Yamaha YP250D 98 Manual

FOREWORD
This Supplementary Service Manual has been prepared to introduce new service and data for the
YP250D ’98. For complete service information procedures it is necessary to use this Supplementary
Service Manual together with the following manual.
YP250 SERVICE MANUAL: 4UC-AE1
YP250 (J) SUPPLEMENTARY SERVICE MANUAL: 4UC-AE2
YP250D ’98
SUPPLEMENTARY
SERVICE MANUAL
1997 by Yamaha Motor Co., Ltd.
First Edition, December 1997
Any reproduction or unauthorized use
without the written permission of
Yamaha Motor Co., Ltd.
is expressly prohibited.

NOTE:
CAUTION:
EB001000 NOTICE
This manual was produced by the Yamaha Motor Company primarily for use by Yamaha dealers and
their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual,
so it is assumed that anyone who uses this book to perform maintenance and repairs on Yamaha
scooter has a basic understanding of the mechanical ideas and the procedures of scooter repair. Re-
pairs attempted by anyone without this knowledge are likely to render the scooter unsafe and unfit for
use.
YamahaMotorCompany,Ltd.iscontinuallystrivingtoimproveallitsmodels.Modificationsandsignifi-
cant changes in specifications or procedures will be forwarded to all authorized Yamaha dealers and
will appear in future editions of this manual where applicable.
Designs and specifications are subject to change without notice.
IMPORTANT INFORMATION
Particularly important information is distinguished in this manual by the following notations.
The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED!
FailuretofollowWARNINGinstructionscouldresultinsevereinjuryordeathto
thescooter operator, abystander ora personinspectingorrepairingthescoot-
er.
ACAUTION indicatesspecialprecautionsthatmust betakentoavoiddamage
to the scooter.
NOTE: A NOTE provides key information to make procedures easier or clearer.

1
243
5
6
7
6
8
YP002000 HOW TO USE THIS MANUAL
MANUAL ORGANIZATION
This manual consists of chapters for the main categories of subjects. (See “Illustrated symbols”)
1st title 1: This is the title of the chapter with its symbol on the upper right corner of each page.
2nd title 2: This title indicates the section of the chapter and only appears on the first page of each
section. It is located in the upper left corner of the page.
3rd title 3: This title indicates a sub-section that is followed by step-by-step procedures accompa-
nied by corresponding illustrations.
EXPLODED DIAGRAMS
Tohepsidentifypartsandclarifyproceduresteps,thereareexplodeddiagramsatstartofeachremov-
al and disassembly section.
1. An easy-to-see exploded diagram 4is provided for disassembly and assembly jobs.
2. Numbers 5aregivenintheorderofjobs intheexplodeddiagram.Anumberthatisenclosedbya
circle indicates a disassembly step.
3. An explanation of jobs and notes is presented in an easy-to-read way by the use of symbol marks
6. The meanings of the symbol marks are given on the next page.
4. A job instruction chart 7accompanies the exploded diagram, providing the order of jobs, names
of parts, notes in jobs, etc.
5. Forjobsrequiring more information,thestep-by-step format supplements 8aregiven inaddition
to the exploded diagram and the job instruction chart.

1
3
5
7
9
11
13
15
18
2
4
8
10
12
14
16
6
21
24 25
17
19 20
22 23
EB003000
ILLUSTRATED SYMBOLS
Illustrated symbols 1to 9are designed as
thumb tabs to indicate the chapter’s number
and content.
1General information
2Specifications
3Periodic inspection and adjustment
4Engine
5Cooling system
6Carburetion
7Chassis
8Electrical
9Troubleshooting
Illustrated symbols 10 to 17 are used to identify
the specifications appearing in the text.
10 Possible to maintain with engine mounted
11 Filling fluid
12 Lubricant
13 Special tool
14 Tightening
15 Wear limit, clearance
16 Engine speed
17 Ω, V, A
Illustratedsymbols 18 to 23 in theexplodeddia-
grams indicate the types of lubricants and lu-
brication points.
18 Apply engine oil
19 Apply gear oil
20 Apply molybdenum disulfide oil
21 Apply wheel bearing grease
22 Apply lightweight lithium-soap base grease
23 Apply molybdenum disulfide grease
Illustratedsymbols 24 to 25 in theexplodeddia-
gramsindicatethewheretoapplylockingagent
24 and when to install new parts 25 .
24 Apply locking agent (LOCTITE)
25 Use new one

CONTENTS
SPECIFICATIONS 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL SPECIFICATIONS 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE SPECIFICATIONS 2. . . . . . . . . . . . . . . . . . . . . . . . . . .
ENGINE 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHASSIS 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ELECTRICAL 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CABLE ROUTING 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PERIODIC INSPECTION AND ADJUSTMENTS 10. . . . . . . . . . . . . . . . . . .
INTRODUCTION 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PERIODIC MAINTENANCE/LUBRICATION INTERVALS 10. . . . . . . . .
COVER AND PANEL 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SIDE PANEL AND SEAT 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ADJUSTING THE REAR BRAKE 13. . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE REAR BRAKE FLUID 13. . . . . . . . . . . . . . . . . . . . . .
CHECKING THE REAR BRAKE PADS 14. . . . . . . . . . . . . . . . . . . . . .
BLEEDING THE HYDRAULIC BRAKE SYSTEM 14. . . . . . . . . . . . . .
ADJUSTING THE REAR SHOCK ABSORBER ASSEMBLIES 16. .
CHASSIS 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REAR WHEEL AND BRAKE DISC 17. . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE BRAKE DISC 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REAR BRAKE 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BRAKE PAD 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REPLACING THE BRAKE PADS 20. . . . . . . . . . . . . . . . . . . . . . . . . . .
CALIPER 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CALIPER DISASSEMBLY 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE REAR BRAKE CALIPER 23. . . . . . . . . . . . . . . . . .
MASTER CYLINDER 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MASTER CYLINDER DISASSEMBLY 25. . . . . . . . . . . . . . . . . . . . . . .
REAR SHOCK ABSORBER AND SWINGARM 26. . . . . . . . . . . . . . . . .

1
GENERAL SPECIFICATIONS SPEC
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model YP250D
Model code: 5DF1 (except for CH, A, AUS)
5DF2 (for CH, A)
Basic weight:
With oil and full fuel tank 164 kg
Transmission:
Primary reduction system
Primary reduction ratio
Secondary reduction system
Secondary reduction ratio
Transmission type
Operation
Single speed automatic
Helical gear
38/15 (2.533)
Sper gear
37/16 (2.312)
Single speed automatic (V-belt type)
Centrifugal automatic type
2.34 0.82 : 1
Tire pressure (cold tire):
Maximum load-except motorcycle
Loading condition A*
front
rear
Loading condition B*
front
rear
High-speed riding
front
rear
191 kg
0 90 kg
175 kPa (1.75 kg/cm2, 1.75 bar)
200 kPa (2.0 kg/cm2, 2.0 bar)
90 191 kg
200 kPa (2.0 kg/cm2, 2.0 bar)
225 kPa (2.25 kg/cm2, 2.25 bar)
200 kPa (2.0 kg/cm2, 2.0 bar)
250 kPa (2.5 kg/cm2, 2.5 bar)
Brake:
Front brake type
operation
Rear brake type
operation
Single disc brake
Right hand operation
Single disc brake
Left hand operation
Wheel travel:
Front wheel travel
Rear wheel travel 85 mm
90 mm
Electrical:
Ignition system
Generator system
Battery type
Battery capacity
T.C.I. (Digital)
A.C. magneto
GT7B-4
12 V 6.5 AH
*Load is the total weight of cargo, rider, passenger, and accessories.

2
MAINTENANCE SPECIFICATIONS SPEC
MAINTENANCE SPECIFICATIONS
ENGINE
Item Standard Limit
Automatic centrifugal clutch:
Clutch shoe thickness
Clutch housing inside diameter
Clutch shoe spring free length
Weight outside diameter
Clutch - in revolution
Clutch - stall revolution
3.0 mm
135 mm
28.1 mm
20 mm
2,250 2,850 r/min
3,700 4,700 r/min
2.0 mm
135.5 mm

19.5 mm


Carburetor:
Type
I.D. mark
Ventuly outside diameter
Main jet (M.J)
Main air jet (M.A.J)
Jet needle (J.N)
Throttle valve size (Th.V)
Pilot air jet (P.A.J.1)
Needle jet (N.J)
Pilot outlet (P.O)
Pilot jet (P.J)
Bypass (B.P)
Pilot screw (P.S)
Valve seat size (V.S)
Starter jet 1 (G.S.1)
Starter jet 2 (G.S.2)
Float height (F.H)
Engine idle speed
Intake vacuum
Oil temperature
Cooling water temperature
Y28V-1A
4UC 02 [4UD 00 (CH)]
ø28
#130
ø0.9
5D32-3/5
11
ø1.2
#85
ø0.8
#44
0.7 3
1 7/8 [1 5/8 (CH)]
1.4
ø0.45 [ø0.47 (CH)]
ø0.5
27 mm
1,350 1,450 r/min
220 260 mmHg
65 75C
80C




















CHASSIS
Item Standard Limit
Front suspension:
Front fork travel
Fork spring free length
Spring rate (K1)
Stroke (K1)
Oil capacity
Oil level
Oil grade
Inner tube vend limit
100 mm
268.5 mm
5.7 N/mm (0.57 kg/mm)
0 100 mm
0.142 L (142 cm3)
80 mm
Fork oil 15 WT or equivalent


263.5 mm





0.2 mm

3
MAINTENANCE SPECIFICATIONS SPEC
Item Standard Limit
Rear disc brake:
Type
Disc outside diameter xthickness
Pad thickness
Master cylinder inside diameter
Caliper cylinder outside diameter
Brake fluid type
Single
230 x5.3 mm
5.3 mm
11 mm
22.2 + 22.2 mm
DOT #4


0.8 mm



ELECTRICAL
Item Standard limit
T.C.I.:
Pickup coil resistance/color
T.C.I. unit model/manufacturer
189 231 Ωat 20_C
Yellow – Green
J4T091/MITSUBISHI



4
D C B A
Left Right Right
Left
Front
Front
Left
Right
Front
Right
Left
9090
CABLE ROUTING SPEC
1Fuel tank cap over flow hose
2Throttle cable (pull side)
3Throttle cable (return side)
4Carburetor fuel drain hose
5Carburetor coolant drain hose
6Carburetor air ventilation
hose
7Stay
8Steering head pipe
9Rear brake hose
10 Down tube
11 Throttle cable
12 Wireharness
A Pass the rear brake hose
through the handlebar holder.
B Use a plastic band to fasten
the rear brake cable to the
steering head pipe.
C Use a plastic band to fasten
the throttle cable and
wireharness to the frame.
D Pass the rear brake hose
through the frame guide,
then use a plastic band
to fasten them to frame.
E Pass the carburetor air
ventilation hose, coolant drain
hose and carburetor fuel drain
hose through the plastic
U-clamp.
F Pass the carburetor fuel
drain hose through the frame
holder.
G Pass the fuel tank cap flow
hose though the frame holder.
CABLE ROUTING

5
D C B A
Left Right Right
Left

Front
Left
Right
Front
Right
Left 90
90
H Pass the fuel tank over flow
hose through inside of the
frame clamp.
I Use a plastic band to fasten
the throttle cable to frame.
J Use a plastic band to fasten
the wireharness to the
headlight stay.
K Locate the band end as
illustration.
CABLE ROUTING SPEC

6
D
Front
C B A-A
A Connect the taillight lead
connector on the mud guard.
B Use a plastic clamp to fasten
the fuel sender lead to the
pipe.
C Use a steel clamp to fasten the
fuel sender lead and auto
choke lead.
D Pass the box switch lead
through under the fuel tank
hinge projection.
E Align the mark on seat lock
cable to the protector end.
F Use a plastic band to fasten
the wireharness and seat lock
cable.
13 Reservoir tank
14 Fuel tank breather hose
15 Air filter
16 Mud guard
17 Down tube
18 Wireharness
19 Engine bracket
20 Engine ground lead
21 AC magnet lead
22 Starter motor lead
23 Rear brake hose
1Box light
2Rectifire regulator
3Fuel sender
4Roll over valve
5Fuse
6Battery negative (–) lead
7Seat lock cable
8Handlebar switch lead (right)
9Front brake switch lead
10 Starter switch
11 Battery positive (+) lead
12 Flasher relay
CABLE ROUTING SPEC

7
D
Front
C B A-A
G Align white tape on the
wireharness to the clamp,
then fasten it.
H Pass the reservoir tank over
flow hose through the clamp
inside of the frame.
I Pass the rear brake hose,
wireharness, battery (+)/(–)
leads through the guide.
J Use a steel band to fasten the
wireharness, battery (+)/(–)
leads.
K Locate the band end as
illustration.
CABLE ROUTING SPEC

8
Upper
D A-AB
B
13 Fuel cock
14 Fuel tank
15 Rear trun signal light cover
16 Rear turn signal light lead
CABLE ROUTING SPEC
1Fuel tank breather hose
2Fuel hose
3Vacuum hose
4Fan motor lead
5Fuel tank over flow hose
6Reservoir tank over flow hose
7Starting circuit cut-off relay
8Auto choke lead
9AC magneto lead
10 Starter motor lead
11 Engine ground lead
12 Seat lock cable
A Use a steel clamp on the frame
to fasten the sidestand lead.
B Pass the thermo switch lead
through outside of frame.
C Use a clamp on the frame to
fasten the sidestand switch
lead and battery positive (+)
lead.
D Use a steel clamp on behind
of the frame to fasten the
wireharness, AC magneto
lead, starter motor lead and
engine ground lead.

9
13 Rear brake switch lead
14 Handlebar under cover
CABLE ROUTING SPEC
1Front turn signal light (right)
2Front turn signal light (left)
3Rear brake hose
4Throttle cable
5Speedometer cable
6Front brake hose
7Headlight stay
8Grip warmer lead
9Handlebar switch lead (right)
10 Front brake switch lead
11 Seat lock cable
12 Handlebar switch lead (left)
A Pass the speedometer cable
and front brake hose through
the holder.
B Use a steel clamp on headlight
stay to fasten the headlight
lead and horn lead.
C Do not interfere each other
after installing the handleber
upper cover.

10
INTRODUCTION/
PERIODIC MAINTENANCE/LUBRICATION INTERVALS INSP
ADJ
EB300000 PERIODIC INSPECTIONS AND ADJUSTMENTS
INTRODUCTION
This chapter includes all information necessary to perform recommended inspections and
adjustments.Thesepreventive maintenanceprocedures, iffollowed,will ensuremorereliablevehicle
operation and a longer service life. The need for costly overhaul work will be greatly reduced. This
informationappliestovehiclesalreadyinserviceaswellastonewvehiclesthatarebeingpreparedfor
sale. All service technicians should be familiar with this entire chapter.
PERIODIC MAINTENANCE/LUBRICATION INTERVALS
EVERY
No. ITEM CHECKS AND MAINTENANCE JOBS Intial
(1,000 km)
6,000 km
or
6 months
(Whichever
comes first)
12,000 km
or
12 months
(Whichever
comes first)
1 * Fuel line Check fuel hoses and vacuum hose for cracks or damage.
Replace if necessary. √ √
2Spark plug Check condition.
Clean, regap or replace if necessary. √ √ √
3 * Valves Check valve clearance.
Adjust if necessary √
4Air filter Clean or replace if necessary. √ √
5V-belt case air filter Clean or replace if necessary. √ √
6 * Front brake
Check operation, fluid level and vehicle for fluid leakage.
(See NOTE)
Correct accordingly.
Replace brake pads if necessary
√ √ √
7 * Rear brake
Check operation, fluid level and vehicle for fluid leakage.
(See NOTE)
Correct accordingly.
Replace brake pads if necessary.
√ √ √
8 * Wheels Check balance, runout and for damage.
Rebalance or replace if necessary. √ √
9 * Tires
Check tread depth and for damage.
Replace if necessary.
Check air pressure.
Correct if necessary.
√ √
10 * Wheel bearings Check bearing for looseness damage.
Replace if necessary. √ √
11 *Steering bearings
Check bearing play and steering for roughness.
Correct accordingly.
Lubricate with lithium soap base grease every 24,000 km or
24 months (whichever comes first).
√ √
12 * Chassis fasteners Make sure that all nuts, bolts and screws are properly tightened.
Tighten if necessary. √ √ √
13 Sidestand/centerstand Check operation.
Lubricate and repair if necessary. √ √ √
14 * Sidestand switch Check operation.
Replace if necessary. √ √ √
15 * Front fork Check operation and for oil leakage.
Correct accordingly √ √
16 * Rear shock absorber
assemblies
Check operation and shock absorbers for oil leakage.
Replace shock absorber assembly if necessary. √ √
17 * Carburetor Check engine idling speed and starter operation.
Adjust if necessary. √ √ √
18 Engine oil
Check oil level and vehicle for oil leakage.
Correct if necessary.
Change. (Warm engine before draining) √Replace every 3,000 km
19 *Engine oil strainer Clean or replace if necessary. √Clean or replace every
3,000 km
20 *Cooling system
Check coolant level and vehicle for coolant leakage.
Correct if necessary.
Change coolant every 24,000 km or 24 months
(whichever comes first).
√ √

11
PERIODIC MAINTENANCE/LUBRICATION INTERVALS INSP
ADJ
NOTE:
EVERY
No. ITEM CHECKS AND MAINTENANCE JOBS Intial
(1,000 km)
6,000 km
or
6 months
(Whichever
comes first)
12,000 km
or
12 months
(Whichever
comes first)
21 Final gear oil DCheck oil level and vehicle for oil leakage.
DChange oil at initial 1,000 km and thereafter every 10,000 km. √Replace every 10,000 km
*: Since these items require special tools, data and technical skills, they should be serviced by a Yamaha dealer.
EAU00477
SThe air filter needs more frequent service if you are riding in unusually wet or dusty areas.
SBrake fluid replacement
1. When disassembling the master cylinder or caliper cylinder, always replace the brake fluid.
Check the brake fluid level regularly and fill as required.
2. Replace the oil seals on the inner parts of the master cylinder and caliper cylinder every two
years.
3. Replace the brake hoses every four years or if cracked or damaged.

12
Install the damper assembly to the body
with its rod side backward and labels up-
ward.
Reverse the removal procedure for
installation.
Order Job name/Part name Q’ty Remarks
1
2
3
4
5
6
7
8
Side panel and seat removal
Rear panel
Side panel (left)
Side panel (right)
Rivet
Front panel
Clip
Damper assembly
Seat
1
1
1
2
1
2
1
1
Remove the parts in order.
NOTE:
COVER AND PANEL INSP
ADJ
COVER AND PANEL
SIDE PANEL AND SEAT