2017 YAMAHA YS125 suspension

Safety information
1-3
1Avoi
d Car bon Monoxi de Poisonin g
All engine exhaust contains carbon
monoxide, a deadly gas. Breathing
carbon monoxide can cause head-
aches, dizziness, drowsiness, nausea,
confusion, and eventually death.
Carbon Monoxide is a colorless, odor-
less, tasteless gas which may be pres-
ent even if you do not see or smell any
engine exhaust. Deadly levels of car-
bon monoxide can collect rapidly and
you can quickly be overcome and un-
able to save yourself. Also, deadly lev-
els of carbon monoxide can linger for
hours or days in enclosed or poorly
ventilated areas. If you experience any
symptoms of carbon monoxide poi-
soning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREAT-
MENT.  Do not run engine indoors. Even if
you try to ventilate engine exhaust
with fans or open windows and
doors, carbon monoxide can rap-
idly reach dangerous levels.
 Do not run engine in poorly venti-
lated or partially enclosed areas
such as barns, garages, or car-
ports. 
Do not run engine outdoors where
engine exhaust can be drawn into
a building through openings such
as windows and doors.
Loa din g
Adding accessories or cargo to your
motorcycle can adversely affect stabil-
ity and handling if the weight distribu-
tion of the motorcycle is changed. To
avoid the possibility of an accident, use
extreme caution when adding cargo or
accessories to your motorcycle. Use
extra care when riding a motorcycle
that has added cargo or accessories.
Here, along with the information about
accessories below, are some general
guidelines to follow if loading cargo to
your motorcycle:
The total weight of the operator, pas-
senger, accessories and cargo must
not exceed the maximum load limit.
Operation of an overloa ded vehicle
coul d cause an acci dent. When loading within this weight limit,
keep the following in mind:
 Cargo and accessory weight
should be kept as low and close to
the motorcycle as possible. Se-
curely pack your heaviest items as
close to the center of the vehicle
as possible and make sure to dis-
tribute the weight as evenly as
possible on both sides of the mo-
torcycle to minimize imbalance or
instability.
 Shifting weights can create a sud-
den imbalance. Make sure that
accessories and cargo are se-
curely attached to the motorcycle
before riding. Check accessory
mounts and cargo restraints fre-
quently.
• Properly adjust the suspension for your load (suspension-ad-
justable models only), and
check the condition and pres-
sure of your tires.
• Never attach any large or heavy items to the handlebar, front
fork, or front fender. These
items, including such cargo as
sleeping bags, duffel bags, or
Maximum loa d:
171 kg (377 lb)
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Safety information
1-4
1
tents, can create unstable han-
dling or a slow steering re-
sponse.
 This vehicle is not desi gne d to
pull a trailer or to be attached to
a si decar.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail- able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Many companies with no connection
to Yamaha manufacture parts and ac-
cessories or offer other modifications
for Yamaha vehicles. Yamaha is not in
a position to test the products that
these aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer. Aftermarket Parts, Accessories, an
d
Mo difications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accesso-
ries or modifications are not suitable
because of potential safety hazards to
you or others. Installing aftermarket
products or having other modifications
performed to your vehicle that change
any of the vehicle’s design or operation
characteristics can put you and others
at greater risk of serious injury or
death. You are responsible for injuries
related to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.  Never install accessories or carry
cargo that would impair the per-
formance of your motorcycle.
Carefully inspect the accessory
before using it to make sure that it
does not in any way reduce
ground clearance or cornering
clearance, limit suspension travel, steering travel or control opera-
tion, or obscure lights or reflec-
tors.
• Accessories fitted to the han- dlebar or the front fork area can
create instability due to improp-
er weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
• Bulky or large accessories may seriously affect the stability of
the motorcycle due to aerody-
namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become
unstable in cross winds. These
accessories may also cause in-
stability when passing or being
passed by large vehicles.
• Certain accessories can dis- place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
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Safety information
1-5
1operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
 Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires an d Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. Refer to page
6-17 for tire specifications and more in-
formation on replacing your tires.
Transportin g the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle.  Remove all loose items from the
motorcycle. 
Check that the fuel cock (if
equipped) is in the “OFF” position
and that there are no fuel leaks.
 Point the front wheel straight
ahead on the trailer or in the truck
bed, and choke it in a rail to pre-
vent movement.
 Shift the transmission in gear (for
models with a manual transmis-
sion).
 Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mounted
handlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
 The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Instrument and control functions
3-11
3
EAU78851
SeatTo remove the seat
1. Remove panels A and B. (See page 6-8.)
2. Remove the bolts. 3. Lift the front of the seat and pull it
forward.
To install the seat 1. Insert the projection on the rear of the seat into the seat holder as
shown.
2. Place the seat in the original posi- tion, and then tighten the bolts.
3. Install the panels.
TIPMake sure that the seat is properly se-
cured before riding.
EAU68420
A djustin g the shock a bsorb er
assem blies
WARNING
EWA10211
Always a djust both shock a bsor ber
assem blies equally, otherwise poor
han dlin g an d loss of sta bility may re-
sult.Each shock absorber assembly is
equipped with a spring preload adjust-
ing ring.NOTICE
ECA10102
To avoi d d amag ing the mechanism,
d o not attempt to turn b eyond the
maximum or minimum settin gs.Adjust the spring preload as follows.
To increase the spring preload and
thereby harden the suspension, turn
the adjusting ring on each shock ab-
sorber assembly in direction (a). To de-
crease the spring preload and thereby
soften the suspension, turn the adjust-
ing ring on each shock absorber as-
sembly in direction (b).
1. Bolt
1. Bolt
1
1
1. Projection
2. Seat holder
1
2
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Specifications
8-2
8
3rd:1.318 (29/22)
4th: 1.045 (23/22)
5th:
0.875 (21/24)
Chassis:Frame type:Diamond
Caster angle:
25.0 °
Trail: 82 mm (3.2 in)Front tire:Type:
Tubeless
Size: 2.75-18M/C 42P
Manufacturer/model: CHENG SHIN/C910Rear tire:Type:Tubeless
Size: 100/80-18M/C 59P
Manufacturer/model:
CHENG SHIN/C905Loading:Maximum load:171 kg (377 lb)
(Total weight of rider, passenger, cargo
and accessories)
Tire air pressure (measured on cold
tires):1 person:
Front: 175 kPa (1.75 kgf/cm², 25 psi)
Rear:
200 kPa (2.00 kgf/cm², 29 psi)
2 persons: Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear: 225 kPa (2.25 kgf/cm², 33 psi)
Maximum load: Front: 175 kPa (1.75 kgf/cm², 25 psi)
Rear: 250 kPa (2.50 kgf/cm², 36 psi)Front wheel:Wheel type:Cast wheel
Rim size: 18M/C x MT1.85Rear wheel:Wheel type:Cast wheel
Rim size: 18M/C x MT2.15Unified brake system:Operation:Activated by front brakeFront brake:Type:
Hydraulic single disc brake Specified brake fluid:
DOT 3 or 4
Rear brake:Type:
Mechanical leading trailing drum brakeFront suspension:Type:Telescopic fork
Spring:
Coil spring
Shock absorber: Hydraulic damper
Wheel travel: 120 mm (4.7 in)Rear suspension:Type:Swingarm
Spring: Coil spring
Shock absorber:
Hydraulic damper
Wheel travel: 112 mm (4.4 in)Electrical system:System voltage:
12 V
Ignition system: TCI
Charging system: AC magnetoBattery:Model:YTX5L-BS
UBT4E0E0.book Page 2 Wednesday, December 21, 2016 11:07 AM