Cobra 2003 CH2, Owner'S Service Manual

Page 1: ...2003 PW3 Owners Service Manual CHAMPIONS START HERE ...

Page 2: ... Cobra dealer log on to www cobramotorcycle com or call 330 549 9600 If you need technical assistance contact your local dealer or call the Cobra Technical Support Hotline at 330 549 9603 Cobra Motorcycle MFG Inc 11511 Springfield Road North Lima Ohio 44452 MCPW2003 4 ...

Page 3: ...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 80 LBS WITH FULL RIDING GEAR AND SHOULD NOT BE OPERATED BY RIDERS THAT WEIGH MORE THAT BE SURE THAT THE RIDER A...

Page 4: ...ssion Clutch Lubricant 11 M2 Chain adjustment 12 M3 Front brake adjustment 13 M4 Rear brake adjustment 14 M5 Air Filter Cleaning 14 M6 Fork Oil Replacement 15 M7 Clutch Adjustment 16 Engine Service Parts 17 ES1 Top End Parts 18 ES2 Bottom end transmission 19 ES3 Clutch 22 ES4 Ignition 23 ES5 Cooling System 24 ES6 Fuel Air System 25 ES7 Exhaust 30 Chassis Service Parts 30 CS1 Wheels Tires 30 CS2 Su...

Page 5: ...park plug Champion C53 NGK B11EGV Gap 0 023 0 025 0 58 0 64 mm Fuel type Sunoco MO2X or 93 octane pump gasoline OTHER RACE FUELS ARE NOT RECOMMENDED Injector oil type Cobra Venom 2 cycle Race Oil Fuel oil mix ratios Fill oil reservoir as required Ignition timing Fixed Carburetion 12 mm Dell Orto PHVA PS Main jet 82 Slow Pilot jet 42 Float height 5 mm 0 3mm 0 2 0 012 Transmission Speed Single Clutc...

Page 6: ...l height 70 mm 2 75 collapsed from top with spring no spacer Specifications Torque Values Torque Value Fastener ft lb in lb Nm Size Remarks Front engine mount bolts 22 264 30 8 x 1 25 Rear engine mount bolts 22 264 30 8 x 1 25 Swingarm pivot bolt 21 250 28 14 x 2 Rear sprocket bolts 18 216 24 7 x 1 Rear axle bolts 25 300 34 12 x 1 25 Rear shock mounts 40 480 54 10 x 1 5 Clutch adjust access plug 1...

Page 7: ...r lb Fork Spring Shock Spring Less than 38 light KCMZ0012A SCMU0321 yellow 320 lb in 38 45 std KCMZ0012 SCMU1360 red 260 lb in 46 to 55 stiff KCMZ0012B SCMU1380 white 380 lb in Extra stiff SCMU1400 silver 400 lb in Suspension Valving Damping Rate Fork Valving Compression right Fork Valving Rebound left Shock Valving kit Soft fast KCMZ0033A KCMZ0032A SCMU0318A Standard KCMZ0033 KCMZ0032 SCMU0318 Ha...

Page 8: ...bra s specially formulated Cobra Venom 2 cycle Race Oil Part MCMUOL02 CAUTION Failure to use proper fuel or oil 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 First hour of operation o Follow the starting procedure listed in this manual o Avoid prolonged operation at Wide Open Throttle Af...

Page 9: ...position is horizontally forward CAUTION For best results from your Cobra Motorcycle use only the recommended fuels Testing has shown that most race fuels actually degrade performance 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 posi...

Page 10: ...e they are riding 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 When washing the bike be careful to not directly aim the hose at the bottom edge of the seat or water is apt to enter the airbox 7 Your Cobra Motorcycle has a 10 digit VIN Vehicle Identification Number The first two digits indic...

Page 11: ...r tension and adjust if necessary Adequate lubrication and lubricate if necessary o Insure that the ignition stator and rotor are clean and dry o Check 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 rewelded as necessary o Fill the 2 stroke injector oil reservoir with Cobra s specially fo...

Page 12: ...ilk Part MCMUGF01 or Dexron III Automatic Transmission Fluid 3 Phillips screwdriver large flat blade screwdriver or coin 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 runny but not so hot that there is risk of being burned by the engine or the oil Hot oil and hot components...

Page 13: ... proper lubrication to handle the harsh environment of the automatic clutch and transmission of this motorcycle Cobra was forced to put forth this effort because the other available options and not adequate Cobra s specially developed Cobra Venom 3 Shoe Clutch Milk Part MCMUGF01 is the recommended lubricant for your PW3 motorcycle M2 Chain adjustment Tools required for chain adjustment Two 19 mm w...

Page 14: ...nded for front brake maintenance 10mm open end wrench From the brake lever 1 Loosen the locking nut on the brake lever 2 Adjust the bolt to desirable position 3 Tighten the locking nut From the brake hub 1 Loosen the 10mm nut on the hub 2 Adjust the brake cable to desirable position 3 Tighten the 10mm nut CAUTION If you tighten the front brake up too much the brakes may hang up causing the brake p...

Page 15: ...ngaged If so the brake pads will burn up and need replaced M5 Air Filter Cleaning Tools recommended for air filter maintenance 2 Phillips head screwdriver 4 mm hex key Allen Foam filter oil Procedure 1 Removed the seat with the 4 mm hex key 2 Remove the two Phillips head screws holding the filter to the entrance of the airbox 3 Clean the filter in a nonflammable solvent to remove the filter oil 4 ...

Page 16: ...t Tools required 5 6 mm Allen wrench 19 mm wrench or socket two required Spring clip remover Disassembly 1 Remove the front wheel 2 Remove the fork legs from the triple clamps 3 Perform the following on one leg at a time 4 Using your hands remove the black rubber plug from the top of the fork leg exposing the white plastic cap 5 Secure the fork leg assembly in a vice by gripping the leg across the...

Page 17: ...rge flat head screws is visible through the access hole this flat head screw is one of the three adjusters NOTE Turning the adjusting screw Counter Clock Wise CCW will allow the shoe to engage at a lower RPM this is the direction you should adjust to compensate for shoe wear Alternatively a Clock Wise CW adjustment of the screw will allow the clutch to engage at a higher RPM 3 Subsequently use the...

Page 18: ...u don t feel comfortable with the service work simply take your engine out of the frame and sent it to Cobra Precision Engines 11511 Springfield Road North Lima Ohio 44452 Cobra s technicians will go through the entire engine replacing gaskets bolts any old part that is worn The engine will be rebuilt using the same precision gauging and assembly fixtures as when it was assembled new Before leavin...

Page 19: ...SINGLE RING 3 HCBC0603 6X30 CAP SCREW 4 HCNF0601 FLANGED NUT 6MM 5 ECMOTE05 CYLINDER HEAD 6 ZCMOTE06 CYLINDER HEAD O RING 7 ECMU0026 6MM DOWEL 9 ECMOTE09 CYLINDER HEAD STUD BOLT 6MM 10 ZCMOTE10 BASE GASKET 11 ZCMOTE11 O RING EXHAUST FLANGE 12 ECMU0056 PISTON RING CAST 13 ECMU0076 WRIST PIN 14 ECMUSR04 SNAP RING FRANCO PISTON ...

Page 20: ...ISION BEARING 5 ECMOBE05 CRANK SEAL 6 ECMU0016 CRANK BEARING 7 ECMOBE07 CRANKSHAFT COMPLETE 8 ECMOBE08 FLYWHEEL KEY 9 ECMU0077 WRIST PIN BEARING 10 HCBC0660 6X60 CAP SCREW 11 HCBC0607 6X50 CAP SCREW 12 ZCMOBE12 CRANKCASE GASKET 13 ECMOBE13 OUTPUT SEAL 14 ECMOBE14 ROD WITH WRIST PIN AND BEARING 15 S6 V EC COM SET OF SEAL 16 ZKMOBE16 GASKET KIT 17 ECMOBE17 DOWEL PIN CASE 18 ECMOBE18 CASE VENT PIPE ...

Page 21: ...nally Cobra trues every crank before it leaves the factory and also welds the pin to keep it true If there are any problems send the engine in or call tech support 330 549 9603 to determine what the problem is CAUTION If you split the cases check the gear tooth faces for chapping signs of fatigue Check the small needle bearings for fatigue If the bearings are damaged the engine cases should be che...

Page 22: ...IP THRUST WASHER 8 HCBC0625 6X25 CAP SCREW 9 ECMPKS09 KICK START LEVER 11 HCBC0603 6X30 CAP SCREW 12 ZCMOKS12 CLUTCH COVER GASKET 13 ECMOKS13 THRUST WASHER 14 ECMOKS14 SEAL KICK START SHAFT 15 ECMOKS15 KICK START SHAFT WITH GEAR 16 ECMOKS16 KICK START SPRING 17 ECMOKS17 WASHER RETURN SPRING RETAINER 18 ECMOKS18 RETAINER CLIP RETURN SPRING 19 ECMOKS19 J SPRING KICK START 20 ECMOKS20 DOG GEAR 21 ECM...

Page 23: ...OCL09 WASHER CLUTCH BASKET BACK UP 10 PCMOCL10 SPROCKET 10 TOOTH 11 ECMOCL11 SNAP RING OUTPUT SHAFT 12 ECMOCL12 CLUTCH BASKET WITH GEAR 13 ECMOCL13 S6 TCBEI M5X14 SCREW FOR MASS 14 ECMOCL14 ADJUSTING SPRING 15 ECMOCL15 S6 D 2 5 BALL 16 ECMOCL16 S6 SPECIAL SCREW 17 ECMOCL17 FEDER ATAZZA 6 2X12X0 6 DIN 2093 18 ECMOCL18 CLUTH WASHER 19 ECMOCL19 CLUTCH SHOE 21 ECMOCL21 S6 CLUTCH PAWL 22 ECMOCL22 CLUTC...

Page 24: ...0 CAP SCREW 5 ECMOIG05 COIL WITHOUT SPARK PLUG CAP 6 ECMOIG06 CDI BOX 7 ECMOIG07 SPARK PLUG 8 ECMOIG08 SPARK PLUG CAP 9 ECMOIG09 RUBBER FOR CONTROL UNIT 11 HCBC0502 5X20 CAP SCREW 12 HCBC0550 5X50 CAP SCREW 13 ECMOIG13 7MM DOWEL 14 ECMOIG14 IGNITION COVER GROMMET OPEN 15 ECMOIG15 IGNITION COVER GROMMET CLOSED 16 ECMOIG16 SPACER FLYWHEEL 18 ECMOIG18 IGNITION COVER 20 ECMOIG20 FLYWHEEL GROMMET 21 HC...

Page 25: ...P 4 ECMOWP04 SPACER WATER PUMP BEARING 5 ECMOWP05 CRANK PULLEY 6 ECMOWP06 WATER PUMP BELT 7 ECMPWP07 CLAMP FOR OIL TUBE 8 HCBC0501 5X12 CAP SCREW 9 ECMPWP09 OIL INJECTOR MOUNT PLATE 10 ECMPWP10 OIL PUMP WITH TUBE 11 ECMOWP11 WATER PUMP IMPELLER 12 ECMOWP12 SNAP RING TOOTHED 13 ECMOWP13 WATER PUMP SEAL 14 ECMOWP14 WASHER BEARING RETAINER 15 ECMPWP15 DOWEL PIN 16 HCWF0501 5MM WASHER ...

Page 26: ...O DESCRIPTION 1 ECMPIN01 12MM CARBURETOR 2 ECMOIN02 CLAMP 3 HCBC0625 6X25 CAP SCREW 4 ECMOIN04 REED SPACER PLATE 5 ZCMOIN05 REED VALVE GASKET 6 ECMOIN06 REED VALVE ASSEMBLY 8 ECMOIN08 SCREW REED CAGE TO SPACER PLATE 9 ECMOIN09 RUBBER INTAKE BOOT 10 ECMOIN10 INTAKE RETAINING PLATE ...

Page 27: ...e it This means cracks chips and ruptures Anything abnormal replace the reeds Take the reed cage out and hold it up to the light and look in through the cage If you see light between the reed pedals and the frame then replace the reeds If you do not see light then the reeds should be ok See figure 25 Figure 16 The presence of light indicates that the reeds should be replaced or possibly turned ove...

Page 28: ...006 7 TOP CARB SCREW RCOI 0007 8 ORING FOR CARB TOP RCOI 0008 9 CARB TOP W ORING RCOI 0009 10 SLIDE SPRING RCOI 0010 11 NEEDLE RETAINER PLATE RCOI 0011 12 NEEDLE CLIP RCOI 0012 13 IDLE ADJUSTMENT SCREW RCOI 0013 14 IDLE ADJUSTMENT SPRING RCOI 0014 16 FUEL MIXTURE SCREW KIT 4 PIECE RCOI 0016 17 FLOAT KIT 3 PIECES RCOI 0017 19 FLOAT BOWL WITH ORING 2 PC RCOI 0019 20 BOTTOM CARB SCREW RCOI 0020 22 CH...

Page 29: ... filter can cause the engine to run rich NOTE Also before changing jetting insure that your carburetor has a proper float height of 5 If the engine is running rich on the top end it should be leaned out Leaning it out can be done by 1 Changing the main jet to a smaller number 2 Raising the needle clip this lowers the jet needle one notch at a time on the slide Indications that the engine is runnin...

Page 30: ...ake sure the fuel is shut off 2 Remove the carburetor 3 Drain the fuel in the carburetor 4 Disassemble the carburetor CAUTION Do not use compressed air on an assembled carburetor Or the pressure may deform the float Do not use a strong carburetor cleaning solution which could attack the parts of the carburetor instead use a mild high cleaning solution safe for plastic parts 5 Immerse all the metal...

Page 31: ...alls of the inside of the pipe Over a long period of time the diameter of the pipe will decrease due to carbon build up So it is essential to clear the residue CAUTION It is important to repack the silencer Signs of your silencer needing to be repacked are The bike is louder than normal A loss of power Chassis Service Parts CS1 Wheels Tires Rear wheel pullers Disassembly Figure 19 1 Remove axle an...

Page 32: ...asure from the side of the swing arm to the outer edge of the rim and make sure both sides are equal 2 Adjust the wheel pull bolt on the rear wheel puller to get the distance from the swing arm to the rim about the same ...

Page 33: ... SCMU0004 CAP 4 SCMU0300 BODY 5 HCNJ1001 LOCKNUT 6 SCMU0311 BUSHING 7 ZCMU0023 ENERGIZER 8 SCMU0305 PISTON 9 SCMU0322 STOP DISK 10 SCMU0301 SHAFT 11 SCMU0320 PISTON BUMPER 12 SCMU0312 BUFFER DISK 13 SCMU0310 BUFFER SEAL 14 ZCMU0114 LOADER 15 SCMU0314 BUSHING RETAINER 16 SCMU0306 BUSHING 17 ZCMU0216 O RING 18 SCMU0308 SEAL HEAD 19 SCMU0309 ROD WIPER 20 SCMU0316 BUMPER 21 SCMU0317 BUMPER SPACER 22 H...

Page 34: ...ycling 5 Clean the components of old oil and contaminates 6 Look for signs of wear and replace if necessary Assembly 1 If the bleed valve was removed clean the threads of both components apply some Teflon pipe sealant to the threads of the bleed valve and install torque to 10 ft lb 14 Nm 2 With the bottom shock portion situated vertically fill with 2 5 wt often called 3 wt shock oil until 37 38 mm...

Page 35: ... 22 Because of different rider weights sizes and riding styles we offer various suspension options See Optional Components section of this manual for details on these and other optional components for your Cobra Motorcycle ...

Page 36: ...012 FORK SPRING 13 KCMZ0013 SWIPER 14 KCMZ0014 SNAP RING 15 KCMZ0015 FORK SEAL 16 KCMZ0016 WASHER 17 KCMZ0017 SNAP RING FOR PISTON 18 KCMZ0018 PISTON ROD REBOUND 18A KCMZ0018A PISTON ROD COMPRESSION 19 KCMZ0019 REBOUND SPRING 20 KCMZ0020 FORK LEG OUTER LEFT 21 KCMZ0021 FORK LEG 5 PIECE UNIT LEFT 22 HCWC0000 WASHER 23 HCBC0806 8 X 30 CS 25 KCMZ0025 TRIPLE CLAMP BOTTOM W STEM 26 KCMZ0026 FORK TUBE I...

Page 37: ... in it e Compression is low i Piston ii Rings f Reeds are damaged g Ignition timing is incorrect 3 Engine is excessively loud a Silencer needs repacking 4 Engine blubbers at high RPMs a Jetting too rich 5 Engine won t start a Fuel i None in tank ii Is sour or bad b Carburetor is dirty c Ignition i Spark plug fouled ii Spark plug cap off iii Engine Shut off kill switch is shorted iv Bad electrical ...

Page 38: ... 23 Jetting How To 28 Stock 4 Kick Lever 21 Lubrication Recommended 4 Maintenance Schedule 10 Tips 10 Oil Recommended 4 Optional Components 6 Parts Bottom end 19 Clutch 22 Ignition 23 Inlet 25 Kick mechanism 21 Rear shock 32 Reeds 25 Top end 18 Water pump 24 Parts List Front Forks 34 Rear Shock 32 Petcock 8 Pullers 30 Rear Brake Adjustment 14 Rear Shock Service 33 Rear Wheel Pullers 30 Reeds 25 26...