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2007 King 50 

Owners 

Parts 

Service 

Tuning 

 

Summary of Contents for 2007 King 50

Page 1: ...2007 King 50 Owners Parts Service Tuning...

Page 2: ...osest Cobra dealer log on to www cobramotorcycle com or call 517 437 9100 If you need technical assistance contact your local dealer or call the Cobra Technical Support Hotline at 517 437 9100 Cobra M...

Page 3: ...OR 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 PRO...

Page 4: ...NTENANCE 14 AIR FILTER CLEANING 16 FORK OIL REPLACEMENT 19 FRICTIONAL DRIVE CFD 20 PARTS 21 PARTS AIRBOX INLET SYSTEM 21 PARTS BARS AND CONTROLS 22 PARTS CARBURETOR 23 PARTS COOLANT SYSTEM 24 PARTS EL...

Page 5: ...SERVICE 42 Base Gasket Selection 43 Engine Removal 45 Complete Engine Disassembly Procedure 46 Top End Disassembly Procedure 46 Splitting the Cases 47 Engine assembly 48 CLUTCH 50 IGNITION 55 COOLING...

Page 6: ...og advance Spark plug Champion 8339 1 8332 1 hotter 8904 1 colder Gap 0 023 0 025 0 58 0 64 mm Ignition timing 0 040 1 02 mm Before Top Dead Center BTDC Fuel type High octane pump gasoline RACE FUELS...

Page 7: ...h washers see clutch service section Pre filter for the airbox Sprockets o Front o Rear Suspension Springs Weight of Rider lb Fork Spring Shock Spring Less than 51 0 23 kg mm KCKG1223 gray 3 5 kg mm S...

Page 8: ...x 1 25 Engine mount bolts 22 265 30 M8 X 1 25 Swingarm Pivot 21 250 28 M14 X 2 0 Intake manifold bolts 4 6 55 6 2 M6 X 1 0 Rear Axle Bolt 25 300 34 M12 X 1 25 Rear Sprocket Bolts 18 216 24 7 mm Fork...

Page 9: ...e 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...

Page 10: ...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 knob to the vertically downward position reserve position is...

Page 11: ...and load requirements unique to the high engine speeds and centrifugal clutch of the Cobra 50cc motorcycles b Cobra Two Cycle Oil exceeds the JASO FD ISO L EGD specifications which are the worlds mos...

Page 12: ...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 Check the rims for signs of stress like cracks around...

Page 13: ...is engaging properly DO NOT feel the need to take the clutch apart to measure the spring stack clean the stack replace the springs etc Cobra has worked real hard to make a clutch that is low maintenan...

Page 14: ...side so that the clutch cover is up unless you have a squeeze bottle 6 Reapply the oil fill plug hand tight being sure the gasket is in place CAUTION Cobra has spent considerable time and money develo...

Page 15: ...rely and possible engine component failures Too much free play will not allow the rider to apply the brakes quickly 1 Set pedal height position first then 2 Set pedal free play Brake pedal height can...

Page 16: ...gure 2b 1 Loosen the lock nut 10mm 2 Undo the free play locking clip from around the brake adjustor plunger with your hand by pushing it forward 3 Slide the pin of the locking free play locking clip f...

Page 17: ...s from the airbox between the filter location and the carburetor NOTE Cobra has available a carburetor cover that allows easy cleaning of the airbox 1 Remove the air boot 2 Install the cover RCMU0109...

Page 18: ...gure A2 Figure A2 5 Squeeze the two finger tabs together on the wire retainer and install into the airbox while aligning the bottom guiding tabs legs with the arrows on the filter figures A3 A4 Figure...

Page 19: ...operly installed the filter and retainer should look like figure A7 with the filter material extending beyond the perimeter of the wire retainer Figure A7 NOTE Make sure you change or clean your filte...

Page 20: ...d Place upside down over a suitable pan tray or container e Work the damper rod up and down several times f Allow it to drain completely Assembly procedure 1 Fill the fork leg with 4 4 oz 130 ml 5 wt...

Page 21: ...ximum 125 169 With the clutch cover off you can check the slip torque by blocking the primary gear with a suitably strong device or Cobra tool EAMU0004 and then rotate the blue CFD nut counter clock w...

Page 22: ...MUDFLAP 7 HCBB0612 M6X12 BUTTON HEAD BOLT 8 MCKGHO03 HOSE CLAMP AIRBOX TO BOOT 9 RCKG0505 AIR BOOT 10 MCKGHO01 HOSE CLAMP BOOT TO CARB 11 MCKGHO04 HOSE CLAMP CARB TO MANIFOLD 12 ECKG0203 INLET MANIFOL...

Page 23: ...E LEVER W BALL 6 BCKG0024 BRAKE PERCH ASSY W LEVER BALL NOT SHOWN BAKG0004 SHIELDED BRAKE HOSE ASSEMBLY 7 FCMU0019 THROTTLE CABLE 8 HCBC0806 SOCKET HEAD CAP SCREW M8 X 30 4 PER 9S TKMU0404M BAR MOUNT...

Page 24: ...U0028 NEEDLE RETAINER PLATE 16 RCMU0007 NEEDLE CLIP 17 RCMU0204 CHOKE ASS Y 2001 CM 20 RCMU0009 FUEL MIXTURE SCREW 21 RCMU0011 IDLE ADJUSTMENT SCREW 25 RCMU0103 FLOAT BOWL GASKET 26 RCMU0107 FLOAT NEE...

Page 25: ...FT 4 MCKGHO02 RADIATOR HOSE BOTTOM RIGHT 5 MCMUGR03 MOUNTING GROMMET 3 PER 6 FCMU0006 RADIATOR MOUNTING BRACKET TEARDROP 7 HCBF0616 FLANGE HEAD BOLT M6X16 8 MCMUCL07 HOSE CLAMP 4 REQ D 9 FCKG0214 RADI...

Page 26: ...MBLY 4 HCBC0516 SCREW M5 X 16 2 PER 5 HCCN0000 5MM CLIP NUT 2 PER 6 ICMU0018 STATOR WITH GROMMET 7 HCBC0535 5mm x 35 SOCKET HEAD CAP SCREW 2 REQ D 8 HCBC0525 5mm x 25 SOCKET HEAD CAP SCREW 9 HCWF0504...

Page 27: ...TPUT SHAFT TRANSMISSION WITH GEAR 12 ECMU0100 SECONDARY SHAFT TRANSMISSION WITH GEAR 13 ECMU0001 BEARING TRANMISSION SECONDARY SHAFT 14 ECKG0031 BEARING OUTPUT SHAFT RIGHT SIDE 15 HCBH0612 M6X12 HEX H...

Page 28: ...2 ECMU0142 PLATE CFD 2 REQ D 13 ECMU0143 PAPER CFD 2 REQ D 14 ECMU0144 GEAR CFD 15 ECMU0145 SPRING WASHER CFD 16 HCWF0002 WASHER FLAT CFD 13MM 17 HCNS1202 NUT CFD 20 LEFT HAND THREAD BLUE 18 EAMU0001...

Page 29: ...PUMP SHAFT 5 ECKG0073 IMPELLER WATER PUMP 6 ECKG0004 RETAINER WATER PUMP ASSEMBLY 7 HCBB0003 5MM X 12 BUTTON HEAD STAINLESS 8 HCWF0501 FLAT WASHER 9 ECKG0175 WATER PUMP PULLEY FAN TYPE DRIVEN 10 ECMU...

Page 30: ...G0012 WRIST PIN 8 ECMU0077 BEARING WRIST PIN 9 ZCMUOR07 O RING EXHAUST FLANGE 10 ECMU0086 EXHAUST FLANGE NOT SHOWN ZCMOTE11 O RINGS PIPE TO FLANGE 2 REQ D 11 HCBC0612 M6X12 EXHAUST FLANGE SCREW 2 REQ...

Page 31: ...M6X35 FLANGE HEAD BOLT NOT SHOWN HCHA0003 6MM CLIP NUT FOR FRONT PIPE MOUNT 9 XCMU0032 SILENCER NOT SHOWN XCMU0026 SILENCER PACKING KIT NOT SHOWN HCBB0408 M4 X 8 SILENCER SCREW 10 XCKG0009 PIPE SILENC...

Page 32: ...CBC0625 SOCKET HEAD CS M6X25 4 REQ D 11 HCBC0806 CAP SCREW M8X30 4 REQ D 12S TCMU0404 BAR MOUNT KIT SHORT 2 REQ D 12T TCMU0403 BAR MOUNT KIT TALL 2 REQ D 14 HCBC1001 M10X45 SOCKET HEAD CAP SCREW 2 REQ...

Page 33: ...3 KAKG0027 MID VALVE ASSEMBLY STANDARD KAKG0026 MID VALVE ASSEMBLY LIGHT KAKG0032 MID VALVE ASSEMBLY HEAVY 14 KCKG0022 CARTRIDGE CAP 15 KCKG0054 DAMPER TUBE CARTRIDGE 5 star 16 KAKG0024 BASE VALVE ASS...

Page 34: ...9 MCMUGR03 GROMMET 2 REQ D PER BOLT 10 TCKG0001 ALUMINUM SPACER 11 HCWF1478 PIPE GROMMET WASHER 12 HCBH0880 FRONT ENGINE MOUNT BOLT M8X30 SHCS 13 HCNL0801 8MM LOCKNUT 14 HCBH1403 SWINGARM PIVOT BOLT...

Page 35: ...PIVOT BOLT 10 BCBH0602 M6 X 20 HEX HEAD BOLT 11 HCNS0601 6MM NUT 12 TCMU0010 WIDE FOOTPEGS PAIR 13 TCMU0106 FOOTPEG SPRING SINGLE PIECE 14 HCBH0840 M8 X 40MM FOOTPEG BOLT 15 HCWF0801 8MM FLAT WASHER...

Page 36: ...10 HCBF0635 M6 X 35 FLANGE HEAD BOLT updated these for new fork bottoms 11 HCBF0616 M6 X 16 FLANGE HEAD BOLT 12 WCMUZT04 CABLE TIES 2 REQ D TO SECURE BRAKE LINE TO FORK GUARD 13 BCKG0031 BLEED KIT MU...

Page 37: ...3 WCKG1201 12 FRONT TUBE 4 WCKG0011 FRONT AXLE 5 WCMU0123 FRONT WHEEL SPACER X LARGE 6 WCMU0120 WHEEL BEARING 2 REQD 7 WCMU0032 WHEEL BEARING SPACER 8 WCMU0101 FRONT WHEEL SPACER LARGE 10 HCWF1202 FRO...

Page 38: ...NT BOLT 1 PER SIDE NOT SHOWN HCWP0002 SHROUD WASHER 1 PER SIDE 5 TCMU0113 SIDE NUMBER PLATE SET NOT SHOWN HCBB0516 M5X16 NUMBER PLATE MTG SCREW 2 PER SIDE NOT SHOWN HCWP0002 NUMBER PLATE WASHER UPPER...

Page 39: ...BCKG0010 REPLACEMENT BRAKE HOSE 12 HCBF0635 M6X35 FLANGE HEAD BOLT 13 HCBF0620 M6X20 FLANGE HEAD BOLT 14 BCKG0013 CALIPER REAR BRAKE ACCESSORY BKKG0001 BRAKE PADS WITH E CLIP 15 BCKG0103 BRAKE CARRIER...

Page 40: ...OCKET NO DAMPERS 7 WCMU0020 WHEEL BEARING BRAKE SIDE 9 HCBH0702 M7X30 HEX HEAD BOLT 10 PCMU0100 CHAIN 420 X 100 11 PCMU0001 MASTER LINK 420 12 WCMU0016 REAR AXLE 13 HCPA0002 AXLE HEAD FIXING PLATE 14...

Page 41: ...CK RING 4 SCKGFX37 SHOCK SPRING 3 7 KG MM STANDARD SCKGFX35 SHOCK SPRING 3 5 KG MM LIGHT SCKGFX39 SHOCK SPRING 3 9 KG MM HEAVY 5 SCKGFX03 SPRING RETAINER BOTTOM 6 SCKGFX01 COLLAR SHOCK END MOUNT 7 ZCM...

Page 42: ...401 1 4 LOCKNUT 2 PER 12 HCBF0620 M6 X 20 FLANGE HEAD BOLT 2 PER 13 HCCC0000 BRAKE HOSE CLAMP 2 PER 14 HCPP0832 BRAKE HOSE CLAMP FASTNER 2 PER 15 HCBF1040 M10 X 40 LOWER SHOCK MOUNT BOLT 16 FCMU0203 W...

Page 43: ...before you establish the most accurate reading possible Because of the geometry of the spark plug used in this Cobra Motorcycle the adapter used with your compression tester must have a similar volume...

Page 44: ...at TDC and there are negative effects of either having too much or too little clearance Since parts like the crank connecting rod cylinder head piston and crankcases all have varying tolerances Cobra...

Page 45: ...nough such that the tip of the wire touches the cylinder wall against one side or the other not the front or back as the piston will rock and give incorrect measurement Hold the wire at this position...

Page 46: ...22 mm wrench 8 10 14 17 19 mm sockets 3 4 5 mm hex key Allen wrench 7 mm nut driver flat or Phillip screwdriver for hose clamps Spring remover Flywheel clutch puller MCMUTL68 Clutch nut removal tool...

Page 47: ...rom the water pump shaft 4mm and slide off the belt cover and the water pump belt 3 Using a flywheel holding tool and 14 mm socket remove the nut that secures the flywheel 4 Using the Cobra flywheel c...

Page 48: ...deposits and missing coating 1 If abrasions scrapes scratches pitting etc are found replace the cylinder 2 If deposits are all are found a Clean with muratic acid b Once the deposits are removed insp...

Page 49: ...uple months of hard racing Engine assembly CAUTION For any seals that are to be installed apply a light amount of grease to the seals ID assembly lube on all bearings and a small amount of Loctite to...

Page 50: ...ngine and put assembly lube on the connecting rod bearing 12 Install the piston rings CAUTION Ring end gap should be no less than 0 25 mm 0 010 and no more than 0 64mm 0 025 13 Install the base gasket...

Page 51: ...D 25 Install the clutch per Clutch Installation section in this manual 26 Install the coolant drain plug with copper washer 11 ft lb 15 Nm 27 Make sure that the exhaust spacer is on the cylinder 53 in...

Page 52: ...ve the center shoulder bolt out of each clutch shoe You will probably have to heat the center hub again to remove the bolts Once you get a bolt loosened carefully remove it with the shoe and observe t...

Page 53: ...reasing the flat washer s thickness increases the engine speed for clutch engagement thus increasing the abruptness of clutch engagement harder hit Conversely decreasing the flat washer s thickness de...

Page 54: ...rider is blipping the throttle This makes the clutch and clutch springs wear out quicker This also makes your engine tend to run hotter which decreases engine power and degrades ignition stator effici...

Page 55: ...oving all old thread locking material 3 Apply high strength thread lock material to the stack bolt and tighten to 12 ft lb 16 N m CAUTION Avoid allowing excess thread lock material to contact the spri...

Page 56: ...8 ft lb 7 8 Nm INSPECTION NOTE a There must be in out play in installed clutch 0 4mm to 1 0 mm 0 015 to 0 040 b Excess in out will cause early crank seal failure c A blue clutch drum is worn out from...

Page 57: ...ter that means 0 040 before the piston reaches the highest point of it s travel in the cylinder CAUTION Advancing the ignition timing will cause the engine to run hotter in turn causing power loss sho...

Page 58: ...g back in and firmly stick the spark plug cap onto the spark plug Cooling System The water pump in the engine keeps the radiator fluid in circulation throughout the motor The air stream running throug...

Page 59: ...ropane torch in step 12 2 Remove radiator cap and drain engine coolant by removing the 13mm hex head coolant drain plug 3 If the impeller is damaged or broken completely back flush the coolant system...

Page 60: ...ove impeller seal and both bearings Check shaft for wear in the area of the seal If there is any sign of wear like a groove replace the shaft Figure 40 12 Reinstall new bearings seal open side toward...

Page 61: ...silicon or Teflon pipe sealant to the tapered pipe threads of the coolant fitting before assembly NOTE Refill the coolant system with Liquid Performance Propylene Glycol based Mini Coolant Antifreeze...

Page 62: ...DLE ADJUSTMENT SCREW 25 RCMU0103 FLOAT BOWL GASKET 26 RCMU0107 FLOAT NEEDLE 27 RCMU0012 DIFFUSER 28 RCMU0016 FLOAT RETAINER PIN 29 RCMU0106 FLOAT BOWL 30 31 RCMU0201 BOTTOM FLOAT SCREW 33 RCMU0269 VEL...

Page 63: ...htly rich as opposed to slightly lean This is because an overly rich engine will just run poorly while an overly lean engine will seize potentially causing an expensive top end rebuild and a DNF To ri...

Page 64: ...the carburetor 4 Disassemble the carburetor 5 Immerse all the metal parts in a carburetor cleaning solution 6 After the parts are cleaned dry them with compressed air 7 Blow out the fuel passages with...

Page 65: ...gure 44 The presence of light indicates that the reeds should be replaced or possibly turned over Exhaust The pipe is a crucial element to a motorcycle Any kinks dents or damage done to the pipe will...

Page 66: ...fore each ride Make sure the brake does not have any leaks by holding the lever in while checking hose connections Make sure the brake lever pressure is OK by pulling in on the lever and ensuring full...

Page 67: ...bottom of the fork leg 22mm wrench 5 Pry the dust seal swiper from its position with a small screw driver 6 Using a pick remove the wire retaining ring holding the fork seals into place 7 Pop the for...

Page 68: ...seal swiper into the groove in the upper tube 11 Reinstall the damper cartridge assembly to the fork leg Secure the large bolt with 22 mm wrench to 35 ft lb with green thread locking agent 12 Fill wit...

Page 69: ...ck is fully serviceable but it is recommended that only trained professionals should service your shock Contact Cobra or PR2 for questions and service of your CX50 sr shock Shock preload Figure 47 Sho...

Page 70: ...mproper gearing Poor performance Not enough top end speed No snap Over heat clutch Premature failure of engine seals bearings electronics High clutch wear Condition Gear Taller Gear Lower Mud Sand Hil...

Page 71: ...43 15 37 2 47 14 35 2 50 15 38 2 53 13 33 2 54 14 36 2 57 15 39 2 60 13 34 2 62 14 37 2 64 15 40 2 67 13 35 2 69 14 stock 38 2 71 15 41 2 73 13 36 2 77 14 39 2 79 15 42 2 80 13 37 2 85 14 40 2 86 13 3...

Page 72: ...pring 2 2 1 Stiffer spring stiffer throughout the travel 2 2 2 Less stiff spring less stiff throughout the travel 2 3 Compression damping 2 3 1 Harder more damping slower adds resistance to the suspen...

Page 73: ...active Suspension Adjustments Once you have the suspension adjusted for decent overall feel you can make proactive adjustments when faced with different racing conditions Situation Actions Sand track...

Page 74: ...ents Condition Mixture will be Required adjustment Cold air Leaner Richer Warm air Richer Leaner Dry air Leaner Richer Very humid air Richer Leaner Low altitude Standard None High altitude Richer Lean...

Page 75: ...ustment To raise the idle turn the screw in clockwise in 1 4 turn increments and rev the engine after each adjustment To lower the idle turn the screw counter clockwise TOP END JETTING Adjust for clea...

Page 76: ...se gasket 2 Engine is down on power a Clutch engagement is not set properly b Jetting is incorrect c Silencer needs repacked d Exhaust pipe i Has excess carbon buildup ii Has large dent in it e Compre...

Page 77: ...e a Idle knob needs adjusted b Carburetor jets are dirty Index Air Filter 16 Bars and Controls 22 Base Gasket Selection 43 Break In 8 Carburetor Parts 23 Service 61 Specifications 5 CFD Cobra Friction...

Page 78: ...Frame 33 Front Brake 35 Front Wheel 36 Ignition Water Pump 28 Plastic Seat 37 Rear Brake 38 Rear Wheel 39 Shock 40 Swingarm 41 Top End 29 Triple Clamps 31 Plastic Seat Parts 37 Pullers 65 Rear Brake A...

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