KTM 125 SX EU 2015, Owner'S Manual

Page: 57 / 129

11 SERVICE WORK ON THE CHASSIS
55
11.36 Checking the chain tension
Warning
Danger of accidents Danger caused by incorrect chain tension.
–
If the chain is too taut, the components of the secondary power transmission (chain, engine sprocket, rear sprocket, bear-
ings in the transmission and in the rear wheel) will be under additional load. In addition to premature wear, this can cause
the chain or the countershaft of the transmission to break in extreme cases. If the chain is too loose, however, it may fall
off the engine sprocket or rear sprocket and block the rear wheel or damage the engine. Ensure that the chain tension is
correct and adjust it if necessary.
Preparatory work
–
Raise the motorcycle with the lift stand. ( p. 39)
B02103-10
Main work
–
Push the chain at the end of the chain sliding component upwards to measure
chain tension

.
Info
The bottom chain section

must be taut.
Chain wear is not always even; repeat this measurement at different chain
positions.
Chain tension 55… 58 mm (2.17… 2.28 in)
» If the chain tension does not meet specifications:
–
Adjust the chain tension. ( p. 55)
Finishing work
–
Remove the motorcycle from the lift stand. ( p. 39)
11.37 Adjusting the chain tension
Warning
Danger of accidents Danger caused by incorrect chain tension.
–
If the chain is too taut, the components of the secondary power transmission (chain, engine sprocket, rear sprocket, bear-
ings in the transmission and in the rear wheel) will be under additional load. In addition to premature wear, this can cause
the chain or the countershaft of the transmission to break in extreme cases. If the chain is too loose, however, it may fall
off the engine sprocket or rear sprocket and block the rear wheel or damage the engine. Ensure that the chain tension is
correct and adjust it if necessary.
Preparatory work
–
Raise the motorcycle with the lift stand. ( p. 39)
–
Check the chain tension. ( p. 55)
B02105-10
Main work
–
Loosen nut

.
–
Loosen nuts  .
–
Adjust the chain tension by turning adjusting screws  to the left and right.
Guideline
Chain tension 55… 58 mm (2.17… 2.28 in)
Turn adjusting screws

on the left and right so that the markings on the
left and right chain adjusters are in the same position relative to reference
marks

. The rear wheel is then correctly aligned.
–
Tighten nuts

.
–
Make sure that chain adjusters  are fitted correctly on adjusting screws  .
–
Tighten nut

.
Guideline
Nut, rear wheel spindle M25x1.5 80 Nm (59 lbf ft)