Baja Comet 90cc BC90 User manual

Always wear a helmet; It could save your Life!
Do not remove this operator’s manual from this vehicle.
Please obtain, review, and follow provincial / municipal government acts and
regulations pertaining to owning and operating an off-road vehicle.
OWNER’S MANUAL
Model Number: BC90
Minimum Age Requirement: 16
Rev. A (US)
012709
Baja Comet 90cc Mini Bike
Read this manual carefully. It contains important safety information.
No one under the age of 16 should operate this Mini Bike .

ii
Congratulations on your purchase of the BAJA INC. Mini Bike.
Your Mini bike is warranted to be free of manufacturing defects in
material and workmanship for a period of 90 days from the date of
purchase. During the warranty period BAJA, INC. will at its option,
repair, provide replacement parts or replace your BAJA INC. Mini Bike
at no charge. This warranty does not cover normal wear items or
damage caused by neglect or misuse of the product.
Engine Warranty – 90 days
Frame Warranty – 90 days
Warranty is void if:
Frame is bent or broken due to abuse
Wheels are bent or broken
Fender bent or broken due to abuse
Any sign of impact, accident, jumping, spin-outs or roll over.
BAJA, INC. is not liable for any damage claim or liability claim person
or otherwise resulting from the operation of this product in any way.
Should you experience a problem with your vehicle, please call Baja Inc. customer
service line toll free at 1-888-863-2252 between the hours of 7am and 5pm Monday
through Friday MST (Mountain Standard Time). MDT (Mountain Daylight Time)
during the daylight saving time. You will be instructed how to proceed.
A COPY OF THE SALES RECEIPT IS REQUIRED.

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This manual should be considered as a permanent
part of the vehicle and should remain with the
vehicle when resold or otherwise transferred to
a new user or operator. The manual contains
important safety information and instructions
which should be read carefully before operating
the vehicle.
WARNING
The engine exhaust from this product contains
chemicals known to the State of California to cause
cancer, birth defects or other reproductive harm.
CALIFORNIA PROPOSITION 65
WARNING
!
!

1
NOTICE TO USERS.............................................................................................2
SAFE OPERATION..............................................................................................3
SAFETY GEAR....................................................................................................4
MODIFICATION OF VEHICLE.............................................................................4
PRE-RIDE CHECKLIST.......................................................................................5
MAIN DATA..........................................................................................................6
PARTS & SUBASSEMBLIES..............................................................................7
LOCATION OF WARNING LABELS ...................................................................9
OPERATION ........................................................................................................10
FUEL FILLING .............................................................................................10
ENGINE STARTING AND STOPPING.........................................................11
LEFT HANDLEBAR SWITCH......................................................................12
GEAR SHIFTING .........................................................................................13
CHECK-UPS, ADJUSTMENT AND MAINTENANCE..........................................14
CHANGING THE OIL...................................................................................14
CHECK-UP OF SPARK PLUG ....................................................................15
VALVE CLEARANCE...................................................................................16
CHECKING & CLEANING THE AIR FILTER...............................................17
ADJUSTING THE THROTTLE CABLE .......................................................18
ADJUSTING THE CARBURETOR ..............................................................18
ADJUSTMENT OF REAR AND FRONT BRAKE ........................................19
ADJUSTMENT OF CHAIN...........................................................................20
GREASING PROCEDURES TO THE DRIVING CHAIN..............................20
VEHICLE WASHING....................................................................................21
INSTRUCTIONS FOR STORAGE ...............................................................22
RESUMPTION OF SERVICE AFTER STORAGE .......................................23
TABLE AND TORQUE OF FASTENERS ....................................................23
MAINTENANCE ROUTINE DIAGRAM........................................................24
TROUBLE SHOOTING ................................................................................25
WIRE DIAGRAM ..........................................................................................26
VIN AND SERIAL NUMBER LOCATION.....................................................27
EMISSION CONTROL SYSTEM WARRANTY............................................28
Table of Contents

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Please read this manual and follow all instructions carefully. To emphasize the
special information, the symbol and the words WARNING or CAUTION have
some special meanings. Pay attention to the messages.
NOTE: Indicating special information which is to make maintenance easier or
instructions clearer.
WARNING and CAUTION are arranged like this:
This user’s manual contains important safety and maintenance information. Read
it carefully before riding. Failing to follow the warnings contained in this manual
could result in INJURY or DEATH.
It is important that this manual remain with the vehicle when you transfer it to
another user or owner.
All information, illustrations, photographs and specications contained in
this manual are based on the latest product information available at the time
of publication. Due to improvements or other changes, there will be some
discrepancies in this manual. We reserve the right to make product changes at
any time, without notice and without incurring any obligation to make the same or
similar changes to the vehicle previously built or sold.
WARNING-or-CAUTION
The rst part will identify a POTENTIAL HAZARD.
The second part will describe WHAT COULD HAPPEN if you ignore
the WARNING or CAUTION.
The third part will describe HOW TO AVOID THE HAZARD.
CAUTION
Indicates a potential hazard that could result in vehicle damage.
WARNING
Indicates a potential hazard that could result in death or injury.

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SAFE OPERATION
Rules for Safe Operation
· A pre-operation check must be conducted before starting engine to insure
safety, prevent mishaps, and prevent damage to components.
· It is strongly suggested that all operators take a certied motorcycle rider’s
course prior to operating the vehicle.
· Full attention is required during driving; paying close attention to the
following points to avoid any injury to you by other motorized vehicles:
· Do not drive too close to other vehicles.
· Never operate this mini bike at night. Night is dened as the period of time 30
minutes before sunset to 30 minutes after sunrise.
· Driving at high speeds is the cause of many accidents; do not drive at a speed
that the actual situation does not permit.
· This user’s manual contains important safety and maintenance information.
Read it carefully before riding. Failing to follow the warnings contained in this
manual could result in INJURY or DEATH.
· It is important that this manual remain with the vehicle when you transfer it to
another user or owner.
· All information, illustrations, photographs and specications contained in
this manual are based on the latest product information available at the time
of publication. Due to improvements or other changes, there will be some
discrepancies in this manual. We reserve the right to make product changes
at any time, without notice and without incurring any obligation to make the
same or similar changes to the vehicle previously built or sold
· Always avoid operating this mini bike on paved surfaces, including;
sidewalks, paths, parking lots, driveways, streets, roads, and highways.
Never operated this or any Off-Road Vehicle on a public street, road or
highway where motor vehicles are in operation.

4
SAFETY GEAR
1. Never operate this mini bike without wearing a DOT approved motorcycle
helmet which ts properly. Operators should also wear eye protection
(goggles or face shield), gloves, boots, long-sleeved shirt or jacket, and long
pants.
2. Loose clothes are not suitable for motorcycle driving or riding as they may
get caught on footrest or in moving parts.
MODIFICATION OF THE VEHICLE
CAUTION
Never perform any unauthorized modications to this vehicle. Only use
original replacement part which can be obtained through BAJA INC.
888-863-2252

5
Pre-Ride Checklist
Before Starting the Engine
1. Engine oil level
a) Check for leaks
b) Tighten filler cap securely.
c) Add oil if required.
2. Fuel level
a) Add fuel as necessary.
b) Do not overfill (no fuel in the filler neck).
c) Do not mix oil with gas.
d) Replace cap tightly.
e) Do not refuel a hot engine. Allow engine to cool before adding fuel.
3. Warning decals
a) Make sure all warning decals are legible and securely attached.
b) Replace as necessary.
4. Tires
a) Ensure that both tires are in safe riding condition.
b) Both tires must be inflated to the pressure indicated on the tire sidewalls.
5. Drive chain
a) Check condition and tension.
b) Lubricate and adjust tension as necessary.
6. Throttle
a) Check for smooth operation. Make sure the throttle “snaps” back to idle.
b) Check for frayed cable or damaged cable housing. Replace
damaged cable.
c) Check for mud, debris and ice in the throttle cable/mechanism. Clean out
any contamination.

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MAIN DATA
Description Data Description Data
Overall length 1539 mm
(60.61 in.)
Brake Type Drum
Overall width 669.8 mm
(26.37 in.)
Capacity of
gasoline tank
3L (.79 gal.) 87 octane or higher
unleaded gasoline
Overall height 959.6 mm
(37.78 in.)
Capacity of oil tank .24L (.25 qt.)
Wheelbase 1070 mm
(42.11 in.)
Displacement of
cylinder
86cc
Ground
clearance
189.7 mm
(7.47 in.)
Ignition means Magneto
Vehicle weight 67.59 kg
(149 lbs.)
Idling speed 1500 ± 100rpm.
Weight capacity 69.4 kg
(153 lbs)
Spark plug MEIYA - A7TC, NGK - C7HSA,
DENSO - U22FS-U, CHAMPION
- Z10YC
Front wheel 3.50 - 10
36psi
Spark plug gap 0.6-0.7mm
(.024”-.028”)
Rear wheel 3.50 - 10
36psi
Valve Clearance Intake 0.002 inch (0.05 mm)
Exhaust 0.003 inch (0.0762 mm)

7
PARTS & SUBASSEMBLIES
Brake lever
Throttle twist grip
Engine stop switch