1. Manuals
  2. Brands
  3. Aeon Manuals
  4. Offroad Vehicle
  5. COBRA 50 2007
  6. Service manual

Aeon COBRA 50 2007 Service Manual

Hide thumbs
Table of Contents

Advertisement

Quick Links

2007 NEW COBRA 50
SERVICE MANUAL
FOREWORD
This service manual is designed primarily for use by certified Aeon Master Service
Dealer technicians in a properly equipped shop and should be kept available for
reference. All references to left and right 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 special tools. Use only the proper tools
as specified.

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the COBRA 50 2007 and is the answer not in the manual?

Questions and answers

Karl Jørgen Kristiansen
March 26, 2025

What is the new engine compression test reading with the automatic compression relief system in place?

0

Related Manuals for Aeon COBRA 50 2007

Summary of Contents for Aeon COBRA 50 2007

  • Page 1 SERVICE MANUAL FOREWORD This service manual is designed primarily for use by certified Aeon Master Service Dealer technicians in a properly equipped shop and should be kept available for reference. All references to left and right side of the vehicle are from the operator's perspective when seated in a normal riding position.

  • Page 2: Information

    UNDERSTANDING MANUAL SAFETY LABELS AND DIRECTIONS Throughout this manual, important information is brought to your attention by the following symbols: SAFETY ALERT WARNING indicates a potential hazard that may result in severe injury or death to the 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.
  • Page 3 GENERAL INFORMATION MAINTENANCE ENGINE / TRANSMISSION FUEL SYSTEM BODY / SUSPENSION / STEERING BRAKES ELECTRICAL...
  • Page 4 GENERAL INFORMATION CHAPTER 1 GENERAL INFORMATION INFORMATION ..……………..........1.2 ENGINE SERIAL NUMBER LOCATION .

  • Page 5: Engine Serial Number Location

    GENERAL INFORMATION MODEL INFORMATION VIN Identification Engine Serial Number Location Whenever corresponding about 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.
  • Page 6 GENERAL INFORMATION GENERAL SPECIFICATIONS DESCRIPTION COBRA 50 ENGINE TYPE 2-Stroke, Horizontal DISPLACEMENT 49.3 cc BORE STROKE 40*39.2 COMPRESSION RATIO 7.6:1 MAX. TORQUE 3.73 N-m/ 5724 rpm STARTING Electric/ Kicker LUBRICATION / OIL CAPACITY Oil Injection / 1 Liter TRANSMISSION Automatic (C.V.T system) TIRE FRONT 19*7-8...

  • Page 7: Vehicle Component Inspection Locations

    GENERAL INFORMATION Vehicle Component Inspection Location...

  • Page 8: Table Of Contents

    MAINTENANCE CHAPTER 2 MAINTENANCE PERIODIC MAINTENANCE CHART......... . 2.3 PERIODIC MAINTENANCE OVERVIEW.
  • Page 9 BATTERY CLEANING ..........2.17 BATTERY INSTALLATION.

  • Page 10: Periodic Maintenance Chart

    Polaris dealer. ◆ = SEVERE USE ITEM -- See Above NOTE: Inspection may reveal the need for replacement parts. Always use genuine Aeon parts. Improperly performing the procedures marked with a■ could result in component failure and lead to serious injury or death.

  • Page 11: Pre-Ride - 40 Hour Maintenance Interval

    MAINTENANCE Pre-Ride - 40 Hour Maintenance Interval Periodic Maintenance Chart Maintenance Interval (whichever comes first) ITEM Remarks Hours Calendar Check for free operation ■ Steering Pre-Ride ◆ Front- Suspension Pre-Ride Make adjustments as needed. Make adjustments as needed. ◆ Rear- Suspension Pre-Ride Make adjustments as needed.

  • Page 12: 50 - 300 Hour Maintenance Interval

    Inspect; replace as needed. ■ Front wheel bearings 100H 1500 Inspect periodically; adjust when ■ Toe adjustment parts are replaced. ■ Perform these procedures more often for vehicles subjected to severe use. ◆ Have an authorized Aeon dealer perform these services.

  • Page 13: Frame, Nuts, Bolts And Fastener Inspection

    MAINTENANCE Frame, Nuts, Bolts and Fastener Inspection Periodically inspect the torque of all fasteners in accordance with the maintenance schedule. Check that all cotter pins are in place. Refer to specific fastener torques listed in each chapter. Standard Torque Specifications The following torque specifications are to be used as a general guideline.

  • Page 14: Kick-Start Lever And Operation

    Kick-Start Lever and Operation If the battery becomes too weak to start the engine, use the kick start lever to start the engine until the battery is serviced. 1. Position the vehicle on a level surface. 2. Shift the transmission into neutral (if equipped). 3.

  • Page 15: Throttle Stop Speed Control System

    Throttle Stop Speed Control System Use the following procedure to control how far the throttle 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.

  • Page 16: Choke Cable Adjustment

    Choke Cable Adjustment Verify free play of 1.6-4.76 mm (1/16-3/16”) and smooth operation of choke cable. Adjustments to the freeplay can be made by loosening the choke cable adjustment in or out to gain the desired freeplay. If smooth choke operation is not obtainable, inspect choke cable for kinks or sharp bends in routing.

  • Page 17: Fuel Filter

    MAINTENANCE Air Screw Adjustment 1. Set idle speed to specification. Always check throttle cable freeplay after adjusting idle speed and adjust if necessary. 2. To adjust the mixture screw setting, you will need to use the Adjustment Screwdriver. Slowly turn the mixture screw clockwise until engine idle RPM begins to decrease.

  • Page 18: Carburetor Draining

    MAINTENANCE Carburetor Draining The carburetor float bowl should be drained periodically to remove accumulated moisture or sediment from the bowl, or before extended periods of storage. 1. Turn fuel valve to the ‘OFF’ position. 2. Place a container beneath the bowl drain hose. 3.

  • Page 19: Air Filter Service

    2.10 MAINTENANCE Air Filter Service 1. Release the screw and remove the cover. 2. Remove the foam air filter. 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.

  • Page 20: Engine

    2.11 MAINTENANCE ENGINE Transmission Oil Level Maintain the oil level within the safe range on the filler plug. Do not overfill. To check the oil level: 1. Position the vehicle on a level surface. 2. Remove the filler plug. 3. Check oil lever by glass widow. NOTE: Rising oil level between checks in cool weather driving, can indicate moisture collecting in the oil reservoir.

  • Page 21: Engine Mounts

    14. Stop the engine and inspect for leaks. 15. Check the oil level. Add oil as needed to bring the level to the upper mark on the window. 2.12 MAINTENANCE Engine Mounts Inspect engine mounts for cracks or damage. Engine Fastener Torque Check engine fasteners and ensure they are tight CVT Drying NOTE: If operating the ATV through water, be sure to check the CVT and other components for water...

  • Page 22: Transmission And Final Drive

    2.13 MAINTENANCE TRANSMISSION AND FINAL DRIVE Transmission Lubrication The transmission lubricant level should be checked and changed in accordance with the maintenance schedule. Remember to: • Verify the vehicle is level before proceeding. • Verify the vent hose is routed properly and is not obstructed.

  • Page 23: Drive Chain Inspection

    6. Add the recommended lubricant. Maintain the lubricant level at the bottom of the fill plug hole threads. 7. Reinstall the fill plug. Check for leaks. 2.14 MAINTENANCE Drive Chain Inspection 1. Check the amount of chain slack by moving the vehicle slightly forward to gain chain deflection.
  • Page 24 1. Loosen the four (4) rear bearing housing mount 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: Sprocket Inspection

    5. Tighten the four (4) bearing housing bolts to 43 lbs. (60 Nm) and reinstall the rear cover. 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.

  • Page 26: Battery Cleaning

    To remove the battery: Remove the seat to access the battery. 2. Loosen the bracket securing the battery in position. 3. Disconnect the black negative (-) battery cable first. 4. Disconnect the red positive (+) battery cable last. 5. Lift the battery out of the ATV. Battery Cleaning Keep the battery terminals and connections free of corrosion.

  • Page 27: Fuses / Fuse Holder Location

    Fuses / Fuse Holder Location A 7 Amp fuse protects the main electrical system on all models. See illustrations for fuse locations. Spark Plug Inspection 1. Remove spark plug high tension lead. Clean plug area so no dirt and debris can fall into engine when plug is removed. 2.

  • Page 28: Steering And Suspension

    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 technician should replace worn or damaged steering parts. Use only genuine Aeon replacement parts.

  • Page 29: Tie Rod End / Steering Inspection

    MAINTENANCE Tie Rod End / Steering Inspection 1. Elevate front end of ATV so front wheels are off the ground. Check for any looseness in front hub / wheel assembly by grasping the tire firmly at top and bottom first, and then at front and rear.

  • Page 30: Toe Adjustment

    MAINTENANCE Toe Adjustment If toe alignment is incorrect, measure the distance between vehicle center and each wheel. This will tell you which tie rod needs adjusting. NOTE: Be sure the handlebars are straight ahead before determining which tie rod(s) need adjustment.

  • Page 31: Rear Suspension Inspection

    2.21 MAINTENANCE Rear Suspension Inspection Compress and release rear suspension. Damping should be smooth throughout the range of travel. • Check all rear suspension components for wear or damage. • Inspect shock for leakage. •Inspect the rear shock and spring to ensure proper function. If the shock is leaking oil, replace it.

  • Page 32: Brake Freeplay

    2.22 MAINTENANCE Brake Freeplay Measure the free-play 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: Front Brake Adjustment

    Front Brake Adjustment 1. Position the vehicle on a level surface. 2. Shift the transmission into neutral. 3. Elevate the front of the vehicle by placing a suitable stand under the frame. The front tires should be slightly off the ground.

  • Page 34: Wheels And Tires

    WHEELS AND TIRES Wheels Inspect all wheels for runout or damage. Check wheel bolts and ensure they are tight. Do not over tighten the wheel bolts. Wheel, Hub and Spindle Torque Table Item Specification Front wheel bolts 30Nm( 22ft. lbs) Rear wheel bolts 30Nm( 22ft.

  • Page 35: Tire Pressure

    MAINTENANCE Tire Pressure Tire Pressure Inspection (PSI - Cold) Front Rear 5 psi 5 psi Tire Inspection 2.25...
  • Page 36 CVT SYSTEM CHAPTER 3 CVT SYSTEM CVT SYSTEM ............3.2 CVT MAINTENANCE / INSPECTION.

  • Page 37: Cvt System

    During the high. development of a Aeon ATV, the CVT system is matched first Driven Clutch Operation to the engine power curve; then to average riding conditions CVT driven clutches primarily sense torque, but also react to and the vehicle’s intended usage.

  • Page 38: Cvt System Drying

    CVT SYSTEM CVT System Drying NOTE: If operating the ATV through water, be sure to check the CVT cover and other ATV components for water ingestion. The ATV should be checked immediately. Refer to Owner’s Manual for Safe Riding Tips. 1.

  • Page 39: Clutch Cover Removal

    CVT SYSTEM Clutch Cover Removal Drive Belt Removal 1. Remove the left footrest. 1. Remove O-ring and nut from driven clutch. 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.

  • Page 40: Drive Clutch Service

    CVT SYSTEM DRIVE CLUTCH SERVICE Drive Clutch Disassembly and Inspection 1. Remove outer drive clutch sheave and drive belt. Note parts 6. Inspect sheave faces (E) for grooves or wear. Check assembly order. bushings (F) and seals in the moveable sheave. The sleeve 2.

  • Page 41: Drive Clutch Assembly

    CVT SYSTEM Drive Clutch Assembly 5. Open the sheaves of the secondary clutch and push the belt down between the sheaves. 1. Apply a very light film of grease to the seal lips and drive 6. Install the driven clutch on the transmission input shaft, clutch sleeve.

  • Page 42: Driven Clutch Service

    CVT SYSTEM DRIVEN CLUTCH SERVICE 5. Remove the outer roller pin cover by turning and pulling up Driven Clutch Disassembly and Inspection on the cover. Replace the two sealing O-rings. 1. Remove driven clutch assembly by removing O-ring and nut. 2.
  • Page 43 CVT SYSTEM 7. To replace friction shoes, remove E-clips that retain the 9. Use a vernier caliper to check the length of the compression backing plate. Use a suitable tool to remove and install the spring. At full extension, the measurement should be no less return springs connecting the shoes, using care not to stretch than 69.7 mm.( 2.74”) .

  • Page 44: Driven Clutch Assembly

    CVT SYSTEM Driven Clutch Assembly 3. Install the drive belt on driven clutch and move belt as far 1. Insert new seals into the outer sheave assembly. Fill the outer into the sheaves as possible. sheave cavity with fresh grease and slide onto the inner sheave 4.

  • Page 45: Engine / Transmission

    ENGINE / TRANSMISSION CHAPTER 4 ENGINE / TRANSMISSION ENGINE SERVICE ............4.3 ENGINE EXPLODED VIEWS &...

  • Page 46: Engine Service

    ENGINE / TRANSMISSION ENGINE SERVICE Engine Exploded Views & Torque Values...
  • Page 47 ENGINE / TRANSMISSION Engine Exploded Views & Torque Values...

  • Page 48: Accessible Components

    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.

  • Page 49: Engine Removal

    ENGINE / TRANSMISSION Engine Removal 1. Clean the ATV and work area thoroughly. 2. Remove seat. 3. Remove front cab and foot rests. 4. Disconnect battery cables. 5. Drain engine oil and / or transmission oil as required. 6. Disconnect or remove from RIGHT Side: •...

  • Page 50: Engine Lubrication

    ENGINE / TRANSMISSION Engine Lubrication Oil Type:** 2T/ LST Capacity: Approximately 1000ml (30 oz.) Transmission Lubrication Oil Type: 80W/ 90 API Capacity: Approximately 350 ml (12 oz.) Drain Plug (Transmission): 16 ft. lbs. (21.5 Nm) ENGINE DISASSEMBLY CYLINDER HEAD DISASSEMBLY Loosen all four bolts of cylinder head cover.
  • Page 51 ENGINE / TRANSMISSION CYLINDER HEAD WARP INSPECTION Lay a straight across the surface of the head at several difference points and measure warpage by in serting a feeler gauge between the straight edge and the cylinder head surface. If warpage exceeds the service limit, replace the cylinder head. Cylinder head warp limit: 0.05mm Combustion chamber inspection Clean all accumulated carbon deposite from com bustion...

  • Page 52: Cylinder Inspection

    ENGINE / TRANSMISSION CYLINDER INSPECTION Maximum cylinder wear occurs at the very top of top ring travel. Minimum wear occurs below ring travel. Failure to measure the cylinder at these point may result in a faulty decision regarding the suitability of the cylinder for continued use. Using an inside micrometer or dial bore gauge.

  • Page 53: Piston Inspection

    ENGINE / TRANSMISSION • Release the hone at regular intervals and inspect the bore to determine if it has been sufficiently deglazed, and to check for correct cross-hatch. NOTE: Do not allow cylinder to heat up during honing. IMPORTANT: Clean the Cylinder After Honing Clean cylinder thoroughly after honing to remove all grit material.

  • Page 54: Piston Ring Installed Gap

    ENGINE / TRANSMISSION 7. Measure connecting rod small end ID. Replace crankshaft 8. Measure piston ring to groove clearance by placing the ring if connecting rod small end is out-of-round. in the ring land and measuring with a thickness gauge. Replace piston and rings if ring-to-groove clearance exceeds service limit.

  • Page 55: Flywheel Removal / Inspection

    ENGINE / TRANSMISSION Flywheel Removal / Inspection 1. Remove the flywheel cover, the flywheel nut, and washer. Install flywheel puller and remove flywheel. CAUTION: Do not hammer or strike the tool or crankshaft may be damaged. Stator Removal Stator Inspection 1.

  • Page 56: Oil Pump Removal

    ENGINE / TRANSMISSION Stator installation Install stator wire into crankcase. stator screws (A) and pulse coil screws (B). Fasten Place the fly wheel then washer in crankshaft. fasten nut onto fly wheel. Oil Pump Removal 4. Take off the bolts then remove the oil pump. 1.
  • Page 57 ENGINE / TRANSMISSION 6. Take off wave washer then remove gear. Oil pump body inspection Inspect the oil pump outside diameter by caliper. Wave washer Oil pump OD. Limit: 21.98mm. min. 7. Remove mount bracket then circlip and dowel pin. Oil tube inspection Inspect the tube leaking and broken.

  • Page 58: Crankcase Disassembly

    ENGINE / TRANSMISSION Crankshaft Inspection Crankcase Disassembly 1. Inspect the crankshaft main bearings and cam chain NOTE: Engine must be removed to perform sprocket for wear or damage. crankcase or crankshaft service. NOTE: Due to extremely close tolerances and 1. Remove engine, cylinder, piston, and stator assembly. minimal wear, the bearings must be inspected 2.

  • Page 59: Transmission

    ENGINE / TRANSMISSION TRANSMISSION 7. Remove the shift shaft by pulling straight outward. DO Transmission Disassembly and Inspection NOT LOSE the spring and plunger on the inner end of NOTE: Engine removal is not required to service the shaft. This plunger contacts the gear position switch. transmission components.
  • Page 60 ENGINE / TRANSMISSION 10. Remove the counter shaft. 13. Loosen 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.

  • Page 61: Transmission Inspection

    ENGINE / TRANSMISSION Transmission Inspection 5. Inspect sliding gear dogs and dog slots in the mating gears NOTE: Always wear the appropriate protective gear and (F) for wear or damage. The edges of dogs and slots should use caution when operating a press. be square and not rounded.
  • Page 62 ENGINE / TRANSMISSION Shaft Disassembly Shaft Assembly 8. If radial movement in Step 7 was excessive, support the 11. Assemble the reverse gear , washer, a new snap ring, and forward gear and press the shaft through the spacer to the sliding gear on the shaft.

  • Page 63: Transmission Assembly

    ENGINE / TRANSMISSION Transmission Assembly IMPORTANT: To reassemble the transmission, reverse 2. Check transmission operation before final assembly, and the disassembly procedure, refer to exploded view, and after installing outer cover and output shaft. review the following information and special notes. 1.

  • Page 64: Starter Drive Mechanism (Electric)

    ENGINE / TRANSMISSION Starter Drive Mechanism (Electric) 6. Before removing the starter one-way clutch / gear 1. Remove CVT cover. See “Clutch Cover Removal” in assembly, inspect the gear operation. The ring gear should Chapter 3. rotate smoothly and freely in a clockwise direction (A). 2.
  • Page 65 ENGINE / TRANSMISSION Inspect the surface of the gear hub ( 4 ). It must be smooth and free of surface damage. Be sure bearing in hub turns smoothly. Remove the rollers, plungers and springs of one way (5). Replace assembly if damaged or worn. Inspect the splines on the one-way clutch for wear or damage.

  • Page 66: Kick Start

    ENGINE / TRANSMISSION KICK START 4. Mark the shaft at the opening of the kick start pedal , or Kick Start Disassembly / Inspection note position of kick start pedal before removing. The kick start spring is under tension. Wear face protection during disassembly and assembly of the kick start mechanism.

  • Page 67: Kick Start Assembly

    ENGINE / TRANSMISSION Kick Start Assembly 7. Hold shaft in place so spring does not disengage, and turn 1. Secure cover lightly in a vise. Protect the surface cover over. of the cover from damage. 8. Install retaining ring on shaft. 2.

  • Page 68: Troubleshooting

    ENGINE / TRANSMISSION TROUBLESHOOTING Engine Runs But Will Not Idle Spark Plug Fouling • Carburetor pilot (idle) circuit restricted or blocked • Spark plug cap loose or faulty • Carburetor misadjusted • Choke cable adjustment, cable or shaft sticking • Choke not adjusted properly •...
  • Page 69 ENGINE / TRANSMISSION Transmission Piston Failure - Scoring • Lack of lubrication Gear Will Not Engage • Dirt entering engine through cracks in air filter or ducts • Shift arm indexed incorrectly (hits bracket) • Engine oil dirty or contaminated •...
  • Page 70 FUEL SYSTEM CHAPTER 5 FUEL SYSTEM CARBURETION SYSTEM..........5.2 CARBURETOR FUNCTION.

  • Page 71: Carburetor Function

    FUEL SYSTEM Carburetor Function Carburetor Component Function System Main Main Main Components Function Affect Gasoline is extremely flammable and explosive under Float System Inlet Pipe, Needle Maintains All systems; all certain conditions. Level Control) and Seat, Float specified fuel throttle ranges Always stop the engine and refuel outdoors or in a well level in float ventilated area.

  • Page 72: Carburetion Specifications

    FUEL SYSTEM Carburetion Specifications CARBURETOR OPERATION Operation Overview COBRA 100 SUNWORLD The engine of a vehicle is operated under a wide range of Pilot Air Screw 1 1/4 conditions, from idling with the throttle valve remaining almost closed, to full load or maximum output with the throttle Needle H68T valve fully opened.

  • Page 73: Float System

    FUEL SYSTEM Float System Air Mixture Screw The float system is designed to maintain a constant height of The pilot mixture screw controls the fuel mixture from idle to gasoline during operation. When the fuel flowing from the fuel low speeds. The tapered tip of the mixture screw projects into pump into the float chamber through the needle valve reaches the fuel mixture passage leading to the pilot jet air bleeds.

  • Page 74: Air / Fuel Mixture Ratio

    FUEL SYSTEM Air / Fuel Mixture Ratio Jet Needle The jet needle has five adjustment grooves cut into the upper portion, and is tapered from approximately the middle of the needle to the lower end. The top is fixed to the center of the throttle valve by the needle clip, and the tapered end extends into the needle jet.

  • Page 75: Throttle Opening Vs. Fuel Flow

    FUEL SYSTEM Throttle Opening vs. Fuel Flow Main Jet In a full throttle condition the cross sectioned area between the When the throttle opening becomes greater and the area jet needle and the needle jet is larger than the cross sectioned between the needle jet and jet needle increases, fuel flow is area of the main jet.

  • Page 76: Pilot System (Idle - 3/8 Throttle)

    FUEL SYSTEM Pilot System (Idle - 3/8 Throttle) Slide Cutaway (1/8 - 3/8 Throttle) The pilot system’s main function is to meter fuel at idle and Throttle valve cutaway effect is most noticeable at 1/4 throttle low speed driving. Though its main function is to supply fuel opening.

  • Page 77: Jet Needle / Needle Jet (3/8 - 3/4 Throttle)

    FUEL SYSTEM Main System (3/4 to Full Throttle) Jet Needle / Needle Jet (3/8 - 3/4 Throttle) The main system is designed for delivering fuel between low The jet needle and needle jet have the most effect between 3/8 speed and high speed operation. This system is made up of the and 3/4 throttle opening.

  • Page 78: Fuel Delivery

    FUEL SYSTEM CARBURETOR SERVICE Fuel Delivery Carburetor Float Bowl Draining The throttle opening chart below demonstrates component relationship to fuel flow versus throttle valve opening. The carburetor float bowl should be drained periodically to The pilot system’s main function is that of a low speed jet. Its remove moisture or sediment from the bowl, or before most effective range of fuel delivery is from idle to extended periods of storage.

  • Page 79: Carburetor Removal - General

    FUEL SYSTEM Carburetor Removal - General Carburetor Disassembly The following procedure is provided to use as a reference Use the following procedure to disassemble the carburetor. when removing the carburetor from vehicle. Some steps may 1. Remove the (4) float bowl screws and float bowl. differ slightly between models.
  • Page 80 5.10 FUEL SYSTEM 4. Remove the pilot jet , main jet , and from the carb body. 2. Remove cable with valve from the carb body. 5. Note the position of both the air mixture screw and idle 3. Loosen the choke seat screw. speed adjustment screw and remove both from the carb body.

  • Page 81: Carburetor Cleaning

    5.11 FUEL SYSTEM Carburetor Cleaning Carburetor Inspection 1. Remove the carburetor slide assembly. Disassemble the components and inspect for wear. Inspect slide needle and look for discoloration, shiny spots, or an area that looks different Protect eyes from contact with cleaner. Take appropriate than the rest of the needle.

  • Page 82: Float Height Adjustment

    5.12 FUEL SYSTEM Float Height Adjustment 3. Inspect the idle speed adjust screw tip for flat spots and the 1. Place the carburetor at a level position to remove weight pilot mixture screw tip for damage. If any damage is from float arm.

  • Page 83: Carburetor Assembly

    5.13 FUEL SYSTEM Carburetor Assembly 1. Replace parts in proper order. Refer to the parts exploded view or “Disassembly” steps for further detail 2. Install the pilot air mixture screw, spring, washer, and Oring as an assembly (Mikuni Only). Lubricate the O-Ring with oil or light grease before installation.
  • Page 84 5.14 FUEL SYSTEM Fuel and oil tank location...

  • Page 85: Fuel Tank Removal

    5.15 FUEL SYSTEM Fuel Tank Removal See Chapter 6 for body removal procedures to gain access the fuel tank. 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.
  • Page 86 3. Carefully lift up on the fuel tank. 4. Place a shop rag or towel underneath the tank and remove both fuel lines from the tank. 3. Carefully lift up on the oil tank. 4. Remove the oil line and oil gauge from the tank. 5.

  • Page 87: Air Cleaner Exploded View

    AIR CLEANER EXPLODED VIEW 5.17 FUEL SYSTEM...

  • Page 88: Air Cleaner Removal

    Air Cleaner Removal 1. Release the screw and remove the cover. 2. Remove the foam air filter. 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.

  • Page 89: Troubleshooting

    TROUBLESHOOTING Poor Idle Fuel Starvation / Lean Mixture Idle Too High Symptoms: Hard start or no start, bog, backfire, popping • Idle adjusted improperly / air mixture screw damaged through intake / exhaust, hesitation, detonation, low power, • Throttle cable sticking, improperly adjusted, routed spark plug erosion, engine runs hot, surging, high idle, idle incorrectly speed erratic.

  • Page 90: Body / Suspension / Steering

    BODY / SUSPENSION / STEERING CHAPTER 6 BODY / SUSPENSION / STEERING GENERAL INFORMATION ..........6.2 TORQUE SPECIFICATIONS .

  • Page 91: Torque Specifications

    BODY / SUSPENSION / STEERING BODY REMOVAL Torque Specifications 1. Lift up on the seat latch and remove the seat. 2. Remove the 4 screws of the fuel tank cover. Fastener Torque Suspension Fasteners A–Arm Attaching Bolt 34 Nm (25 ft. lbs.) Shock Mounting Bolts Front: 34 Nm (25 ft.
  • Page 92 BODY / SUSPENSION / STEERING 5. Remove the 2 bolts attaching the body to the footwells 9. Disconnect both front indicator plugs. on each side. 6. Remove the 8 screws attaching front and rear cabs to the footwells on each side. 7.

  • Page 93: Front Bumper Removal / Installation

    BODY / SUSPENSION / STEERING Front Bumper Removal / Installation 15. Cut off the straps of rear indicators then disconnect 1. Remove the (4) mounting bolts retaining the front bumper indicator plugs with main harness. and remove the bumper from the ATV. 16.Remove Rear cab from cab.

  • Page 94: Suspension

    BODY / SUSPENSION / STEERING SUSPENSION Front Shock Removal 1. Elevate front end of the ATV off the ground to remove shock spring tension. Front Shock Mounting Bolt Torque: 34 Nm (25 ft. lbs.) Severe injury could occur if machine tips or falls. 2.

  • Page 95: Rear Shock Removal

    BODY / SUSPENSION / STEERING Rear Shock Removal 1. Elevate rear end of the ATV off the ground to remove shock spring tension. Severe injury 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 swing arm.

  • Page 96: Front A-Arm

    BODY / SUSPENSION / STEERING FRONT A-ARM A-arm Exploded View A-arm Replacement 4. Remove the cotter pin from the upper spindle castle nut and 1. Elevate front end of ATV off the ground far enough to remove the nut. remove the wheel. Severe injury could occur if machine tips or falls.

  • Page 97: Swing Arm

    BODY / SUSPENSION / STEERING SWING ARM 6. Remove the lower shock mounting fastener and the inner Removal A-arm fasteners. 1. Elevate rear end of ATV off the ground far enough to remove the rear wheel(s). Severe injury could occur if machine tips or falls. 2.

  • Page 98: Brakes

    BODY / SUSPENSION / STEERING 4. Take off the master link from chain then remove chain from 8. Remove disc from rear axle. sprocket. 5. Take off 2 bolts from caliper then remove caliper. 9. Remove 4 axle hub bolts from swing arm. 6.

  • Page 99: Steering

    BODY / SUSPENSION / STEERING STEERING 2. Remove the upper steering post mounting bolts. Steering Assembly Exploded View Steering Post Removal 3. Remove the inner tie-rod nuts and the steering post nut. 1. Remove handlebar fasteners and retainer block. 4. Carefully remove the steering post from the ATV. 5.

  • Page 100: Handlebar

    BODY / SUSPENSION / STEERING HANDLEBAR DECAL REPLACEMENT The following procedure involves the use of an open flame. Perform this procedure in a well ventilated area, away from gasoline or other flammable materials. Be sure the area to be flame treated is clean and free of gasoline or flammable residue.
  • Page 101 BRAKES CHAPTER 7 BRAKES SPECIFICATIONS............7.2 GENERAL SPECIFICATIONS .

  • Page 102: Specifications

    BRAKES SPECIFICATIONS General Specifications Front Brake Drum Item Standard Service Limit Brake Shoe Thickness 2.54 mm (0.10”) 1.27 mm (0.05”) Brake Drum Inner Diameter 85.09 mm (3.35") 84.33 mm (3.32") Rear Brake Disc Item Standard Service Limit Brake Pad Thickness 5 mm (0.20”) 2 mm (0.08") Brake Disc Thickness...

  • Page 103: Front Brakes

    BRAKES FRONT BRAKES Exploded View Front Brake Service 4. Remove the outer bearing spacer from the wheel hub. 1. Elevate front end of ATV off the ground far enough to remove the wheel. Severe injury could occur if machine tips or falls. 2.
  • Page 104 BRAKES 5. Inspect the outer seal and outer bearing for wear or damage. 8. Inspect spindle shaft surface for pitting or other damage. Replace spindle assembly if necessary. Brake Shoe Removal 6. Flip the wheel hub and inspect the inner seal and inner 9.
  • Page 105 BRAKES 11. Slide brake shoes off retainer stud and remove from 13. Inspect the shoe retainer stud and brake cam for wear or backing plate. damage. 12. Inspect the brake shoe pad material. Replace if worn Brake Assembly beyond specification. 14.

  • Page 106: Rear Brake Service

    BRAKES 2. Inspect the brake pads contact disc surface and the axle Rear Brake Service housing seal surface for excessive wear, pitting, or damage. NOTE: Follow the “Swing Arm Removal” procedure Replace if necessary. outlined in Chapter 6 to access the rear brake components.

  • Page 107: Rear Caliper Fluid Replacement And Air Bleeding

    BRAKES Rear caliper fluid filling/ bleeding Close the bleed valve Fill the master cylinder with DOT 4 brake fluid. Rear Brake Pad Thickness: Connect a commercially available brake bleeder to the Service Limit: 0.08” (2 mm) bleed valve. Pump the brake bleeder and loosen bleed valve. Add brake fluid when the fluid lever in the master cylinder is low.
  • Page 108 ELECTRICAL CHAPTER 8 ELECTRICAL GENERAL INFORMATION ..........8.2 ELECTRICAL SYSTEM SERVICE NOTES .

  • Page 109: General Information

    ELECTRICAL GENERAL INFORMATION SWITCHES AND CONTROLS Electrical System Service Notes Reference the following notes when diagnosing electrical Brake Lever Switches problems. Each brake lever utilizes an electrical brake switch that sends • The ignition system timing is non-adjustable. The voltage to activate the starter relay and brake light. specifications in Chapter 1 are intended for reference only.

  • Page 110: Key Switch

    ELECTRICAL Key Switch When the key switch is turned to the “ON” position, there should be continuity between the red (R) and brown (Br) The key switch can be tested with an ohm meter. wires. There should also be continuity between the black (B) and green (G) wires.

  • Page 111: Headlights

    ELECTRICAL HEADLIGHTS 2. Remove the socket rubber seal. The headlights are powered by an AC current from the Generator / Stator. When headlight switch on but working, perform the following: 1. Disconnect the harness from the faulty light. 2. Using a Volt Ohm Meter, measure the AC voltage between the yellow red (YE/RD) and black (BK) wires.

  • Page 112: Tail Light

    ELECTRICAL TAIL LIGHT 3. Remove the nut from the backside of the indicator lamp. Tail Light Lamp Replacement If the tail light lamp does not work, the lamp may need to be replaced. 1. Remove the two screws securing the lens cover. Remove the lens cover.
  • Page 113 ELECTRICAL Signal Replacement The 4 signals are sealed by water 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.

  • Page 114: Transmission Switch

    ELECTRICAL TRANSMISSION SWITCH Transmission Switch - Circuit Breakout Testing Removal 1. With the switch installed, use an ohmmeter to test continuity 1. Remove the CVT cover. The indicator switch will be visible between the switch leads and engine ground. between the drive and driven clutch. Refer to CVT 2.

  • Page 115: Installation

    ELECTRICAL IGNITION SYSTEM 3. Inspect the shift indicator contacts, shift drum, pin and spring. Overview Verify the pin is not sticking in the drum or is damaged. Replace any worn or damaged components. The Cobra 50 ATV ignition system consists of a simple magnetodriven system that includes a stator Pulser Coil, CDI Box, Ignition Coil and related wiring / connectors.

  • Page 116: Rpm Ignition Limiter Functions

    ELECTRICAL RPM Ignition Limiter Functions CDI WIRES NOTE: The CDI box reads the RPM signal from the PLUG COLOR DECCRIPTION stator. The CDI box acts as a limiter by retarding the KEY SWITCH “OFF” SIGNAL INPUT. ignition timing if RPM reaches the specified limit. In FLYWHEEL IGNITION ANGLE SIGNAL 3-WIRE reverse gear, the CDI box retards ignition timing and...

  • Page 117: Charging System

    ELECTRICAL CHARGING SYSTEM Charging System Testing Whenever charging system problems are suspected, proceed with the following system checks: Using a volt meter, set it to read D.C. volts, Remove the battery and properly service. measure the battery open circuit voltage Reinstall the fully charged battery or a fully (across the positive and negative posts).

  • Page 118: Main Fuse / Fuse Holder Location

    ELECTRICAL Main Fuse / Fuse Holder Location 2. If a problem exists with the charging system, test the A 7 Amp fuse protects the main electrical system on all components around the regulator/rectifier to isolate the models. See illustrations for fuse locations. component.

  • Page 119: Battery

    ELECTRICAL BATTERY Battery Maintenance Service Notes Battery electrolyte is poisonous. It contains sulfuric acid. Serious burns can result from contact with skin, eyes or clothing. Antidote: External: Flush with water. Internal: Drink large quantities of water or milk. Follow with milk of magnesia, beaten egg, or vegetable AC Output Test Connect AC Reading...

  • Page 120: New Battery Activation

    ELECTRICAL New Battery Activation Battery Removal Battery electrolyte is poisonous. It contains sulfuric acid. Improperly connecting or disconnecting battery cables Serious burns can result from contact with skin, eyes or can result in an explosion and cause serious injury or clothing.

  • Page 121: Battery Cleaning / Installation

    ELECTRICAL Battery Cleaning 2. Engage the electric starter and view the registered battery Keep the battery terminals and connections free of corrosion. voltage while cranking the engine. Continue the test for 15 If cleaning is necessary, remove the corrosion with a stiff wire seconds.

  • Page 122: Battery Storage

    ELECTRICAL Battery Storage Starter Motor Service Whenever the vehicle is not used for a period of three The starter motor is a complete service part. If it is determined months or more, remove the battery from the vehicle, ensure that the starter motor is the failed part, replace as needed. See the that it's fully charged, and store it out of the sun in a cool, parts manual for correct part numbers.

  • Page 123: Starter Brush Inspection / Replacement

    ELECTRICAL 2. Remove the brush plate and brushes. Measure the brush 2. Remove the 2 screws and washers. length and replace if worn past the service limit. Brush Length Service Limit 5 mm (0.20“) 3. Inspect the surface of the commutator for wear or discoloration.

  • Page 124: Starter Reassembly

    ELECTRICAL Voltage Drop Test 3. Measure the resistance between each commutator segment and the armature shaft. The reading should be infinite. (no The Voltage Drop Test is used to test for bad connections. continuity) When performing the test, you are testing the amount of voltage drop through the connection.

  • Page 125: Starter System Testing

    ELECTRICAL Starter System Testing Condition: Starter motor fails to turn engine. NOTE: Make sure engine crankshaft is free to turn before proceeding with dynamictesting of starter system. A digital multitester must be used for this test. Locate the starter relay see “ starter relay”...
  • Page 126 ELECTRICAL 8.19...

Table of Contents

Save PDF