Yamaha YZF-R125 Owners Manual: Drive chain slack
The drive chain slack should be checked before each ride and adjusted if necessary.
To check the drive chain slack
- Place the motorcycle on the sidestand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
- Shift the transmission into the neutral position.
- Move the rear wheel by pushing the motorcycle to locate the tightest portion of the drive chain, and then measure the drive chain slack as shown.
| Drive chain slack: 30.0-40.0 mm (1.18-1.57 in) |
-
Drive chain slack
- If the drive chain slack is incorrect, adjust it as follows.
To adjust the drive chain slack
- Loosen the axle nut and the locknut on each side of the swingarm.
-
Axle nut
-
Drive chain slack adjusting bolt
-
Locknut
-
Alignment marks
- To tighten the drive chain, turn the drive chain slack adjusting bolt on each side of the swingarm in direction (a). To loosen the drive chain, turn the adjusting bolt on each side of the swingarm in direction (b), and then push the rear wheel forward. NOTICE: Improper drive chain slack will overload the engine as well as other vital parts of the motorcycle and can lead to chain slippage or breakage. To prevent this from occurring, keep the drive chain slack within the specified limits.
TIP
Using the alignment marks on each
side of the swingarm, make sure that
both drive chain pullers are in the same
position for proper wheel alignment.
- Tighten the axle nut, then the locknuts to their specified torques.
| Tightening torques: Axle nut: 85 Nm (8.5 m.kgf, 61 ft.lbf) Locknut: 16 Nm (1.6 m.kgf, 11 ft.lbf) |
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrication
chart. In addition, have the brake
hose replaced every four years or
whenev ...
Cleaning and lubricating the drive chain
The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrication
chart, otherwise it will quickly wear
out, especially when riding in dusty ...
Other materials:
Removing the crankshaft
1. Remove:
Crankshaft "1"
NOTE:
Remove the crankshaft with the crankcase
separating tool "2".
Make sure the crankcase separating tool is
centered over the crankshaft.
CAUTION:
To protect the end of the crankshaft, place
an appropriate sized socket between the
c ...
Checking the camshaft sprocket and timing chain guide
1. Check:
Camshaft sprocket
More than 1/4 tooth wear "a" Replace
the
camshaft sprocket, timing chain and crankshaft
as a set.
a. 1/4 tooth
b. Correct
1. Timing chain roller
2. Camshaft sprocket
2. Check:
Timing chain guide (exhaust side)
Damage/wear Replace.
...
Checking the drive sprocket
1. Check:
Drive sprocket
More than 1/4 tooth "a" wear
Replace the
drive chain sprockets as a set.
Bent teeth Replace the drive
chain sprockets
as a set.
b. Correct
1. Drive chain roller
2. Drive chain sprocket
Checking the rear wheel sprocket
Refer to "CHECKING AND R ...