Husqvarna TE 250 Workshop Manual page 460

FRAME AND WHEELS
Rear sprocket, transmission sprocket and drive chain
The figure shows the outline of teeth in normal and excessive wear.
1- Normal consumption
2- Excessive consumption
Should the sprocket be badly worn out, replace it by loosening the six fastening
screws to the hub.
After every rear sprocket replacement, also replace the drive sprocket
and transmission chain.
TIGHTENING TORQUES
3: 34.3 Nm/ 3.5 Kgm/ 25.3 ft-lb +LOCTITE 243
Y.14 Part. N. 8000 B0148 (02-2008)