Yamaha YZF-R125 Service Manual: Checking the condition of the bulb sockets
The following procedure applies to all of the bulb sockets.
1. Check:
Bulb socket (for continuity)
(with the pocket tester)
No continuity 
Replace.
NOTE:
Check each bulb socket for continuity in the same manner as described in the bulb section, however, note the following.
a. Install a good bulb into the bulb socket.
b. Connect the pocket tester probes to the respective leads of the bulb socket.
c. Check the bulb socket for continuity. If any of the readings indicate no continuity, replace the bulb socket.
Checking the condition of the bulbs
The following procedure applies to all of the
bulbs.
1. Remove:
Bulb
WARNINGSince the headlight bulbs get extremely
hot,
keep flammable products and your hands
away from them ...
Checking the fuses
The following procedure applies to all of the fuses.
CAUTION:To avoid a short circuit, always turn the
main
switch to "OFF" when checking or replacing
a fuse.
1. Remove:
Ri ...
Other materials:
Assembling the main axle and drive axle
1. Install:
Toothed washer "1"
Circlip "2"
NOTE:
Be sure to install the circlip so that its sharp
edge "a" is facing away from the toothed washer
and gear.
Be sure the circlip ends "b" are positioned at
the axle spline groove "c".
2. Install:
2nd pinion gear "1"
NO ...
Aftermarket Parts, Accessories, and Modifications
While you may find aftermarket products
similar in design and quality to
genuine Yamaha accessories, recognize
that some aftermarket accessories
or modifications are not suitable because
of potential safety hazards to you
or others. Installing aftermarket products
or having other modif ...
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 or
wet areas. Service the drive chain as
follows.
NOTICE
The drive chain must be lubricated
...