Cobra CX65 2022 User manual

DISCLAIMER OF WARRANTY
This motorcycle is sold “as is” with all faults, obvious or not. There are no warranties
expressed or implied, including any warranty of merchantability and warranty of fitness for
any particular purpose.
“WARNING”
THE COBRA CX65 IS A COMPETITION MODEL ONLY AND IS NOT MANUFACTURED
FOR, NOR SHOULD IT BE USED ON PUBLIC STREETS, ROADS OR HIGHWAYS.
THE USE OF THIS BIKE SHOULD BE LIMITED TO PARTICIPATION IN SANCTIONED
COMPETITION EVENTS UPON A CLOSED COURSE BY A SUFFICIENTLY SKILLED
RIDER AND SHOULD NOT BE USED FOR GENERAL OFF-ROAD RECREATIONAL
RIDING.
IMPROPER USE OF THIS MOTORCYCLE CAN CAUSE INJURY OR DEATH.
THIS BIKE IS INTENDED FOR EXPERIENCED RACERS ONLY AND NOT FOR
BEGINNERS.
IT IS YOUR RESPONSIBILITY AS THE OWNER OF THIS COBRA MOTORCYCLE OR
AS THE PARENT, OR LEGAL GUARDIAN OF THE OPERATOR, TO KEEP THIS
COBRA MOTORCYCLE IN PROPER OPERATING CONDITION.
THIS BIKE WAS DESIGNED FOR RIDERS THAT WEIGH LESS THAN 110 LBS WITH
FULL RIDING GEAR AND SHOULD NOT BE OPERATED BY RIDERS THAT WEIGH
MORE THAN THAT.
BE SURE THAT THE RIDER ALWAYS WEARS ADEQUATE SAFETY GEAR
EVERYTIME HE OR SHE RIDES THEIR COBRA MOTORCYCLE.
IMPORTANT SAFETY NOTICE
Failure to follow WARNING instructions could result in severe injury or death to the
machine operator, a bystander, or a person inspecting or repairing the machine.
CAUTION:
A CAUTION indicates special precautions that must be taken to avoid damage to
the machine.
NOTE:
A NOTE provides key information to make procedures easier or clearer.
MCC62011.2

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Table of Contents
GENERAL INFORMATION ....................................................................................3
SPECIFICATIONS -GENERAL....................................................................................3
OPTIONAL COMPONENTS........................................................................................4
SPECIFICATIONS -TORQUE VALUES.........................................................................4
BREAK-IN PROCEDURE...........................................................................................5
STARTING PROCEDURE ..........................................................................................6
MAINTENANCE......................................................................................................7
TIPS......................................................................................................................7
SCHEDULE.............................................................................................................7
REPLACING TRANSMISSION /CLUTCH LUBRICANT.....................................................8
CHAIN ADJUSTMENT ...............................................................................................9
AIR FILTER CLEANING ..........................................................................................10
FORK OIL REPLACEMENT......................................................................................11
IGNITION TIMING...................................................................................................12
PARTS..................................................................................................................13
PARTS –AIRBOX &INLET SYSTEM.........................................................................13
PARTS –BARS AND CONTROLS.............................................................................14
PARTS -CARBURETOR .........................................................................................15
PARTS –COOLANT SYSTEM..................................................................................16
PARTS –ELECTRICAL SYSTEM ..............................................................................17
PARTS –ENGINE CLUTCH.....................................................................................18
PARTS –ENGINE –CLUTCH /KICK COVER.............................................................19
PARTS –ENGINE –IGNITION SIDE .........................................................................20
PARTS –ENGINE –KICK MECHANISM ....................................................................21
PARTS –ENGINE –SHIFT MECHANISM...................................................................22
PARTS –ENGINE –TOP END.................................................................................23
PARTS –ENGINE –TRANSMISSION ........................................................................24
PARTS –EXHAUST SYSTEM ..................................................................................25
PARTS –FORKS –LEG ASSEMBLY.........................................................................26
PARTS –FRAME &TRIPLE CLAMPS .......................................................................27
PARTS –FRONT WHEEL .......................................................................................28
PARTS –FRONT BRAKE........................................................................................29
PARTS –BODYWORK............................................................................................30
PARTS –REAR BRAKE..........................................................................................31
PARTS –REAR WHEEL .........................................................................................32
PARTS –SHOCK ..................................................................................................33
PARTS –SHOCK -INSIDE......................................................................................34
PARTS –SWINGARM ASSEMBLY ............................................................................35
SERVICE ..............................................................................................................36
ENGINE SERVICE .................................................................................................36
Base Gasket Selection...................................................................................37
FUEL &AIR SYSTEM.............................................................................................38
CARBURETOR:.....................................................................................................38
TUNING ................................................................................................................42

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GEARING.............................................................................................................42
SUSPENSION .......................................................................................................43
CARBURETION .....................................................................................................44
TROUBLESHOOTING..........................................................................................47
INDEX...................................................................................................................49

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General Information
Specifications - General
Items CX65
Dimensions
Wheelbase 40.9” (1040mm)
Wheel size 12” (305mm) rear, 14” (356mm) front
Seat height 29.9” (760mm)
Engine
Type 2-stroke, single cylinder, reed valve
Cooling system Liquid-cooled
Coolant 50/50 antifreeze-coolant / distilled water
Displacement 64.9 cc
Bore and stroke 43.0 mm x 44.7 mm
Ignition system Electronic, digital advance
Spark plug Champion 8339-1, 8332-1 hotter, 8904-1 colder
Gap 0.023” – 0.025” (0.58 – 0.64 mm)
Ignition timing Digital advance (set at “0” timing mark)
Fuel type High octane pump gasoline
Premix Oil type Motul 800 2T
Premix oil ratio after break-in
Motul 800 2T Off Road, 50:1 to 63:1
All other premix oil at 32:1 to 40:1
Carburetion 26 mm VM Mikuni
60Main Jet / Slow (Pilot) Jet 240 / 42.5
Needle 5I 14 - 4
Float Height 21.1 ± 1.0
Transmission 6 speed
Final drive ratio 14/45
Chain 116 links 420
Transmission / clutch oil type Quality gear lubricant, or Cobra clutch milk
Do Not Run Automotive Motor Oil
Quantity 530 ml (18.0oz)
Chassis
Front tire 60/100 – 14
Rear tire 80/100 – 12
Front fork Marzocchi 35mm USD, Compression adjustable
Fork oil type SAE 10 weight
Fork oil amount 210 ml (7.1oz)
Spring Preload Length 178mm (49 N/mm
Rear shock Compression Low 9 of 19 out, High 8 of 16 out
Rebound 26 of 29 clicks out, Race sag 87mm

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Optional Components
Call your dealer, or the factory, for details
Carburetor jets
Pre filter for the airbox
Tires, tubes or ‘Tire Balls’
Sprockets
Suspension Springs
Weight of Rider (lb) Fork Spring Shock Spring
less than 70 lb 0.24 kg/mm
KCC60024 42 N/MM (240 lb/in) SCC60240P (white)
75-85 lb 0.26 kg/mm
KCC60026 45 N/MM (260 lb/in) SCC60260PY stock
(y
ellow
)
85-100 lb 0.28 kg/mm
KCC60028 49 N/MM (280 lb/in) SCC60280PG (gold)
Greater than 100 53 N/MM (300 lb/in)
SCEX1300 (red)
Specifications - Torque Values
Fastener Torque Value Size & Remarks
ft-lb in-lb Nm
Cylinder head nuts 12.5 150 17 M7 x 1.0
Crankcase bolts 8.8 105 12 M6 x 1.0
Exhaust Flange 5 60 6 M6x1.0
Spark plug (SP) (SP) (SP) M14 x 1.25
Stator bolts 2.1 25 2.8 M5 X 0.8
Stator cover bolts 1.7 20 2.3 M4 X 0.75
Clutch cover bolts 5.8 70 7.9 M6 X 1.0
Clutch nut 35 420 47 M10 x 1.25*
Front axle bolt 10 120 13.5 M14 x 2.0
Front axle pinch bolt 7.4 88.5 10 M6 X 1.0
Engine mount bolts 22 265 30 M8 X 1.25
Swingarm Pivot 21 250 28 M12 X 1.5
Intake manifold bolts 4.6 55 6.2 M6 X 1.0
Rear Axle Bolt 25 300 34 M14 X 1. 5
Rear Sprocket Bolts 20 240 27 M8 X 1.25
Triple clamp (top) 9 108 12 M6 x 1.0
Triple clamp (bottom) 6 72 8 M6 x 1.0
Fork cap 15 177 20
Fork Damper Nut 11 133 15
Ignition rotor nut 33 400 45 M10 x 1.25*
* Apply high strength thread locking agent when installing
(SP) To apply the proper torque to the spark plug when inserting, one must first
screw the spark plug in until the metal gasket ring causes resistance and then turn
another 1/8 to ¼ turn.

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Break-In Procedure
Your Cobra CX65 is a close-tolerance high performance machine and break-in
time is very important for maximum life and performance. The CX65 can be ridden
hard after the first ½ hour break-in time.
Cobra recommends Motul 800 T2 premix oil with high octane
pump gas mixed at 50:1 (50 ml oil to 1.3 gallon of gas, or 38ml oil to 1 gallon of
gas). Other brands of oil should be mixed at 32:1 for break-in.
CAUTION:
Failure to use proper fuel, oil, or fuel/oil mixture may result in premature engine
wear or damage to the machine.
Adhering to the following break-in schedule will result in long lasting high
performance machine.
Start bike on stand
First 5 minute period, operate the bike on the stand with a combination of idle
and high RPM operation. (avoid prolonged high RPM but spin the rear wheel
good at least once or twice per minute)
Allow bike to cool
Ride for 15 minutes maximum (avoid prolonged high RPM operation and avoid
abusing the clutch).
Cool and inspect bike for loose fasteners.
Check & retighten wheel spokes
Next ½ hour of operation, avoid prolonged operation at Wide Open Throttle.
After 1 hour of operation
oCheck for loose bolts and nuts on the bike and retighten as necessary
(proper toque values are listed under Specifications).
oClean the carburetor bowl.
oChange the transmission / clutch lubricant.
After 8 hours of operation
oChange the fork oil.
oHave a Certified Cobra Mechanic change the shock oil.
Your bike is now ready for the highest level of competition!
NOTE:
During break-in the bike will likely lose some engine coolant through the radiator
overflow hose. Losing up to 4 oz (120 ml, ½ cup) is normal. Proper coolant level
will cover the top of the radiator cores. Removing the radiator cap and looking
inside is the only way to check the coolant level.
Never open the radiator cap of a machine that has a hot or warm engine or one
that has recently been ridden. Burning and scalding could occur.

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CAUTION:
It is important that the radiator cap is installed correctly and completely otherwise
engine damage could occur.
Starting Procedure
Before starting the machine inspect the following:
Check for proper tire pressure in both tires.
Observe the chain tension and adjust if necessary.
Observe the coolant level and fill if necessary.
Verify that the chain rollers and sliders do not have improper wear.
Verify that the handlebars are tight.
Check the throttle for smooth operation and sound closing.
Check for loose bolts and nuts, and re-torque as necessary.
Verify that the air filter is clean and properly saturated with oil.
Insure that the fuel tank contains an adequate volume of fuel / oil mixture to
complete the distance required. (High octane pump gas with Cobra’s specially
formulated Cobra Venom 2-cycle Race Oil)
Turn the fuel on by rotating the fuel petcock lever to the vertically downward
position.
CAUTION:
For best results from your Cobra Motorcycle use only the recommended fuels.
‘Race’ fuels can be used, however, they are not required with the stock engine,
and the engine will require addition attention to maintain proper jetting as weather
condition change throughout the day.
Always wear a helmet and other protective riding gear.
When your pre-ride inspection is complete the bike may be started. For a cold
engine follow this procedure.
1. Place the motorcycle on a stand of sufficient strength that positions the
motorcycle in a level upright position with the rear wheel off the ground.
2. Engage the choke by pulling out on the choke button until it stops.
3. Kick start the engine.
4. Rev the engine in short spurts, turning the throttle no more than 1/4 open until
the engine will run without the choke.
5. Verify a functional engine shut-off switch by shutting off the engine.
6. Restart the engine and proceed with riding when the engine is sufficiently
warm (i.e. the side of the cylinder is warm to touch).
CAUTION:
Never rev an engine full throttle when it's cold or slightly warmed up. This may lead
to premature wear of engine components or complete cold seizure of the engine.

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CAUTION:
Cobra recommends that you tell your child to take it easy the first couple of
minutes in practice until the engine comes up to full operating temperature.
Maintenance
It is important that you adhere to this maintenance schedule so as to promote the
longevity of your Cobra Motorcycle.
Tips
1. Cobra lubricants:
a. Use only high quality transmission oil designed specifically for two-
stroke racing engines.
b. Motul 800 2T Off Road oil is the recommended premix oil because:
Its Ester base leaves a film on all parts at all times. No metal
to metal startups or corrosion potential.
Exception film strength over petroleum based oils or synthetic
blends.
Easily atomizes and burns completely.
Does not fall out of suspension from premix in cold weather.
Produces virtually no coking deposits, leaving pistons, rings
and heads extremely clean with minimal pipe ‘spooge’.
2. Fill your transmission only with the recommended amount of oil. Overfilling
may lead to premature seal failure.
3. The cylinder base gasket has been ‘fitted’ for your engine. See the service
section of this manual for instructions how to properly size a base gasket
during an engine rebuild.
4. Evaluate the bikes jetting only after it has been warmed up to race
temperatures.
5. A properly maintained machine is safer, faster, and more fun to ride.
6. New chains will stretch on first use. Never install a new chain prior to a race.
Always ‘break’ them in during practice.
7. Your Cobra Motorcycle has a 10 digit VIN (Vehicle Identification Number).
The first two digits indicate the model and the seventh indicates the model
year (MY).
a. Example, CXxxxx7xxx is a 2007 MY CX65.
Schedule
Between each ride
oCheck the air filter (clean and re-oil as necessary).
oInsure the smooth operation of the throttle cable (throttle soundly ‘clacks’
shut).
oCheck for frayed strands of the throttle cable inside the throttle housing
and replace if necessary.
oCheck for adequate tire pressures and adjust if necessary.
oCheck all nuts and bolts for proper torque and re-torque if necessary.
oSpray all moving parts with WD40 or other water displacing oil.
oCheck drive chain for

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Proper tension and adjust if necessary.
Adequate lubrication and lubricate if necessary.
oInsure that the ignition stator and rotor are clean and dry.
oCheck the frame for cracks in the metal or cracks in the paint that might
indicate that the metal has been stressed beyond it’s safe limits.
Replace or get properly re-welded as necessary.
oCheck the spokes for tightness and adjust if necessary.
oCheck the rims and hubs for signs of stress, like cracks around the rim,
spokes and hub.
Every 2 hours of operation
oReplace the transmission oil.
oCheck spoke tension
Every 10 hours of operation
oReplace the fork oil.
oHave the shock oil replaced by a Certified Cobra Mechanic.
CAUTION:
If you ever need to weld anything on the bike, disconnect the spark plug cap,
unplug the ignition, disconnect the kill switch, scrape the paint bare near the area
to be welded and put the ground clamp as close to the area to be welded as
possible.
Be sure the fuel tank and carburetor have been removed and safely located away
from the welding process.
The frame is a combination of HSLA steel and 4130 Chrome Moly and it is
important to weld it with the proper rod and heat settings set as light as possible.
Cobra recommends replacing the frame with a new one if the old one becomes
damaged. Use ER70S6 filler if welding on the frame.
Replacing Transmission / Clutch Lubricant
Tools needed:
18 oz, of high quality transmission oil, or Cobra clutch milk
8 mm Allen wrench
CAUTION:
General automotive motor oil has frictional modifiers which will cause premature
wear and failure of the clutch.
Procedure:
1. Begin this procedure with a bike that has been ridden more than 5 minutes but
less than 10 minutes. It is desired to have the engine warm enough so that the
oil is ‘runny’ but not so hot that there is risk of being burned by the engine or the
oil.

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Hot oil and hot components on the motorcycle may cause burns.
2. Lean the bike against something or set on stand with oil drain hole.
3. Using a 8mm Allen wrench, remove the oil drain bolt located on the right side of
the engine, on the clutch cover, near the brake lever (See Figure 1).
NOTE: You may need to adjust the brake pedal (up or down) to gain access to the
drain bolt.
4. After it has drained, reinstall the
bolt being sure that the rubber
gasket is in place. Torque to 11
Nm (8 ft-lb).
5. Remove oil fill plug with an 8mm
Allen wrench.
6. Carefully pour 16 oz (470 ml) of
transmission oil into the oil fill
opening.
7. Reinstall the oil fill plug making
sure the rubber gasket is in
place.
NOTE: Filling after an engine rebuild required additional transmission fluid. If the
engine is completely flushed of oil, refill with 18 oz (530ml).
Always capture and dispose of used oil properly (all auto parts stores accept used
oil). Dumping oil on the ground is illegal, inconsiderate, and can get you
disqualified from a race weekend quicker than cutting the track.
Chain adjustment
Tools required for chain adjustment
22 mm wrench or socket
2 - 11 mm open-end wrenches
1. Make sure that the rear wheel is
aligned properly.
2. For proper adjustment, the chain
should have 35 mm free movement
just behind the chain block with no
load on the bike (Figure 2)
CAUTION:
Sit on the bike and verify that the chain
has a minimum of 12mm (1/2”) free
movement when the chain is at its
tightest point.
Figure 1
Figure 2