Aeon COBRA 50 2007 Service Manual Download Page 48

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ENGINE / TRANSMISSION

Accessible Components

NOTE: The top-end of the engine can be serviced

without pulling the engine from the ATV. Loosen the

upper steering post mounting bolts to allow enough

clearance to remove cylinder head and cylinder.

However, it is recommended to pull the engine to

service top-end components.

The following components can be serviced or removed with the

engine installed in the frame:

• Flywheel

• Alternator/Stator

• Starter Motor/Starter Drive

• Oil pump

• Carburetor

• Transmission

The following components require engine removal for service

• Cylinder Head

• Cylinder

• Piston / Rings

• Crankshaft

• Crankshaft Main Bearings

• Crankcase

NOTE: Crankshaft components are not serviceable.

Replace crankshaft as an assembly.

4.4

Summary of Contents for COBRA 50 2007

Page 1: ...side of the vehicle are from the operator s perspective when seated in a normal riding position Some procedures outlined in this manual require a sound knowledge of mechanical theory tool use and shop procedures in order to perform the work safely and correctly Technicians should read the text and be familiar with service procedures before starting the work Certain procedures require the use of sp...

Page 2: ...he operator bystander or person s inspecting or servicing the vehicle SAFETY ALERT CAUTION indicates a potential hazard that may result in minor personal injury or damage to the vehicle CAUTION indicates special precautions that must be taken to avoid vehicle damage or property damage NOTE NOTE provides key information by clarifying instructions IMPORTANT IMPORTANT provides key reminders during di...

Page 3: ...1 GENERAL INFORMATION 1 MAINTENANCE 2 CVT 3 ENGINE TRANSMISSION 4 FUEL SYSTEM 5 BODY SUSPENSION STEERING 6 BRAKES 7 ELECTRICAL 8 2 3 4 ...

Page 4: ...APTER 1 GENERAL INFORMATION 1 INFORMATION 1 2 ENGINE SERIAL NUMBER LOCATION 1 2 VEHICLE IDENTIFICATION NUMBER LOCATION 1 2 GENERAL SPECIFICATIONS 1 3 MODEL 2007 NEW COBRA 50 1 3 VEHICLE COMPONENT INSPECTION LOCATIONS 1 4 1 1 ...

Page 5: ...out an engine be sure to refer to the engine serial number This information can be found stamped on the top LH side of the crankcase as shown below Vehicle Identification Number Location The vehicle identification number VIN and engine serial number are important for identification purposes See the illustrations 1 2 ...

Page 6: ... Kicker LUBRICATION OIL CAPACITY Oil Injection 1 Liter TRANSMISSION Automatic C V T system TIRE FRONT 19 7 8 REAR 18 9 5 8 OVERALL DIMENSION 1676 961 5 1007 mm GROUND CLEARANCE 112 mm SUSPENSION FRONT Duo shocks with single A arm REAR Swing arm with Single shock BRAKE FRONT Drum REAR Disc WHEELBASE 1051 mm SEAT HEIGHT 800 mm DRY WEIGHT 129 kg MAX LOAD 140 kg FUEL Unleaded Gasoline FUEL CAPABILITY ...

Page 7: ...GENERAL INFORMATION Vehicle Component Inspection Location ...

Page 8: ...TTLE STOP SPEED CONTROL SYSTEM 2 8 CHOKE CABLE ADJUSTMENT 2 8 IDLE SPEED ADJUSTMENT 2 8 FUEL LINES 2 8 PILOT AIR SCREW ADJUSTMENT 2 9 FUEL FILTER 2 9 FUEL VALVE LOCATION 2 10 CARBURETOR DRAINING 2 10 AIR FILTER SERVICE 2 11 ENGINE 2 12 ENGINE OIL LEVEL 2 12 ENGINE OIL AND FILTER CHANGE 2 12 ENGINE MOUNTS 2 13 ENGINE FASTENER TORQUE 2 13 CVT DRYING 2 13 TRANSMISSION AND FINAL DRIVE 2 14 TRANSMISSIO...

Page 9: ...E ADJUSTMENT 2 21 FRONT SUSPENSION INSPECTION 2 21 REAR SUSPENSION INSPECTION 2 22 SUSPENSION SPRING ADJUSTMENT 2 22 BRAKE SYSTEM 2 22 BRAKE SYSTEM INSPECTION 2 22 BRAKE LEVER TRAVEL 2 22 BRAKE FREEPLAY 2 23 FRONT BRAKE ADJUSTMENT 2 23 WHEELS AND TIRES 2 24 WHEELS 2 24 WHEEL HUB AND SPINDLE TORQUE TABLE 2 24 WHEEL INSPECTION 2 24 WHEEL REMOVAL FRONT REAR 2 24 WHEEL INSTALLATION FRONT REAR 2 24 TIR...

Page 10: ...d more frequently Severe Use Definition Frequent immersion in mud water or sand Racing or race style high RPM use Prolonged low speed heavy load operation Extended idle Short trip cold weather operation Pay special attention to the oil level A rise in oil level during cold weather can indicate contaminants collecting in oil sump or crankcase Change oil immediately if the oil level begins to rise M...

Page 11: ... Ride Inspect clean often replace as needed Air box sediment tube Daily Drain deposits when visible Head lamp tail lamp Daily Check operation apply dielectric grease if replacing CVT housing Weekly Drain water as needed check often if operating in wet conditions Brake lever travel 10H Monthly 150 Inspect regularly Brake freeplay 10H Monthly 150 Inspect regularly Spark plug 10H Monthly 150 Clean ch...

Page 12: ...ed Drive belt 50H 6M 800 Inspect replace as needed Fuel system 100H 12M 1500 Check for leaks at tank cap lines fuel valve filter carburetor replace lines every two years Fuel filter 100H 12M 1500 Replace yearly Engine mounts 100H 12M 1500 Inspect Exhaust muffler pipe 100H 12M 1500 Inspect Ignition timing 100H 12M 1500 Inspect Wring 100H 12M 1500 Inspect for wear routing security apply dielectric g...

Page 13: ...engine areas Always consult the exploded views in each manual section when available for torque values of fasteners before using standard torque Standard Fastener Torques Thread Size TORQUE ft lbs in lbs TORQUE Nm 5 mm bolts and nuts 39 52 in lbs 4 5 6 Nm 6 mm bolt and nuts 69 104 in lbs 8 12 Nm 8 mm boltsand nuts 13 18 ft lbs 18 25 Nm 10 mm bolts and nuts 22 29 ft lbs 30 40 Nm 12 mm bolts and nut...

Page 14: ...surface 2 Shift the transmission into neutral if equipped 3 Lock the parking brake 4 Push the engine stop switch up to the RUN position 5 Turn the key ON 6 Fold out the kick start lever and place your foot on the lever Thrust your heel downward to crank the engine 7 After the engine has started fold the kick start lever into place 2 6 MAINTENANCE FUEL SYSTEM AND AIR INTAKE Fuel System Safety ...

Page 15: ...e opens IMPORTANT This procedure should be performed by consumers only when they determine that their child is capable of handling the additional speed 1 Loosen the jam nut 2 Turn the screw inward to reduce speed or outward to increase speed 3 Tighten the jam nut after adjusting 2 7 MAINTENANCE ...

Page 16: ...ble for kinks or sharp bends in routing Idle Speed Adjustment 1 Start engine and warm it up thoroughly 2 Adjust idle speed by turning the slide adjustment screw in clockwise to increase or out counterclockwise to decrease RPM Refer to illustration Idle Speed 1500 100 Fuel Lines 1 Check fuel lines for signs of wear deterioration damage or leakage Replace if necessary 2 Be sure fuel lines are routed...

Page 17: ...lockwise until idle RPM begins to drop Stop turning at this point 4 Center the mixture screw between points in Step 2 and 3 5 Readjust idle speed if not within specification Fuel Filter The fuel filter should be replaced in accordance with the Periodic Maintenance Chart or whenever sediment is visible in the filter Fuel Filter Location Located in line between fuel valve and carburetor inlet To ser...

Page 18: ...extended periods of storage 1 Turn fuel valve to the OFF position 2 Place a container beneath the bowl drain hose 3 Loosen drain screw and allow fuel in the float bowl and fuel line to drain completely 4 Inspect the drained fuel for water or sediment 5 Tighten drain screw 6 Turn fuel valve to ON 7 Check for fuel leaks 8 Start engine and re check for leaks ...

Page 19: ...ter Wash the foam filter in warm soapy water then rinse and let it dry If the filter is damaged install a new foam filter 3 Apply a commercially available foam filter oil to the foam filter 4 Reinstall the screen foam filter and air box cover Secure the clips 5 The inlet pipe must toward rear of vehicle ...

Page 20: ...e Filling over the normal operating range could cause a mist of oil to enter the air box 5 Reinstall the filler plug Transmission Oil Change 1 Position the vehicle on a level surface 2 Clean area around the drain plug 3 Run engine two to three minutes until warm 4 Stop the engine 5 Place a drain pan beneath the mission case 6 Remove the drain plug Allow the oil to drain completely 7 Inspect the O ...

Page 21: ...y There may be some instances when water is accidently ingested into the CVT system Use the following instructions to dry it out before operating The drain plug is located on the bottom of the CVT cover 1 Remove the drain plug located under the CVT housing Allow the water to drain Reinstall the drain plug 2 Shift the transmission into neutral 3 Start the engine Apply varying throttle for 10 15 sec...

Page 22: ...de of the gear case on the right side of the ATV Maintain the lubricant level at the bottom of the fill plug hole threads uld be checked monthly and changed annually 1 Position the vehicle on a level surface 2 Remove the fill plug 3 View the lubricant level through the fill hole 4 If the level is low add the recommended lubricant 5 Reinstall the fill plug Transmission Lubricant Change 1 Position t...

Page 23: ...ain deflection 2 Collapse the suspension with an adjustable trailer tie down Fasten the strap around the axle and rear bumper tube 3 Tighten the strap while compressing the suspension to create a straight sight line between the rear axle and the gear case output shaft This establishes the tightest chain position 4 Pull down on the tensioner to move it out of the way then measure the chain deflecti...

Page 24: ...bolts 2 Loosen the chain adjuster lock nut 3 Turn the chain adjuster clockwise until chain tension is set to specification 2 15 MAINTENANCE 4 Tighten the chain adjuster lock nut to 84 in lbs 9 4 Nm and re verify the chain tension is at specification ...

Page 25: ...over Sprocket Inspection Inspect the front and rear sprockets for worn broken or bent teeth To check for wear pull upward on the chain at the top of the rear sprocket Replace sprocket if chain movement exceeds 1 4 0 6 cm 2 16 MAINTENANCE ELECTRICAL AND IGNITION SYSTEM Battery Removal ...

Page 26: ...n its holder 2 Attach the hold down strap s 3 Connect and tighten the red positive cable first 4 Connect and tighten the black negative cable last 5 Torque the battery terminal bolts to 3 5 ft lbs 4 7 Nm 6 Verify that the cables are properly routed NOTE When installing a new battery make sure it s fully charged prior to its initial use Using a new battery that has not been fully charged can damage...

Page 27: ...n with electrical contact cleaner or a glass bead spark plug cleaner only CAUTION A wire brush or coated abrasive should not be used 5 Measure gap with a wire gauge Refer to specifications for proper spark plug type and gap Adjust gap if necessary by bending the side electrode carefully 6 If necessary replace spark plug with proper type CAUTION Severe engine damage may occur if the incorrect spark...

Page 28: ...ed steering components Steering should move freely through entire range of travel without binding Check routing of all cables hoses and wiring to be sure the steering mechanism is not restricted or limited Due to the critical nature of the procedures outlined in this chapter Polaris recommends steering component repair and adjustment be performed by an authorized Aeon Dealer Only a qualified techn...

Page 29: ... freely through entire range of travel without binding Wheel Alignment Use the following procedure to check the toe alignment of the vehicle The recommended toe alignment is 1 8 to 1 4 3 6 mm toe out 1 Set the handlebars in a straight ahead position NOTE The steering arm can be used as an indicator of whether the handlebars are straight The arm should always point straight back from the steering p...

Page 30: ...o achieve the proper toe setting 1 8 to 1 4 Important When tightening the tie rod end jam nuts the rod ends must be held parallel to prevent rod end damage and premature wear Damage may not be immediately apparent if done incorrectly See illustration Front Suspension Inspection Compress and release front suspension Damping should be smooth throughout the range of travel Inspect the front shocks an...

Page 31: ...preload adjustments turn the adjuster cam to increase or decrease the amount of preload BRAKE SYSTEM Brake System Inspection The following checks are recommended to keep the brake system in good operating condition Service life of brake system components depends on operating conditions Inspect brakes in accordance with the maintenance schedule and before each ride Brake Lever Travel Check brake le...

Page 32: ... of the front and rear brakes at the intervals recommended in the Periodic Maintenance Chart If the freeplay isn t at specification adjust the freeplay as outlined below Brake Freeplay Specifications Front Brake Rear Brake 2 3mm 0 08 0 12 2 3mm 0 08 0 12 ...

Page 33: ...uster nut on the right hand control 5 When you begin to feel a slight drag on wheel rotation loosen the adjuster nut one full turn 6 While rotating the right front wheel tighten the lower front brake adjuster nut on the right hand control 7 When you begin to feel a slight drag on wheel rotation loosen the adjuster nut one full turn 8 Verify that the right hand brake functions correctly 9 Verify th...

Page 34: ... Wheel Removal Front Rear 1 Stop the engine place the transmission in gear and lock the parking brake 2 Loosen the wheel bolts slightly 3 Elevate the side of the vehicle by placing a suitable stand under the footrest frame 4 Remove the wheel bolts and remove the wheel Wheel Installation Front Rear 1 With the transmission in gear and the parking brake locked place the wheel in the correct position ...

Page 35: ...MAINTENANCE Tire Pressure Tire Pressure Inspection PSI Cold Front Rear 5 psi 5 psi Tire Inspection 2 25 ...

Page 36: ...N 3 2 DRIVEN CLUTCH OPERATION 3 2 CVT SYSTEM DRYING 3 3 CLUTCH COVER REMOVAL 3 4 DRIVE BELT REMOVAL 3 4 DRIVE CLUTCH SERVICE 3 5 DRIVE CLUTCH DISASSEMBLY AND INSPECTION 3 5 DRIVE CLUTCH ASSEMBLY 3 6 DRIVEN CLUTCH SERVICE 3 7 DRIVEN CLUTCH DISASSEMBLY AND INSPECTION 3 7 DRIVEN CLUTCH ASSEMBLY 3 8 3 1 ...

Page 37: ...s to push against the cam plate and force the moveable sheave toward the drive belt This motion pinches the drive belt between the spinning sheaves and causes it to rotate which in turn rotates the driven clutch If belt speed is sufficient centrifugal friction shoes on the driven clutch overcome their return spring pressure and swing outward against the transmission drive hub and the vehicle if in...

Page 38: ...ea remove the CVT drain plug and O ring located on the bottom of the crankcase and let the water drain out The CVT drain plug is shown at right 2 To further expel water from the CVT area cover and to dry out the CVT system shift the transmission to neutral and rev the engine slightly to expel the moisture This will also air dry the belt and clutches 1 Allow engine RPM to settle to idle speed shift...

Page 39: ...ch 2 Remove kick starter lever 2 Pull outer sheave of driven toward you and push belt as far as possible into driven sheaves to create belt slack 1 Remove all screw and cover with kick start spindle attached 3 Slide driven clutch off shaft with belt Remove belt from driven clutch sheaves and then from drive clutch 3 4 ...

Page 40: ...nd seals in the moveable sheave The sleeve should be a close smooth fit in the bushings and seals should fit tightly on the sleeve 3 Remove cam plate 4 Inspect surface of sleeve A for wear pitting or damage 7 Remove and inspect each roller Replace as a set if any have flat spots or if worn they should be cylindrical 5 Inspect cam plate for wear on surface B and splines C Replace cover guides D as ...

Page 41: ...n the middle and install the outer drive clutch sheave as far as possible Hold outer sheave in place 3 Install the cam plate 4 Install the bushing primary sliding sheave and cam plate assembly NOTE When installing the primary sliding sheave and the cam plate assembly hold the assembly together to prevent the rollers from dislodging 8 Install the claw washer engaging the inner spline of the washer ...

Page 42: ... page 3 4 4 Secure the driven clutch assembly in a soft jaw vise or clamp Loosen the retaining nut about 1 turn Hold downward pressure on the friction shoe plate and then remove the nut Release pressure on plate and remove the friction shoe assembly and driven spring 6 Remove rollers and pins using a needle nose pliers and inspect all components Replace if any damage or excess wear is found Replac...

Page 43: ...hub Measure the inside diameter of the hub using a caliper and compare to specification If either of these measurements exceeds the limit replace the drive hub Driven Compression Spring Length Service Limit 69 7mm 2 74 10 Inspect the surface of the drive belt for uneven wear or grease deposits Using a vernier caliper measure the width of the belt The service limit of the belt is 626 15 9 mm If the...

Page 44: ...lt over the drive clutch and install driven clutch on transmission shaft 5 Install driven clutch hub then the retaining nut and O ring Torque retaining nut to specification 2 Have an assistant available for final assembly Install the compression spring Place the friction pad assembly over the spring and compress the driven assembly together with both hands With the assembly compressed and the thre...

Page 45: ...DURE 4 9 HONING TO DEGLAZE 4 9 PISTON INSPECTION 4 10 PISTON RING INSTALLED GAP 4 11 BOTTOM END DISASSEMBLY 4 12 FLYWHEEL REMOVAL INSPECTION 4 12 STATOR REMOVAL 4 12 OIL PUMP REMOVAL 4 13 CRANKCASE DISASSEMBLY 4 15 CRANKSHAFT REMOVAL 4 15 CRANKSHAFT SPROCKET INSPECTION 4 15 TRANSMISSION 4 16 TRANSMISSION DISASSEMBLY AND INSPECTION 4 16 TRANSMISSION INSPECTION 4 17 TRANSMISSION ASSEMBLY 4 18 STARTE...

Page 46: ...ENGINE TRANSMISSION ENGINE SERVICE Engine Exploded Views Torque Values 4 2 ...

Page 47: ...ENGINE TRANSMISSION Engine Exploded Views Torque Values 4 3 ...

Page 48: ...ended to pull the engine to service top end components The following components can be serviced or removed with the engine installed in the frame Flywheel Alternator Stator Starter Motor Starter Drive Oil pump Carburetor Transmission The following components require engine removal for service Cylinder Head Cylinder Piston Rings Crankshaft Crankshaft Main Bearings Crankcase NOTE Crankshaft componen...

Page 49: ...om right side of frame Engine Installation Notes After the engine is installed in the frame review this checklist and perform all steps that apply General Items Install previously removed components using new gaskets seals and fasteners where applicable Perform checks on fluid levels controls and all important areas on the vehicle as outlined in the daily pre ride inspection checklist refer to Cha...

Page 50: ...oosen all four bolts of cylinder head cover 2 Remove cylinder head cover 3 Thoroughly clean cylinder head surface to remove all traces of gasket material and carbon 4 Remove the cylinder head gasket Stud bolt Use care not to damage sealing surface If there is damage found on the cylinder head combustion chamber it is recommended the component be replaced Cylinder head gasket 5 Tap cylinder lightly...

Page 51: ...osite from combustion chamber and valve seat area with a soft wire brush Inpection the combustion chamber for cracks and damage from foreign debris Low pressure compressed air can blow debris into your face and eyes Always wear eye protection or a face shield when using pressurized air Failure to take adequate safety precautions could result in death or serious injury CYLINDER WARP INSPECTION Repe...

Page 52: ...mm 002 Max Cylinder Out of Round Limit 05 mm 002 Max Cylinder Honing Procedure A hone which will straighten as well as remove material from the cylinder is very important Using a common spring loaded glaze breaker for honing is not advised Polaris recommends using a rigid hone or arbor honing machine Cylinders may be wet or dry honed depending upon the hone manufacturer s recommendations Wet honin...

Page 53: ...or damage is excessive replace cylinder Hone only enough to deglaze the cylinder bore Piston Inspection 1 Measure piston outside diameter at a point 3mm up from bottom of piston at a right angle to direction of piston pin 2 Carefully inspect the pistons for damage or excessive wear Discard piston with cracked broken or bent ring lands 3 Check the piston skirt for cracks gouges deep scratches or he...

Page 54: ...bbed thoroughly with hot soapy water rinsed and dried completely Wipe cylinder bore with an oil rag immediately to remove residue and prevent rust Piston Ring Installation NOTE Apply clean engine oil to all ring surfaces and ring lands Always check piston ring installed gap before rings are installed on piston If the piston has been in service clean any accumulated carbon from the ring grooves and...

Page 55: ...r or strike the tool or crankshaft may be damaged Stator Removal 1 Remove flywheel 2 Loosen stator screws A and pulse coil screws B evenly and remove stator Note wire routing for assembly B Stator Inspection Visual inspect the isolation of coil and pulse coil wires Measure resistance value of each stator leg the DC resistance value is 720 850 Negative Positive 4 11 A ...

Page 56: ...ws A and pulse coil screws B 3 Place the fly wheel then washer in crankshaft 4 fasten nut onto fly wheel Oil Pump Removal 1 Remove stator 1 Remove gasket 4 Take off the bolts then remove the oil pump 2 Clean up the grease on oil pump gear 5 Loosen the bolt then remove the circlip 4 12 Screw circlip ...

Page 57: ...ount bracket then circlip and dowel pin Oil tube inspection Inspect the tube leaking and broken Oil pump gear inspection Inspect the gear outside diameter by caliper Gear OD Limit 50 825mm min NOTE The CVT system starter motor starter drive flywheel stator oil pump and transmission can be serviced with the engine in the frame 4 13 Wave washer Mount bracket circlip Dowel pin ...

Page 58: ...ment and no detectable up and down movement 2 The connecting rod big end bearing is a roller bearing Visually inspect connecting rod big end for scoring damage or excessive wear If connecting rod passes visual inspection measure radial clearance carefully with crankshaft clamped in V blocks at points A and a dial indicator measuring total up and down movement B Compare to specifications If clearan...

Page 59: ...y pulling straight outward DO NOT LOSE the spring and plunger on the inner end of the shaft This plunger contacts the gear position switch 3 Mark shift selector shaft and shift lever arm so the arm can be reinstalled in the same location Remove arm and bracket 4 Remove cover with output shaft Push or tap on shift shaft to keep it in the case 8 Remove shift fork shaft 5 Remove gasket and discard 6 ...

Page 60: ...the 12mm hex bolt and remove the shift detent ball and spring assembly 11 Remove shift drum Push detent ball located at back against spring pressure to ease removal 12 If input shaft or gear requires service remove driven clutch as outlined in CVT Chapter 4 16 ...

Page 61: ...side to inside while supporting cover completely 5 Inspect sliding gear dogs and dog slots in the mating gears F for wear or damage The edges of dogs and slots should be square and not rounded Replace both sliding gear and mating gears if any edges are rounded or chipped NOTE Inspect all shafts for wear in the bearing contact areas The sealed output shaft bearing in the transmission cover has a sn...

Page 62: ...e sliding gear from the shaft 10 Remove the snap ring and thrust washer to access the reverse gear Shaft Assembly 11 Assemble the reverse gear washer a new snap ring and the sliding gear on the shaft 12 Replace gear and place it on the shaft followed by the washer G as shown 13 Grooves H on spacer face the washer Press spacer onto shaft until firmly seated against the step on the shaft 4 18 ...

Page 63: ...owing information and special notes 1 Use caution when installing the gear position indicator spring A and pin B located in the end of the shift shaft Removal of the indicator switch located under the clutch cover is recommended 2 Check transmission operation before final assembly and after installing outer cover and output shaft FORWARD NEUTRAL REVERSE 4 19 ...

Page 64: ... operation The ring gear should rotate smoothly and freely in a clockwise direction A The gear should lock and turn the crankshaft when rotated in a counterclockwise direction B 4 Remove idler gear from shaft 7 Hold the gear and the one way clutch together to prevent rollers from falling out of the clutch Remove the one way clutch and drive gear as an assembly 5 Remove thrust washer from shaft 8 L...

Page 65: ... springs plungers and rollers into the hub Push each roller back toward plunger and spring and then release Rollers should return freely to the extended position and stop against the hub 4 Place the starter gear 4 in the one way clutch 5 with a counterclockwise rotating motion Install the needle bearing 3 into the clutch then place inner ring 2 to clutch 5 Install idler gear washer on shaft and id...

Page 66: ... lever or kick drive components to remove the engine cover 1 Remove clutch cover and cover gasket Chapter 3 2 Remove the kick pinion with drag spring attached by rotating the kick start pedal 5 Remove retaining ring and backing washer from the shaft 3 Disconnect hooked end of spring and set against stop 6 Lift hooked end of spring over the stop and allow it to unwind completely about another 180 d...

Page 67: ...Torque 87 lb in 10 Nm 4 Install shaft with bushing and O ring into cover 5 Position hooked end C against stop and engage straight end D on edge of gear as shown 10 Install drag spring on kick gear with bend toward bevel gear 6 Hold spring up against kick gear and rotate gear counterclockwise until trailing edge E is past the stop F Push gear down until seated and then release gear to rest against ...

Page 68: ...ded battery terminals cables Starter motor electrical circuit faulty Engine seized or mechanical failure Kickstart components damaged Engine Runs But Will Not Idle Carburetor pilot idle circuit restricted or blocked Carburetor misadjusted Choke not adjusted properly Low compression Insufficient valve clearance too tight Crankcase breather restricted Air filter restriction Old degraded fuel Incorre...

Page 69: ...plug or plug gap Carburetion faulty lean condition Intake Exhaust system air leaks Spark plug cap cracked broken Ignition coil faulty Ignition or kill switch circuit faulty Ignition timing incorrect Sheared flywheel key Poor connections in ignition system wiring Ignition system wiring wet Cam lobe worn or valve sticking Lean condition Transmission Gear Will Not Engage Shift arm indexed incorrectly...

Page 70: ... THROTTLE 5 7 JET NEEDLE NEEDLE JET 3 8 3 4 THROTTLE 5 8 MAIN SYSTEM 3 4 TO FULL THROTTLE 5 8 FUEL DELIVERY 5 9 CARBURETOR SERVICE 5 9 CARBURETOR FLOAT BOWL DRAINING 5 9 CARBURETOR REMOVAL GENERAL 5 10 CARBURETOR DISASSEMBLY 5 10 CARBURETOR CLEANING 5 12 CARBURETOR INSPECTION 5 12 FLOAT HEIGHT ADJUSTMENT 5 13 CARBURETOR ASSEMBLY 5 13 NEEDLE AND SEAT LEAK TEST 5 13 FUEL OIL TANK EXPLODED VIEW 5 14 ...

Page 71: ...th soap and water and change clothing Carburetor Function Carburetor Component Function System Main Components Main Function Main Affect Float System Level Control Inlet Pipe Needle and Seat Float and Float Pin Maintains specified fuel level in float chamber carburetor float bowl All systems all throttle ranges Venting Passages in carburetor and vent lines Supplies atmospheric pressure to float ch...

Page 72: ...io under these varying conditions a low speed fuel system or pilot system and a main fuel system are provided in these type of carburetors The function of a carburetor is to produce a combustible air fuel mixture by breaking fuel into tiny particles in the form of vapor to mix the fuel with air in a proper ratio and to deliver the mixture to the engine A proper ratio means an ideal air fuel mixtur...

Page 73: ...el level should not be changed arbitrarily Pilot Jet From idling to low speeds the fuel supply is metered by the pilot jet There are several air bleed openings in the sides of the pilot jet which reduce the fuel to mist The number stamped on the jet is an indication of the amount of fuel in cc s which passes through the jet during a one minute interval under a given set of conditions Air Mixture S...

Page 74: ... be significantly affected A carburetor with a slide type throttle valve is also called a variable venturi type carburetor In this type of carburetor the needle jet and jet needle serve to control proper air fuel mixture ratio at the medium throttle valve opening between 1 4 and 3 4 opening Having the proper needle jet and jet needle has a major impact on engine performance at partial load The jet...

Page 75: ...he jet indicates the amount of fuel CCs which will pass through it in one minute under controlled conditions Larger numbers give a greater flow resulting in a richer mixture Throttle slide The throttle slide controls the rate of engine air intake by moving up and down inside the main bore At small throttle openings air flow control is performed chiefly by the cutaway By controlling air flow the ne...

Page 76: ...d When the air screw is opened the mixture is made more lean as the amount of air is Increased Slide Cutaway 1 8 3 8 Throttle Throttle valve cutaway effect is most noticeable at 1 4 throttle opening The amount of cutaway is pre determined for a given engine to maintain a 14 1 air fuel ratio at part throttle A steep angle would indicate a fairly lean mixture because there is less resistance to air ...

Page 77: ...m is made up of the jet needle needle jet and main jet The main system begins to take effect as soon as there is enough air flow into the carburetor venturi to draw fuel up through the main jet and needle jet assembly This system works in conjunction with the needle jet system During low speed driving there is very little clearance between the jet needle and the needle jet therefore very little fu...

Page 78: ...e jet have an effective operating range from approximately 1 8 to 7 8 throttle opening The amount of fuel delivered during this range relies upon the jet needle clip position as well as the needle jet size and other specifications The main jet affects fuel delivery at 1 4 throttle and consistently increases to full throttle opening CARBURETOR SERVICE Carburetor Float Bowl Draining The carburetor f...

Page 79: ...e carburetor and air cleaner 4 Loosen fuel tube clamp D then remove fuel tube 5 Loosen oil tube clamp then remove oil tube 6 Disconnect the choke cable end from the choke lever 7 Disconnect the throttle cable end from the throttle lever 8 Remove carburetor from ATV Carburetor Disassembly Use the following procedure to disassemble the carburetor 1 Remove the 4 float bowl screws and float bowl 2 Rem...

Page 80: ...rom the carb body 5 Note the position of both the air mixture screw and idle speed adjustment screw and remove both from the carb body 3 Loosen the choke seat screw Throttle Valve and Choke Disassembly 1 Loosen the cable nut and valve cover 4 Remove whole choke with cable then take apart as following ...

Page 81: ...ortion of the needle contacts the needle jet and is the most likely wear point If slide needle shows signs of wear replace both the needle and needle jet to prevent a rich condition 1 Thoroughly clean the carburetor body jets and all passages with carburetor cleaner or electrical contact cleaner 2 If the carburetor is extremely dirty or contaminated with fuel residue and varnish soak for short per...

Page 82: ...on with the float tongue resting lightly on the inlet needle valve pin without compressing the spring The bottom of the float should be parallel with the float bowl mating surface IMPORTANT When measuring the height verify the inlet needle valve spring is not compressed NOTE If the float is past parallel with the mating surface the carburetor has likely been tilted back too far and the float tongu...

Page 83: ...ntil it lightly contacts the seat Back out the specified number of turns NOTE The final air mixture screw must be adjusted with the engine running Air Screw Base Setting Set at Factory Factory Specification 50cc Mikuni 2 5 Turns Out Needle and Seat Leak Test 1 Install the float bowl 2 Invert the carburetor and install a Mity Vac PN 2870975 to the fuel inlet fitting 3 Apply 5 PSI pressure to inlet ...

Page 84: ...5 14 FUEL SYSTEM Fuel and oil tank location ...

Page 85: ...ank 1 Completely drain fuel from fuel tank Be sure the fuel valve is set to RES to get the majority of the fuel drained from the tank 2 Remove the two bolts that attach the fuel tank to the frame Oil Tank Removal 1 Completely drain oil from oil tank 2 Remove a bolt that attach the oil tank to the frame ...

Page 86: ...nd remove both fuel lines from the tank 5 To reinstall the tank reverse the removal procedure Be sure to torque the tank mounting bolts Fuel Oil Tank Mounting Bolt Torque 8 Nm 72 in lbs 3 Carefully lift up on the oil tank 4 Remove the oil line and oil gauge from the tank 5 16 FUEL SYSTEM ...

Page 87: ...AIR CLEANER EXPLODED VIEW 5 17 FUEL SYSTEM ...

Page 88: ... filter in warm soapy water then rinse and let it dry If the filter is damaged install a new foam filter 3 Apply a commercially available foam filter oil to the foam filter 4 Reinstall the screen foam filter and air box cover Secure the clips 5 The inlet pipe must toward rear of vehicle 5 18 FUEL SYSTEM ...

Page 89: ...ng or improperly routed Incorrect pilot air fuel screw adjustment Faulty inlet needle and seat Faulty inlet needle seat O Ring Float level too high Poor fuel quality old fuel Loose jets Worn jet needle needle jet or other carburetor parts Dirty carburetor air bleed passages or jets Weak or damaged choke plate return spring Fouled spark plug Poor Idle Idle Too High Idle adjusted improperly air mixt...

Page 90: ...NT BUMPER REMOVAL INSTALLATION 6 4 CAB EXPLODED VIEW 6 4 SUSPENSION 6 5 SHOCKS AND SPRINGS 6 5 FRONT SHOCK REMOVAL 6 5 REAR SHOCK REMOVAL 6 6 FRONT A ARM 6 7 A ARM EXPLODED VIEW 6 7 A ARM REPLACEMENT 6 7 SWING ARM 6 8 REMOVAL 6 8 STEERING 6 10 STEERING ASSEMBLY EXPLODED VIEW 6 10 STEERING POST REMOVAL 6 10 HANDLEBAR 6 11 EXPLODED VIEW 6 11 DECAL REPLACEMENT 6 11 6 1 ...

Page 91: ... 22 Nm 16 ft lbs Steering Post Nut 54 Nm 40 ft lbs Final Drive Fasteners Front Wheel Spindle Nut 59 Nm 44 ft lbs Rear Wheel Hub Nut 79 Nm 58 ft lbs Front Rear Wheel Bolts 30 Nm 22 ft lbs Sprocket Bolts Front 9 8 Nm 87 in lbs Rear 22 Nm 16 ft lbs Chain Tensioner Bolt 10 Nm 84 in lbs Bearing Carrier Mounting Bolts 54 Nm 40 ft lbs Chain Guard Bolts 22 Nm 16 ft lbs BODY REMOVAL 1 Lift up on the seat l...

Page 92: ...h side 9 Disconnect both front indicator plugs 7 Remove the 2 bolts attaching the body to the front cab on each side 10 Completely remove the front cab from body 11 Remove 2 footwells from body 12 Remove the 4 bolts of rear cab 8 Disconnect the headlight harness 13 Disconnect the taillight harness 14 Remove the 2 bolts attaching the rear cabs then take off taillight 6 3 ...

Page 93: ...Remove Rear cab from cab Front Bumper Removal Installation 1 Remove the 4 mounting bolts retaining the front bumper and remove the bumper from the ATV 2 Reverse the previous procedure to reinstall the bumper 3 Torque mounting bolts to 87 in lbs 9 8 Nm Front Bumper Mount Bolt Torque 10 Nm 90 in lbs Body Exploded View 6 4 ...

Page 94: ...ury could occur if machine tips or falls 2 Remove the upper shock mounting bolt from the frame and the lower shock mounting bolt from the front suspension arm A arm 3 Replace the shock or spring as required 4 Install shock as shown in Figure 5 8 5 Torque shock mounting bolts to specification Front Shock Mounting Bolt Torque 34 Nm 25 ft lbs 6 5 ...

Page 95: ...ld occur if machine tips or falls 2 Remove the upper shock mounting bolt from the frame and the lower shock mounting bolt from the swing arm 3 Replace the shock spring or adjuster cam as required 4 Install the shock as shown in Figure 5 9 5 Torque shock mounting bolts to specification Front Shock Mounting Bolt Torque 36 Nm 49 ft lbs 6 6 ...

Page 96: ...r enough to remove the wheel Severe injury could occur if machine tips or falls 2 Remove the dust cap and cotter pin 3 Remove wheel nut and remove wheel and hub as an assembly 4 Remove the cotter pin from the upper spindle castle nut and remove the nut 5 Slide the spindle assembly out from the end of the control arm 6 7 ...

Page 97: ...ccur if machine tips or falls 2 Remove the dust cap and cotter pin from 2 rear wheels 3 Remove 2 rear wheels nut and remove wheel and hub as an assembly 7 Remove A arm from the ATV 8 To reinstall reverse steps 1 7 Torque all fasteners to specification Inner Control Arm Bolt Torque 34 Nm 25 ft lbs Front Shock Mounting Bolt Torque 34 Nm 25 ft lbs Wheel Nut Torque 59 Nm 44 ft lbs 3 Remove the chain p...

Page 98: ...om caliper then remove caliper 6 Ensure don t loosen brake oil tube bolt 9 Remove 4 axle hub bolts from swing arm 10 Slide axle out of the axle housing and rear sprocket and remove the housing and sprocket assemblies 7 Loosen 2 nuts from rear axle 9 Remove a through bolt lower shock mouting bolt from swing arm and remove swing arm from body 6 9 ...

Page 99: ...lts Steering Post Removal 1 Remove handlebar fasteners and retainer block 3 Remove the inner tie rod nuts and the steering post nut 4 Carefully remove the steering post from the ATV 5 To reinstall reverse steps 1 4 Torque all fasteners to specification See torque specifications listed in the exploded view 6 10 ...

Page 100: ...ame treated prior to installing a decal to ensure good adhesion A bonus of the flame treating procedure is it can be used to reduce or eliminate the whitish stress marks that are sometimes left after a fender or cab is bent flexed or damaged To flame treat the decal area 1 Pass the flame of a propane torch back and forth quickly over the area where the decal is to be applied until the surface appe...

Page 101: ...ATIONS 7 2 GENERAL SPECIFICATIONS 7 2 TORQUE SPECIFICATIONS 7 2 FRONT BRAKES 7 3 EXPLODED VIEW 7 3 FRONT BRAKE SERVICE 7 3 REAR BRAKE 7 6 EXPLODED VIEW 7 6 REAR BRAKE SERVICE 7 6 REAR CALIPER FLUID REPLACEMENT AND AIR BLEEDING 7 7 7 1 ...

Page 102: ...mit Brake Pad Thickness 5 mm 0 20 2 mm 0 08 Brake Disc Thickness 4 2 mm 0 17 3 8mm 0 15 Torque Specifications Item Torque Nm Torque ft lbs except where noted Brake Arm Retaining Bolts 4 9 43 in lbs Axle Housing Flange Nuts or Brake Plate Bolts 54 40 Chain Guard Bolts 22 16 NOTE Refer to the tightening procedures in this chapter when torquing the bolts Some special procedures are used when torquing...

Page 103: ...front end of ATV off the ground far enough to remove the wheel Severe injury could occur if machine tips or falls 4 Remove the outer bearing spacer from the wheel hub 2 Remove the dust cap and cotter pin 3 Remove wheel nut and remove wheel and hub as an assembly 7 3 ...

Page 104: ...ing for wear or damage Brake Shoe Removal 9 Reinstall brake backing plate and components if previously removed 10 Using a suitable tool lift up on the spring near the retainer stud as shown and remove the spring Brake Drum Backing Plate Removal 7 Remove the backing plate assembly from the spindle shaft assembly CAUTION Spring is under tension Wear safety glasses and use caution when removing sprin...

Page 105: ...stration below as reference when reassembling the front brake components Front Brake Shoe Pad Thickness Service Limit 1 27 mm 0 05 16 Inspect oil seals and bearings for wear or damage upon assembly Replace bearings and seals if necessary 17 Install the wheel hub and tighten the front spindle nut to specification Front Wheel Spindle Nut Torque 60 Nm 44 ft lbs NOTE Perform the Brake Lever Adjustment...

Page 106: ...llow the Swing Arm Removal procedure to the point where the rear brake disc housing can be accessed NOTE You do not need to fully disassemble the rear axle swing arm to service the rear brakes 2 Inspect the brake pads contact disc surface and the axle housing seal surface for excessive wear pitting or damage Replace if necessary 7 6 ...

Page 107: ...the bleed house to bleed valve 3 Loosen the bleed valve and pump the brake lever until no more fluid flow out of the bleed valve NOTE 1 Check the fluid lever often while bleeding the brake to prevent air from being pumped into the system 2 Repeat the above procedure until air bubbles do not appear in the plastic hose 3 If air is entering the bleeder from around the bleed valve threads seal the thr...

Page 108: ... 9 IGNITION COIL TEST 8 9 CDI OUTPUT TEST USING PEAK READING ADAPTOR 8 9 PULSER COIL OUTPUT RESISTANCE TESTS 8 9 CHARGING SYSTEM 8 10 CHARGING SYSTEM TESTING 8 10 MAIN FUSE FUSE HOLDER LOCATION 8 11 VOLTAGE REGULATOR RECTIFIER 8 11 STATOR ALTERNATOR TESTS 8 11 BATTERY 8 12 BATTERY MAINTENANCE SERVICE NOTES 8 13 NEW BATTERY ACTIVATION 8 13 BATTERY REMOVAL 8 13 BATTERY CLEANING INSTALLATION 8 14 BAT...

Page 109: ...electrical problems Readings obtained with other meters may differ Pay attention to the prefix on the multimeter reading K M etc and the position of the decimal point For resistance readings isolate the component to be tested Disconnect it from the wiring harness or power supply The letter of wires color show as following B Black R Red Y Yellow W White L Blue P Pink BR Brow G Green O Orange DB Dee...

Page 110: ...y is turned to the OFF position there should no continuity between any of the wires When the key switch is turned to the position there should be continuity between the red R and brown Br wires There should also be continuity between the black B and green G wires Also be continuity between the yellow red Y R and white black WB wires Left Hand Switch Assembly The following illustration shows the in...

Page 111: ...ring harness from the stator to the running lights There should be continuity between the YE RD wire at the light connector and the YE RD wire at the Generator Stator 3 If continuity is good Perform stator resistance tests by using the resistance chart located in the wiring diagram 4 Replace Generator Stator if resistance is not within specification Headlight Lamp Replacement If the headlights do ...

Page 112: ...mp 4 Remove the lamp 5 Install new lamp s into the cover or pod and secure with retaining nut 6 Apply dielectric grease to the wire connections of the new lamp 7 Reconnect wire connections and assemble the handlebar cover or pod 8 Turn ignition key to the ON position and shift the transmission into Neutral or Reverse to verify light operation INDICATOR LAMPS Indicator Lamp Replacement 1 Remove the...

Page 113: ...er proof glue If any part of the signal is faulty the entire signal assembly must be replaced 1 Take off the front or rear signal wire plug with harness 2 Remove front signal and bracket from cab as picture 3 Remove rear signal and bracket from cab as picture 8 6 ...

Page 114: ... for continuity between the G Br wires and ground 3 Then shift the transmission into reverse and test for continuity between the B Br wires and ground In both tests you should have continuity to ground Removal 1 Remove the CVT cover The indicator switch will be visible between the drive and driven clutch Refer to CVT Chapter for CVT cover removal and installation 2 Remove the 2 screws and pull on ...

Page 115: ...lack B wire Spark plug gap incorrect Fouled spark plug Faulty spark plug cap or poor connection to high tension lead Related wiring loose disconnected shorted or corroded Engine Stop switch or ignition switch faulty Poor ignition coil ground Faulty stator measure resistance of all ignition related windings Incorrect wiring inspect color coding in connectors etc Faulty ignition coil winding measure...

Page 116: ...LIGHT SIGNAL W L IGNITION COIL DC INPUT Ignition Coil Test CDI Output Test Using Peak Reading Adaptor Re connect all wires to the CDI box Disconnect the white blue CDI output wire from ignition coil primary terminal Install the Peak Reading Adaptor to your meter and connect one meter lead to engine ground and the other to the white blue CDI Output wire at the ignition coil Set meter to read DC Vol...

Page 117: ...or rectifier and stator Using a volt meter perform a stator output test See the test procedure detailed in this chapter Does stator AC output meet specification under Stator Alternator Tests NO Perform the resistance tests detailed in this chapter under the Stator Alternator Tests If stator magnets stator coils and stator wire harness for damage Repair or replace any damaged components tests good ...

Page 118: ...multimeter to determine the condition of the stator alternator TEST 1 Measure resistance value of each stator leg 1 Measure the resistance value of the stator legs Use the following chart as a reference when testing Voltage Regulator Rectifier 1 The voltage regulator rectifier is located under the headlight of front cab on all model Ohm Test Connect Meter Leads To ΩReading Battery Charge Coil Blac...

Page 119: ...plosive gases Keep sparks flame cigarettes etc away Ventilate when charging or using in an enclosed space Always shield eyes when working near batteries KEEP OUT OF REACH OF CHILDREN CAUTION Always wear safety glasses rubber protective gloves and appropriate clothing when working with batteries IMPORTANT DO NOT activate cobra 50 ATV batteries unless they will be put into service within 30 days of ...

Page 120: ...e protective strip from the top of the battery Insert the battery electrolyte funnel into the filler holes 3 Carefully press the battery electrolyte pack onto the funnel The funnel will puncture the pack seals releasing electrolyte into the battery Allow the pack to drain for 20 minutes periodically tapping the sides to release any airlock or bubbles that may be present 4 Properly dispose of the b...

Page 121: ...nce is suspected To perform this test 1 Connect a multi tester to the battery in the same manner as was done in the battery voltage test The reading should be 12 4 volts or greater 2 Engage the electric starter and view the registered battery voltage while cranking the engine Continue the test for 15 seconds During this cranking period the observed voltage should not drop below 9 5 volts 3 If the ...

Page 122: ...ower is sent to the starter motor to crank the engine Starter Motor Service The starter motor is a complete service part If it is determined that the starter motor is the failed part replace as needed See the parts manual for correct part numbers Starter Disassembly NOTE Use only electrical contact cleaner to clean starter motor parts Other solvents may leave a residue or damage internal parts and...

Page 123: ...g 3 Remove magnet housing while holding the armature and brush holder section together Starter Brush Inspection Replacement 1 Using an Ohm meter measure the resistance between the cable terminal and the insulated brush The reading should be 3 ohms or less Measure the resistance between the cable terminal and brush housing Make sure the brush is not touching the case The reading should be infinite ...

Page 124: ...er Motor Does Not Turn Battery discharged low specific gravity Loose or faulty battery cables or corroded connections see Voltage Drop Tests Related wiring loose disconnected or corroded Poor ground connections at battery cable starter motor or starter solenoid see Voltage Drop Tests Faulty starter button Faulty ignition switch Do other systems function Faulty starter solenoid or starter motor Eng...

Page 125: ...y voltage present YES Disassemble starter motor and repair or replace as required NO At the relay connect connect one meter lead to the red wire and the other to engine ground Is battery voltage present NO Inspect battery voltage and check to see that the red wire is properly connected to the battery post YES At relay connector connect one meter lead to the green yellow wire and the other to engin...

Page 126: ...ELECTRICAL 8 19 ...

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