 in.
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