KYMCO SERVICE MANUAL VENOX 250 KYMCO Overseas Sales Division Overseas Service Department...
PREFACE This Service Manual describes the technical features and servicing procedures for the KYMCO VENOX 250. In this manual, many illustrations and drawings are used to help servicemen have better understanding. Section 2 contains the service precautions for all operations and troubleshooting stated in this manual.
. GENERAL INFORMATION VENOX __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ GENERAL INFORMATION __________________________________________________________________________________ ENGINE SERIAL NUMBER/IDENTIFICATION......1- 1 SPECIFICATIONS ................1- 2 SERVICE PRECAUTIONS..............1- 3 SERVICE INFORMATION ..............1-10 TORQUE VALUES ................1-12 SPECIAL TOOLS ................1-14 LUBRICATION POINTS ..............1-16 WIRING DIAGRAM ................
. GENERAL INFORMATION VENOX ENGINE SERIAL NUMBER/IDENTIFICATION Location of Frame Serial Number Vehicle Identification Serial Number Location of Engine Serial Number...
. GENERAL INFORMATION VENOX SPECIFICATIONS Air cleaner type Paper element Motorcycle name & Model No. VENOX 250 Fuel capacity 14 liter Chassis name & Model No. RA50AA Type Overall length (mm) 2325 Main Jet NO Front:112 Rear:108 Overall width (mm) φ30 equivalent...
. GENERAL INFORMATION VENOX SERVICE PRECAUTIONS Make sure to install new gaskets, O-rings, circlips, cotter pins, etc. when reassembling. When tightening bolts or nuts, begin with larger-diameter to smaller ones at several times, and tighten to the specified torque diagonally. Use genuine parts and lubricants.
. GENERAL INFORMATION VENOX Apply or add designated greases and lubricants to the specified lubrication points. After reassembly, check all parts for proper tightening and operation. When two persons work together, pay attention to the mutual working safety. Disconnect the battery negative (-) terminal before operation.
. GENERAL INFORMATION VENOX If the fuse is burned out, find the cause and repair it. Replace it with a new one according to the specified capacity. Confirm Capacity After operation, terminal caps shall be installed securely. When taking out the connector, the lock on the connector shall be released before operation.
. GENERAL INFORMATION VENOX The connector shall be inserted completely. If the double connector has a lock, lock it at the correct position. Snapping! Check if there is any loose wire. Check the double connector cover for proper coverage and installation. Before connecting a terminal, check for damaged terminal cover or loose negative terminal.
. GENERAL INFORMATION VENOX After clamping, check each wire to make sure it is secure. Do not squeeze wires against the weld or its clamp. After clamping, check each harness to make sure that it is not interfering with any moving or sliding parts.
. GENERAL INFORMATION VENOX Route harnesses so they are neither pulled tight nor have excessive slack. Do not pull too tight! Protect wires and harnesses with electrical tape or tube if they contact a sharp edge or corner. When rubber protecting cover is used to protect the wire harnesses, it shall be installed securely.
. GENERAL INFORMATION VENOX After routing, check that the wire harnesses are not twisted or kinked. Wire harnesses routed along with handlebar should not be pulled tight, have excessive slack or interfere with adjacent or surrounding parts in all steering positions.
. GENERAL INFORMATION VENOX Symbols: The following symbols represent the servicing methods and cautions included in this service manual. : Apply engine oil to the specified points. (Use the designated engine oil for lubrication.) Engine Oil : Apply grease for lubrication. : Caution Grease Special...
. GENERAL INFORMATION VENOX SERVICE INFORMATION ENGINE Standard (mm) Service Limit (mm) Item Venox 250 Venox 250 ⎯ ⎯ Cylinder head warpage 57.975～57.99 57.81 Piston O.D.(10mm from bottom of piston skirt) 0.01～0.35 0.35 Cylinder-to- piston clearance 16.000～16.006 16.06 Piston pin hole I.D.
. GENERAL INFORMATION VENOX FRAME Standard (mm) Service Limit (mm) Item Venox 250 Venox 250 Axle shaft runout 0.3/100mm Radial Front wheel rim runout Axial ⎯ ⎯ Front shock absorber spring free length Rear wheel rim runout Brake drum I.D.
. GENERAL INFORMATION VENOX TROUBLESHOOTING ENGINE WILL NOT START OR IS HARD TO START Inspection/Adjustment Probable Cause Symptom Check if fuel reaches carburetor by loosening drain screw Empty fuel tank Clogged fuel line between fuel tank and carburetor Clogged float valve Clogged fuel filter Fuel does not Fuel reaches...
. GENERAL INFORMATION VENOX ENGINE STOPS IMMEDIATELY AFTER IT STARTS Inspection/Adjustment Symptom Probable Cause Check if fuel reaches carburetor by loosening drain screw Empty fuel tank Fuel reaches Fuel does not Clogged float valve carburetor reach carburetor Clogged fuel filter Remove spark plug Plug not fouled or Plug fouled or...
. GENERAL INFORMATION VENOX Symptom Inspection/Adjustment Probable Cause Check carburetor insulator rubber for air leaks. Carburetor not securely tightened No air leak Air leaks Faulty intake manifold gasket Deformed or broken carburetor O-ring 1-24...
. GENERAL INFORMATION VENOX POOR PERFORMANCE (ENGINE LACKS POWER) Symptom Inspection/Adjustment Probable Cause Start engine and accelerate lightly for observation Clogged air cleaner Poor fuel flow (Restricted) Engine speed Engine speed does not Clogged fuel tank cap breather hole increases increase sufficiently Clogged exhaust muffler Carburetor fuel level too low...
. GENERAL INFORMATION VENOX POOR PERFORMANCE (ESPECIALLY AT IDLE AND LOW SPEEDS) Inspection/Adjustment Symptom Probable Cause Check ignition timing Faulty CDI unit Correct Incorrect Faulty A.C. generator Check carburetor pilot screw adjustment Mixture too lean (turn screw in) Correctly adjusted Incorrectly adjusted Mixture too rich (turn screw out)
. GENERAL INFORMATION VENOX POOR PERFORMANCE (AT HIGH SPEED) Inspection/Adjustment Symptom Probable Cause Check ignition timing Faulty CDI unit Correct Incorrect Loose A.C. generator stator Faulty A.C. generator Check valve clearance Improperly adjusted valve clearance Correct Incorrect Worn valve seat Check fuel tank for fuel supply Empty fuel tank...
. GENERAL INFORMATION VENOX STARTER MOTOR 1. Starter motor won‘t turn Symptom Inspection/Adjustment Probable Cause Check operation of stop switch by applying brake Burned out fuse Weak or dead battery Stoplight does not Stoplight comes on Faulty stop switch come on Loose or disconnected connector Check battery circuit Broken or shorted ignition...
. GENERAL INFORMATION VENOX STEERING HANDLEBAR DOES NOT TRACK STRAIGHT Symptom Probable Cause (Front and rear tire pressures are normal) Steering stem nut too tight Steering is heavy Broken steering steel balls Excessive wheel bearing play Front or rear wheel is Bent rim wobbling Loose axle nut...
. GENERAL INFORMATION VENOX POOR SUSPENSION PERFORMANCE Symptom Probable Cause (Front and rear tire pressures are normal) Weak shock spring Suspension is too soft Excessive load Shock damper oil leaking Bent fork tube or damper rod Suspension is too hard Fork slider and tube binding Fork tube and spring binding Suspension is noisy...
. GENERAL INFORMATION VENOX FUEL GAUGE 1. Pointer does not register correctly (Ignition switch ON) Inspection/Adjustment Symptom Probable Cause Check battery circuit by operating turn signals Burned out fuse Weak or dead battery Signals operate Signals dim, remain Faulty ignition switch properly on or don‘t operate Loose or disconnected connector...
. GENERAL INFORMATION VENOX POOR CHARGING (BATTERY OVER DISCHARGING OR OVERCHARGING) Undercharging Inspection/Adjustment Symptom Probable Cause Start engine and test limit voltage between battery terminals Dead battery Voltage does not Normal voltage increase Faulty battery Measure resistance between AC generator coil terminals Faulty coil Normal...
. GENERAL INFORMATION VENOX NO SPARK AT SPARK PLUG Inspection/Adjustment Symptom Probable Cause Replace with a new spark plug and inspect again Weak or no spark Good spark Faulty old spark plug Check spark plug cap and ignition coil wire for loose connection Not loose Loose...
. INSPECTION/ADJUSTMENT VENOX SERVICE INFORMATION GENERAL WARNING •Before running the engine, make sure that the working area is well-ventilated. Never run the engine in a closed area. The exhaust contains poisonous carbon monoxide gas which may cause death to people. •Gasoline is extremely flammable and is explosive under some conditions.
. INSPECTION/ADJUSTMENT VENOX MAINTENANCE SCHEDULE In order to have a safe riding, maintain good performance, prolong the motorcycle service life and reduce pollution, make sure to perform the periodic inspection and maintenance. I: Inspect and clean, lubricate, refill, repair or replace if necessary. A: Adjust C: Clean R: Replace T: Tighten Regular Service Mileage (km) Whichever...
. INSPECTION/ADJUSTMENT VENOX BRAKE SYSTEM BRAKE LEVER & PEDAL Free Play Measure the rear brake pedal free plays. Free Play: Rear: 20～30mm Adjusting Nut If the free plays do not fall within the limits, adjust by turning the adjusting nuts. Adjusting Nut If the pedal height is unsuitable, turning the adjusting nut.
Check the tire pressure. Tire pressure should be checked when the tires are cold. TIRE PRESSURE 1 Rider 2 Riders Front 2.0 kg/cm² 2.0 kg/cm² Rear 2.0 kg/cm² 2.25 kg/cm² TIRE SIZE Model VENOX 250 Item Front 120/80–17 Rear 150/80-15...
. INSPECTION/ADJUSTMENT VENOX Bolts Check the front and rear axle nuts for looseness. If the axle nuts are loose, tighten them to their specified torques. Torques: Front : 6.0～8.0kg-m Rear : 8.0～10.0kg-m Axie Nut “T” Mark SUSPENSION FRONT Fully apply the front brake lever and check the action of the front shock absorbers by compressing them several times.
. INSPECTION/ADJUSTMENT VENOX STEERING HANDLEBAR Check that the control cables do not interfere with handlebar rotation. Raise the front wheel off the ground and check that the steering handlebar rotates freely. If the handlebar moves unevenly, binds, or has vertical movement, adjust the steering head bearing.
. INSPECTION/ADJUSTMENT VENOX DRIVE CHAIN Check the drive chain slack. Specified Slack: 10～20mm Drive Chain Adjustment: Rear Axle Nut 1. First loosen the rear axle nut. 2. Adjust the right and left chain adjusting nuts to align the right and left index marks with the punch marks on the chain adjusters.
. INSPECTION/ADJUSTMENT VENOX IGNITION TIMING The CDI ignition timing is not adjustable, a kind of fully transistor ignition. If the timing is incorrect, check the CDI unit, ignition coil and A.C. generator and replace any faulty parts. Remove the ignition timing eye hole cap on the left crankcase cover.
. INSPECTION/ADJUSTMENT VENOX Lock Nut Adjusting Nut When minor adjustment is required, adjust by turning the adjusting nut on the throttle cable. Choke Rod Check the choke rod operating properly if smoothly or not. Choke Rod Valve Remove the choke rod valve. Check the choke rod valve for wear, fouling and carbon deposits.
. INSPECTION/ADJUSTMENT VENOX If the oil level is low, add the recommended oil to the proper level. Recommended Oil: SAE 5W-50 API:SF When changing engine oil, be sure to tighten Drain Bolt the drain bolt securely. Check the drain bolt washer for damage. Oil Capacity: Full capacity : 2.5 liter At change with oil filter : 2.2 liter At change without oil filter : 2.0 liter...
. INSPECTION/ADJUSTMENT VENOX Upper Limit COOLING SYSTEM Place the motorcycle on its main stand on level ground for coolant level check. Check if the coolant level is between the upper and lower limits on the reserve tank. If the coolant level is too low, it means that there are abnormal conditions.
. INSPECTION/ADJUSTMENT VENOX Screws AIR CLEANER AIR CLEANER REPLACEMENT Remove the right side cover. Remove the air cleaner case cover screws and the cover. Remove the air cleaner element. Check the element and replace it with a new one if it is excessively dirty or damaged. CHANGE INTERVAL Air Cleaner More frequent replacement is required if...
. INSPECTION/ADJUSTMENT VENOX Bolts VALVE CLEARANCE Inspect and adjust valve clearance while the engine is cold (below 35 ). Remove the four cylinder head cover bolts and the cylinder head cover. Front cylinder: Rotate the generator flywheel to bring the camshaft to the top dead center on the compression stroke and align the “T1”...
. INSPECTION/ADJUSTMENT VENOX 9.Adjust the CO density of the front/rear carburetor at 3.0±0.5% by turning the pilot screw. 10.Slightly turn the throttle grip for several time again and recheck if the idle speed, vacuum value and CO density is within the specified range.
. LUBRICATION SYSTEM VENOX LUBRICATION SYSTEM...
. LUBRICATION SYSTEM VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • The service and maintenance of this section can be accomplished with the engine installed in the frame. • Use care when removing and installing the oil pump not to allow dust and foreign matters to enter the engine and oil line.
. LUBRICATION SYSTEM VENOX Upper Limit ENGINE OIL/OIL FILTER OIL LEVEL • Place the motorcycle upright on level ground for engine oil level check. • Run the engine for 2～3 minutes and check the oil level after the engine is stopped for 2～3 minutes.
. LUBRICATION SYSTEM VENOX Clutch Cable OIL PUMP REMOVAL 1. Disconnect the clutch cable. 2. Remove the right crankcase cover bolts and right crankcase cover. When installing, make sure to use a new right crankcase cover gasket. Right Crankcase Cover Bolts Remove the bolt attaching the starter gear.
. LUBRICATION SYSTEM VENOX Bolts DISASSEMBLY Remove the three oil pump mounting bolts and the oil pump body. Outer Rotor Feeler Gauge INSPECTION Measure the pump body-to-outer rotor clearance. Service Limit: 0.20mm Pump Body Outer Rotor Feeler Gauge Measure the inner rotor-to-outer rotor clearance.
. LUBRICATION SYSTEM VENOX Outer Rotor Pump Shaft ASSEMBLY Install the outer rotor and inner rotor into the pump body. Insert the pump shaft. Insert the pump shaft by aligning the flat on the shaft with the flat in the inner rotor.
. FUEL SYSTEM VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS Gasoline is very dangerous. When working with gasoline, keep sparks and flames away from the working area. Gasoline is extremely flammable and is explosive under certain conditions. Be sure to work in a well-ventilated area. •...
. FUEL SYSTEM VENOX TROUBLESHOOTING Engine cranks but won’t start Engine lacks power • No fuel in tank • Clogged air cleaner • No fuel to carburetor • Faulty carburetor • Cylinder flooded with fuel • Faulty ignition system • No spark at plug •...
. FUEL SYSTEM VENOX Screw CARBURETOR REMOVAL Remove the seat and fuel tank. Loosen the air cleaner connecting tube band screw. Bolt Remove the five lock bolts. Remove the carburetor cap. Air Cleaner Adjusting Nut Lock Nut Loosen the throttle cable adjusting nut and lock nut, and disconnect the throttle cable from the carburetor.
. FUEL SYSTEM VENOX Screw VACUUM CHAMBER DISASSEMBLY Remove the four vacuum chamber cover screws and the cover. Vacuum Chamber Cover Spring Remove the spring , vacuum diaphragm and piston. Vacuum Diaphragm Remove the needle holder and jet needle. Be careful not to damage the vacuum diaphragm.
. FUEL SYSTEM VENOX ASSEMBLY Install the vacuum piston/diaphragm in the carburetor body. Install the spring and then install the vacuum chamber cover. Tighten the four screws. • Be careful not to damage the diaphragm. • Hold the vacuum piston while tightening the vacuum chamber cover.
. FUEL SYSTEM VENOX Slow Jet Pilot Screw Needle Jet Remove the main jet, needle jet holder, needle jet, slow jet and pilot screw. • Be careful not to damage the fuel jets and pilot screw. • Before removing, turn the pilot screw in and carefully count the number of turns until it seats lightly and then make a note of this.
. FUEL SYSTEM VENOX Float Install the float valve, float and float pin. Secure the float pin with the screw. Float Pin Screw FLOAT LEVEL INSPECTION Float Level Gauge • Check the operation of the float valve and float before this inspection. •...
. FUEL SYSTEM VENOX INSTALLATION Install the fuel tank in the reverse order of removal. AIR CLEANER Bolt Loosen the air cleaner connecting tube band screw. Disconnect the transmission case breather tube from the air cleaner. Remove the bolt and air cleaner case. The installation sequence is the reverse of removal.
. ENGINE REMOVAL/INSTALLATION VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • A engine stand or floor jack is required to support and maneuver the engine. • The following parts can be serviced with the engine installed in the frame: ⎯ Cylinder head/valves (Section 6) ⎯...
5. ENGINE REMOVAL/INSTALLATION VENOX Fuel Tank ENGINE REMOVAL Remove the seat and fuel tank. Remove the left and right side cover. Disconnect the fuel tube from the auto fuel valve. Disconnect the speedometer wire coupler from the hardness wire. Generator Wire Coupler Disconnect the A.C.
. ENGINE REMOVAL/INSTALLATION VENOX Remove the exhaust muffler brace lock bolt. Torgue: 3.0~3.6kg-m Bolt Bolt Remove the exhaust muffler hanger lock bolt. Remove the exhaust muffler. Torgue: 3.0~3.6kg-m Clutch Cable Disconnect the clutch cable. Remove the coolant hose. Hose...
5. ENGINE REMOVAL/INSTALLATION VENOX Left Rear Remove the gear shift pedal attaching bolt Crankcase Cover and the gear shift pedal. Remove the three left rear crankcase cover attaching bolts and the cover. Gear Shift Pedal Drive Chain Remove the drive gear attaching bolt. Remove the drive gear and drive chain.
. ENGINE REMOVAL/INSTALLATION VENOX Lower Bracket Nut Remove the lower bracket bolt and nut. Tilt the engine to dismount the engine from right side. Torgue: 3.5~4.5kg-m ENGINE INSTALLATION Install the engine in the reverse order of removal. Install the engine to its original position with a jack or other adjustable support.
. CYLINDER HEAD/VALVES VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • When assembling, apply engine oil to the valve guide movable parts, valve arm and camshaft sliding surfaces for initial lubrication. • The valve rocker arm is lubricated with engine oil through the cylinder head engine oil passages. Clean and unclog the oil passages before cylinder head assembly.
6. CYLINDER HEAD/VALVES VENOX TROUBLESHOOTING • The poor cylinder head operation can be diagnosed by a compression test or by tracing engine top-end noises. Poor performance at idle speed White smoke from exhaust muffler • Compression too low • Worn or broken valve stem or valve guide •...
6. CYLINDER HEAD/VALVES VENOX Bolts CYLINDER HEAD COVER REMOVAL Remove the eight cylinder head cover bolts for twin cylinder cover. Remove the cylinder head cover. Inspect the cylinder head cover O-ring for damage or deterioration and replace if necessary. Torgue: 0.8~1.2kg-m Remove the cam chain tensioner cap screw and the O-ring.
. CYLINDER HEAD/VALVES VENOX Dowel Pins Remove the camshaft holder and dowel pins. Remove the camshaft gear from the cam Cam Chain chain and remove the camshaft. Suspend the cam chain with a piece of wire to keep it from falling into the crankcase.
6. CYLINDER HEAD/VALVES VENOX Bolt CYLINDER HEAD REMOVAL Remove the cylinder head bolt. Remove the cylinder head. ROCKER ARMS DISASSEMBLY Rocker Arm Remove the rocker arm shafts. Remove the rocker arm. Rocker Arm Shafts Washer Check the rocker arm shafts washer and O- ring for damage or deformation and replace with a new one if necessary.
. CYLINDER HEAD/VALVES VENOX Measure the diameter of this column. Service Limits: 9.94mm replace if below CYLINDER HEAD DISASSEMBLY Remove the valve spring cotters, retainers, springs, spring seats, washers and valve stem seals with a valve spring compressor. • Be sure to compress the valve springs with a valve spring compressor.
6. CYLINDER HEAD/VALVES VENOX VALVE /VALVE GUIDE Inspect each valve for bending, burning, scratches or abnormal stem wear. Check valve movement in the guide. Measure each valve stem O.D. Service Limits: 4.90mm replace if below 4.90mm replace if below Measure each valve guide I.D. Valve Guide Service Limits: IN: 5.05mm replace if over EX: 5.05mm replace if over...
. CYLINDER HEAD/VALVES VENOX Plastic Hammer Tap the valve stems gently with a plastic hammer for 2～3 times to firmly seat the cotters. Be careful not to damage the valves. ROCKER ARMS INSTALLATION Install the rocker arm shafts bolt and the rocker arm.
• Both of crankcase need to be replaced if anyone crankcase is damaged. • After disassembly, clean the removed parts and dry them with compressed air before inspection. SPECIFICATIONS Standard (mm) Service Limit (mm) Item VENOX 250 VENOX 250 I.D. 58.0～58.015 58.30 ⎯...
. CRANKSHAFT/PISTON/CYLINDER VENOX Bolts CRANKCASE REMOVAL The following parts must be removed before removing the crankcase: • Cylinder head /camshaft. • Starter motor/generator/left and right crankcase cover/clutch. • Clutch/gear shift mechanism. Remove the six attaching bolts on the upper crankcase. Bolts Remove the eleven attaching bolts on the lower crankcase.
. CRANKSHAFT/PISTON/CYLINDER VENOX Nuts CRANKSHAFT REMOVAL Remove the four attaching nut on the connecting rod cap. Remove the connecting rod cap. Torgue: 2.4kg-m Crankshaft Remove the crankshaft. INSPECTION Measure the crankshaft runout. Service Limit: 0.1mm replace if over...
. CRANKSHAFT/PISTON/CYLINDER VENOX Piston/Connecting Rod PISTON REMOVAL Remove the piston/connecting rod. Piston Piston Pin Remove the piston pin clip. Take out the piston pin. Clip INSPECTION Inspect the piston, piston pin and piston rings. Remove the piston rings. Take care not to damage or break the piston rings during removal.
. CRANKSHAFT/PISTON/CYLINDER VENOX Insert each piston ring into the cylinder bottom. Use the piston head to push each piston ring into the cylinder. Measure the piston ring end gap. Service Limit: 0.50mm Measure the piston pin hole I.D. Service Limit: 16.012mm replace if over Measure the piston pin O.D.
. CRANKSHAFT/PISTON/CYLINDER VENOX CYLINDER INSPECTION Inspect the cylinder bore for wear, scratches or damage. Measure the cylinder I.D. at three levels of top, middle and bottom at 90° to the piston pin (in both X and Y directions). Service Limit: 58.30mm replace if over Measure the cylinder-to-piston clearance and take the maximum figure measured.
. CRANKSHAFT/PISTON/CYLINDER VENOX Crank Pin Mark There is a mark on the connecting rod big end. Connecting Rod Crank Pin Bearing Big End Mark Mark Chose(Color) A(Brown) B(Green) B(Green) C(Yellow) First install the plate bearings before the connecting rod big end is installed. Press the flange on the plate bearing into the connecting rod groove.
. CRANKSHAFT/PISTON/CYLINDER VENOX A.C.G. Side Mark CRANK BEARING CHOICE Crankcase Crank Pin Bearing Mark Mark Chose(Color) A(Brown) B(Green) B(Green) C(Yellow) One-Way Side Mark Flange First install the plate bearings before installing the upper and lower crankcase. Apply engine oil to the plate bearing on the crankcase.
. CRANKSHAFT/PISTON/CYLINDER VENOX Piston INSTALLATION Install other removed parts in the reverse of order of removal. 7-10...
8. GENERATOR/LEFT CRANK CASE COVER VENOX 7.5~8.5kg-m 0.8~1.2kg-m...
8. GENERATOR/LEFT CRANK CASE COVER VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • The starter motor, generator, left crankcase cover and starter clutch can be serviced in the frame. • Do not install the starter clutch forcedly. • Install the generator by aligning the groove in the flywheel with the key on the crankshaft. TORQUE VALUE Flywheel nut: 7.5～8.5kg-m SPECIAL TOOLS...
8. GENERATOR/LEFT CRANK CASE COVER VENOX Generator Wire Coupler LEFT CRANKCASE COVER/ GENERATOR REMOVAL Remove the seat and fuel tank. Remove the left and right side cover. Disconnect the fuel tube from the auto fuel valve. Disconnect the A.C. generator and starter motor wire coupler.
8. GENERATOR/LEFT CRANK CASE COVER VENOX Flywheel Puller Install the flywheel puller. Flywheel Remove the flywheel using a flywheel puller. GENERATOR INSTALLATION Groove Install the generator flywheel. Hold the flywheel with a flywheel holder and tighten the flywheel lock bolt. •...
. CLUTCH/GEAR SHIFT MECHANISM VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • The clutch and gear shift mechanism can be serviced in the frame. • Install the clutch plates in the same chamfer direction. • Install the thrust washer with the chamfer facing up and the flat facing down. SPECIFICATIONS Item Standard (mm)
. CLUTCH/GEAR SHIFT MECHANISM VENOX TROUBLESHOOTING Clutch slips during acceleration Clutch won’t operate and motorcycle • No free play moves slowly • Worn friction disk • Excessive free play • Weak spring • Bent clutch plate Clutch won’t operate Too much pressure on clutch lever •...
. CLUTCH/GEAR SHIFT MECHANISM VENOX Right Crankcase Cover RIGHT CRANKCASE COVER REMOVAL Drain the engine oil. Disconnect the clutch cable. Remove the right crankcase cover attaching bolts and right crankcase cover. Bolts Remove the right crankcase cover. Bolt ONE-WAY CLUTCH REMOVAL Remove the one-way clutch mounting bolt and one-way clutch.
. CLUTCH/GEAR SHIFT MECHANISM VENOX Measure the starter gear shaft O.D. and I.D. Service Limit: O.D. 42.0mm replace if over. I.D. 32.20mm replace if below. One-Way Clutch Remove the one-way clutch rollers, plungers and springs. Bearing Check the one-way clutch bearing for smooth turning.
. CLUTCH/GEAR SHIFT MECHANISM VENOX INSTALLATION Install the one-way clutch and starter reduction gear in the reverse order of removal. Align the flange of the one-way clutch with the crank mark. CLUTCH REMOVAL Clutch Lifter Tension Springs Remove the four clutch lifter bolts. Remove the clutch lifter and four tension springs.
. CLUTCH/GEAR SHIFT MECHANISM VENOX Clutch Center Remove the clutch center, clutch friction disks and plates. Remove the washer, clutch outer. Washer Clutch Outer INSPECTION CLUTCH TENSION SPRING Measure each clutch tension spring free length. Service Limit: 31.0mm replace if below CLUTCH FRICTION DISK Clutch Friction Disk Measure each clutch friction disk thickness.
. CLUTCH/GEAR SHIFT MECHANISM VENOX CLUTCH PLATE Measure each clutch plate bending using a feeler gauge. Service Limit: 0.10mm replace if over Feeler Gauge Clutch Plate Clutch Outer CLUTCH OUTER Inspect the clutch outer groove for scratches caused by the friction disks. Measure the clutch outer I.D.
.TRANSMISSION SYSTEM VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • During crankcase separation, do not separate the crankcase halves with an iron hammer to avoid crankcase deformation or damage. • After separation, be careful not to damage the right and left crankcase mating surfaces to avoid oil leakage.
.TRANSMISSION SYSTEM VENOX Bolts GEAR SHIFT MECHANISM REMOVE Remove the gear shift pedal. Remove the two water pump attaching bolts and remove the water pump. Water Pump Remove the three gear shift mechanism Bolts cover attaching bolts. Remove the gear shift mechanism cover. Cover Remove the gear shift spindle.
.TRANSMISSION SYSTEM VENOX Gear Shift Cam Remove the stopper and spring attaching bolts. Remove the gear shift cam bolt. Remove the gear shift cam and set pin. Stopper Spring GEAR/SHAFT COLLAR INSPECTION Ball Bearing Holder Drum Stopper Spring Check the drum stopper and spring for damage, or change shape.
.TRANSMISSION SYSTEM VENOX Bolts Remove the eleven lower crankcase attaching bolts. Separate the upper and lower crankcase halves. Slightly tap the crankcase to separate the crankcase halves using a plastic hammer. Clip Remove the main/counter shaft ball bearing clip. Be careful not to lose the ball bearing clip.
.TRANSMISSION SYSTEM VENOX Transmission Fork Remove the transmission fork shaft and transmission forks. Remove the transmission drum. Transmission Drum INSPECTION TRANSMISSION FORK/DRUM Inspect each transmission fork for bending or damage. Measure each transmission fork claw thickness. Service Limit: 5.0mm replace if below Measure each transmission fork shaft hole I.D.
.TRANSMISSION SYSTEM VENOX Left Center Right INSTALLATION The installation sequence is the reverse of removal. Transmission fork make is as follows R(right),C(center),L(left). Main Shaft TRANSMISSION GEARS REMOVAL Remove the transmission main shaft and counter shaft from the upper crankcase. When removing, the transmission gears must be removed as a set.
.TRANSMISSION SYSTEM VENOX Measure each shaft collar I.D./O.D. Service Limits: Main shaft 4th gear collar I.D.22.081mm replace if over Main shaft 4th gear collar O.D.24.919mm replace if below Main shaft 5th gear collar O.D.24.927mm replace if below Countershaft 1st gear collar I.D.20.081mm replace if over Countershaft 1st gear collar O.D.22.919mm replace if below...
.TRANSMISSION SYSTEM VENOX BEARING REPLACEMENT Remove the main shaft and countershaft bearings from the main shaft and countershaft using a bearing remover. Special Bearing Remover Bearing Remover Drive the new bearing into the shaft using a bearing driver. • The flange of the oil seal should fix in the groove of the upper crankcase.
.TRANSMISSION SYSTEM VENOX INSTALLATION The installation sequence is the reverse of removal. 10-11...
. COOLING SYSTEM VENOX SCHEMATIC DRAWING 0.8~1.2kg-m 11-0...
. COOLING SYSTEM VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • The engine must be cool before servicing the cooling system. When the coolant temperature is over 100 , never remove the radiator cap to release the pressure because the boiling coolant may cause danger. •...
. COOLING SYSTEM VENOX Radiator Tester COOLING SYSTEM TESTING RADIATOR CAP INSPECTION Install the radiator cap onto the radiator tester and apply specified pressure to it. It must hold specified pressure for at least six seconds. Apply water to the cap sealing surface before testing.
. COOLING SYSTEM VENOX Loosen the hose band and disconnect the upper hose from the radiator. Upper Hose Disconnect the thermostatic switch wire Fan Motor Wire Coupler coupler. Disconnect the fan motor wire coupler. Thermostatic Switch Wire Coupler Remove the two bolts on the radiator. Bolts Bolts RADIATOR DISASSEMBLY...
. COOLING SYSTEM VENOX FAN MOTOR INSPECTMENT Check fan motor by battery. THERMOSTATIC SWITCH INSPECTMENT When coolant temperature lower then 90±2 the thermostatic switch OFF. When coolant temperature over 90±2 thermostatic switch ON. RADIATOR INSTALLATION The installation sequence is the reverse of removal.
. COOLING SYSTEM VENOX WATER PUMP MECHANICAL SEAL (WATER SEAL) INSPECTION Inspect the telltale hole for signs of mechanical seal coolant leakage. If the mechanical seal is leaking, remove the water pump. Water Pump Telltale Hole Outlet Cupreous Iron Pipe WATER PUMP REMOVAL Remove the coolant inlet hose and outlet cupreous iron pipe.
. COOLING SYSTEM VENOX Thermosensor THERMOSENSOR THERMOSENSOR REMOVAL Remove the seat, fuel tank and left/right side cover. Drain the coolant. Disconnect the thermosensor wire. Remove the thermosensor. Thermosensor Wire Thermosensor THERMOSENSOR INSPECTION Suspend the thermosensor in a pan of water over a burner and measure the resistance through the sensor as the water heats up.
. COOLING SYSTEM VENOX Bolts Remove the two bolts and separate the thermostat housing halves. Torgue: 0.8~1.2 kg-m Thermostat Thermostat Remove the thermostat from the thermostat housing. THERMOSTAT INSPECTION Thermostat Suspend the thermostat in a pan of water over a burner and gradually raise the water temperature to check its operation.
. COOLING SYSTEM VENOX THERMOSTAT INSTALLATION The installation sequence is the reverse of removal. Replace the O-ring with a new one and apply sealant to it. Fill the radiator system with the specified coolant. Thermostat Housing 11-10...
. FRONT WHEEL/SUSPENSION/STEERING VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS SPECIFICATIONS Item Standard (mm) Service Limit (mm) ⎯ Front axle shaft runout ⎯ Axial Front wheel rim runout ⎯ Radial ⎯ Front fork spring free length 334.5 ⎯ Front fork tube runout ⎯...
. FRONT WHEEL/SUSPENSION/STEERING VENOX TROUBLESHOOTING Hard steering • Insufficient tire pressure • Excessively tightened steering stem nut • Damaged steering stem bearings • Damaged steering stem bearing races Steers to one side or does not track straight • Uneven front shock absorbers •...
. FRONT WHEEL/SUSPENSION/STEERING VENOX Throttle Housing HANDLEBAR REMOVAL Remove two screws attaching the throttle housing and the throttle housing. Screws Master Cylinder Throttle Pipe Disconnect the throttle cable from the throttle grip and then remove the throttle pipe from the handlebar. Throttle Cable Bolts Remove the two master cylinder holder...
. FRONT WHEEL/SUSPENSION/STEERING VENOX Upper Fork Bridge Remove the four upper fork bridge bolts to remove the handlebar. Bolts INSTALLATION Place the handlebar on the upper fork bridge seat. Install the upper fork bridge set plates onto the handlebar. First tighten the front bolts and then the rear bolts.
. FRONT WHEEL/SUSPENSION/STEERING VENOX THROTTLE PIPE INSTALLATION Clean the handlebar surface and install the throttle pipe. Check the throttle grip for proper operation. Connect the throttle cable to the throttle grip. Apply grease to the throttle cable. Install the throttle housing by aligning the pin on the housing with the punch hole in the handlebar.
. FRONT WHEEL/SUSPENSION/STEERING VENOX INSPECTION Set the axle in V blocks and measure the runout. Service Limit: 0.2mm replace if over WHEEL RIM INSPECTION Place the front wheel in a turning stand. Spin the wheel by hand and measure the rim runout by using a dial gauge.
. FRONT WHEEL/SUSPENSION/STEERING VENOX Axle Collar Remove the axle collar and dust seal from the right side of the wheel. Remove the dust seal. Bolts Remove the six bolts and the brake disk. Dust Seal Bearing Remover Drive out the wheel bearings and distance collar.
. FRONT WHEEL/SUSPENSION/STEERING VENOX Dust Seal Install the brake disk and tighten the six bolts. Apply grease to the dust seal and install it. Brake Disk Groove Install the speedometer gearbox by aligning the tabs with the grooves. Flange Tab Speedometer Gearbox Apply grease to the speedometer gearbox and dust seal, then install them to the wheel...
. FRONT WHEEL/SUSPENSION/STEERING VENOX Groove INSTALLATION Install the front wheel onto the front fork, aligning the tab on the front fork with the groove in the speedometer gearbox. Speedometer Cable Insert the axle shaft and tighten the axle nut. Torque: 6.0～8.0kg-m Connect the speedometer cable and secure it with the screw.
. FRONT WHEEL/SUSPENSION/STEERING VENOX Brake Caliper Bolts Remove the two bolts attaching the brake caliper holder. Remove the two headlight holder screws. Signal Light Holder Upper Fork Bridge Mount Bolt Remove the upper fork bridge mount bolt. Screw Remove the turn signal light holder screw. Remove the lower fork bridge mount bolt and then remove the right and left front forks.
. FRONT WHEEL/SUSPENSION/STEERING VENOX BOTTOM CONE RACE REPLACEMENT Drive out the bottom cone race. Drive in a new bottom cone race onto the steering stem. Bottom Cone Race Top Cone Race STEERING STEM INSTALLATION Apply grease to the top and bottom ball races and steel balls.
. REAR WHEEL/BRAKE/SUSPENSION VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • When installing the drive chain joint clip, the cutout of the clip should be opposite to the rotating direction. • After the drive chain is adjusted, make sure that the rear brake pedal free play is normal and adjust it if necessary.
. REAR WHEEL/BRAKE/SUSPENSION VENOX Rear Brake Panel REAR WHEEL REMOVAL Remove the rear axle nut. Remove the rear brake adjusting nut. Rear Brake Adjusting Nut Rear Axle Nut Remove the rear brake panel fixing arm bolt. Remove the bushing. Remove the rear brake panel. Loose both of the chain adjuster nut.
. REAR WHEEL/BRAKE/SUSPENSION VENOX Check the wheel bearing play by placing the wheel in a turning stand and spinning the wheel by hand. Axial Radial Check the drive chain gear teeth for wear or damage. Replace the drive chain gear if necessary. Replace Good If the drive chain gear teeth are worn or...
. REAR WHEEL/BRAKE/SUSPENSION VENOX ASSEMBLY Pack all bearing cavities with grease. Drive in the left bearing. Install the distance collar. Drive in the right bearing. • Drive in the bearings squarely. • Install the bearings with the sealed end facing out. Special Bearing driver handle Attachment,37×40mm...
. REAR WHEEL/BRAKE/SUSPENSION VENOX Measure the brake drum I.D. Service Limit: 161.3mm replace if over DISASSEMBLY Brake Remove the springs and brake shoes. Springs Brake Cam Remove the brake arm bolt to remove the brake arm. Remove the dust seal. Remove the brake cam.
. REAR WHEEL/BRAKE/SUSPENSION VENOX Brake Cam Apply grease to the brake cam and anchor pin, then install the brake cam to the brake panel. Apply engine oil to the dust seal and install it to the brake cam. Install the wear indicator plate on the brake cam, aligning the mark on the plate with the groove on the brake cam.
. REAR WHEEL/BRAKE/SUSPENSION VENOX Upper Mount REAR SHOCK ABSORBER REMOVAL/INSTALLATION Remove the shock absorber upper mount nuts and washers and then press down the motorcycle to pull out the shock absorbers. Remove the shock absorber lower mount bolts to remove the rear shock absorbers. INSTALLATION The installation sequence is the reverse of removal.
. REAR WHEEL/BRAKE/SUSPENSION VENOX REAR FENDER REMOVAL Remove the rear carrier. Disconnect the turn signal light, rear stop light and taillight wires. Remove the right and left side cover bolts and then remove the two upper lock bolts to remove the rear fender. When installing, connect and route the taillight and turn signal light wires properly.
. HYDRAULIC BRAKE VENOX SERVICE INFORMATION GENERAL INSTRUCTIONS • Drain the brake fluid from the hydraulic brake system before disassembly. • Do not allow any foreign matters entering the brake reservoir when filling the brake reservoir with brake fluid. • Be careful not to splash brake fluid on any coated surfaces and instrument covers to avoid damage.
. HYDRAULIC BRAKE VENOX TROUBLESHOOTING Loose brake lever • Air in hydraulic brake system • Brake fluid level too low • Hydraulic brake system leakage Tight brake lever • Seized piston • Clogged hydraulic brake system • Smooth or worn brake pad Hard braking •...
. HYDRAULIC BRAKE VENOX Screws BRAKE FLUID CHANGE/AIR BLEED Place the motorcycle on its main stand on level ground and set the handlebar upright. Remove the two screws attaching the brake fluid reservoir cap. Use towel to cover plastic parts and coated surfaces to avoid damage caused by splash of brake fluid.
. HYDRAULIC BRAKE VENOX Bolts BRAKE PAD/DISK BRAKE PAD REPLACEMENT Remove the two bolts attaching the brake caliper holder. The brake pads can be replaced without removing the brake fluid tube. Remove the brake caliper. Remove the brake pad pin bolt and then Brake Caliper remove the pad pin bolt and brake pads.
. HYDRAULIC BRAKE VENOX BRAKE DISK Measure the brake disk thickness. Service Limit: 3.0mm Measure the brake disk runout. Service Limit: 0.3mm BRAKE MASTER CYLINDER REMOVAL Drain the brake fluid from the hydraulic Fluid Tube brake system. Do not splash brake fluid onto any rubber, plastic and coated parts.
. HYDRAULIC BRAKE VENOX INSPECTION Measure the brake master cylinder I.D. Inspect the master cylinder for scratches or cracks. Service Limit: 12.75mm replace if over Measure the brake master cylinder piston O.D. Service Limit: 12.64mm replace if below ASSEMBLY Before assembly, apply brake fluid to all removed parts.
. HYDRAULIC BRAKE VENOX Place the brake master cylinder on the handlebar and install the master cylinder holder with the “UP” mark facing up, aligning the tab on the holder with the hole in the handlebar. First tighten the upper bolt and then tighten the lower bolt.
. HYDRAULIC BRAKE VENOX Compressed Air Remove the pistons from the brake caliper. Use compressed air to press out the pistons through the brake fluid inlet opening and place a towel under the caliper to avoid contamination caused by the removed pistons.
. HYDRAULIC BRAKE VENOX ASSEMBLY Clean all removed parts. Apply silicon grease to the pistons and oil seals. Lubricate the brake caliper cylinder inside wall with brake fluid. Install the oil seals and then install the brake caliper pistons with the grooved side facing out.
. IGNITION SYSTEM SERVICE INFORMATION GENERAL INSTRUCTIONS • Inspect the ignition system according to the sequence specified in the Troubleshooting 15-3. • The ignition system has a CPU in the CDI unit, so the ignition timing is not adjustable. • Do not drop or impact the CDI unit with strong force to avoid damage. Be careful when removing it.
. IGNITION SYSTEM TROUBLESHOOTING Engine stalls immediately after it starts • Weak spark • Improper ignition timing • Faulty CDI unit No spark at plug • Faulty ignition switch • Poorly connected, broken or shorted wire −Between pulser coil, CDI unit and ignition coil −Between exciter coil and CDI unit −Between CDI unit and ignition coil −Between CDI unit and ignition switch...
. IGNITION SYSTEM Ignition Coil IGNITION COIL CONTINUITY TEST Disconnect the ignition coil primary wire coupler and measure the resistance between the ignition coil primary wire terminals. Resistance: 3.57Ω~4.83Ω Spark Plug Cap Measure the secondary coil resistance between the spark plug wire and the primary coil terminal.
. IGNITION SYSTEM CDI UNIT CDI Unit INSPECTION Disconnect the CDI unit coupler. Check for continuity with the coupler on the hardness wire side and CDI unit. Inspection table is as follows. The CDI unit is fully transistorized. For accurate testing, it is necessary to use a specified tester.
. IGNITION SYSTEM PULSER COIL INSPECTION Disconnect the pulser coil wire coupler and measure the resistance between the blue/ yellow and green/white wire terminals. Resistance: 396～594Ω Picture C Picture D 15-6...
• When inspecting the A.C. generator, use an electric tester. • Route the charging system wires properly to avoid short-current due to wires being twisted or kinked. SPECIFICATIONS VENOX 250 Battery capacity 12V8AH Battery Electrolyte specific gravity 1.32...
. CHARGING SYSTEM BATTERY REMOVAL Remove the seat. Remove the left side cover. First disconnect the battery negative cable and then the positive cable. Remove the two battery set plate lock nuts. BATTERY CHARGING Connect the charger positive cable to the battery positive cable.
. CHARGING SYSTEM LIMIT VOLTAGE TEST: Start the engine and gradually increase the engine speed to measure the limit voltage. Limit Voltage: 14.5±0.5V/5000rpm Note: Test when the battery is fully charged. When testing the limit voltage, also use a tachometer for operation. A.C.
. CHARGING SYSTEM INSPECTION Remove the regulator/rectifier wire coupler. Normal Red/White Direction Check the continuity between the wire terminals. Normal Direction: Continuity (+) Probe (-) Probe Yellow Green Red/White Yellow Reverse Direction Green Reverse Direction: No Continuity (+) Probe (-) Probe Green Yellow Yellow...
. STARTING SYSTEM SERVICE INFORMATION GENERAL INSTRUCTIONS • The removal of starter motor can be accomplished with the engine installed in the frame. • When connecting the starting system wires, connect them securely to avoid hard starting due to poor connection. TROUBLESHOOTING Starter motor won’t turn Lack of power...
. STARTING SYSTEM STARTER MOTOR REMOVAL Remove the two starter motor mounting bolts and the motor. Before removing the starter motor, turn the ignition switch OFF and remove the battery ground. Then, turn the ignition switch on to check if the starter motor operates properly.
. STARTING SYSTEM STARTER RELAY INSPECTION Turn the ignition switch ON and the starter relay is normal if you hear a “click” when the starter button is depressed. If there is no click sound: • Inspect the starter relay voltage •...
. LIGHTS/INSTRUMENT/SWITCHES/HORN SERVICE INFORMATION GENERAL INSTRUCTIONS • All plastic plugs have locking tabs that must be released before disconnecting. • An electric tester must be used for checking the continuity between two points. The electric tester also contains a voltmeter which can be used to measure voltage. •...
. LIGHTS/INSTRUMENT/SWITCHES/HORN HEADLIGHT REMOVAL Remove the left sides of attaching bolts and screws on headlight fairing to dismantle the fairing. Remove the headlight unit and disconnect the headlight wire coupler. Screws Bulb Bulb Socket Remove the headlight bulb and bulb socket. Check the bulb for damage and replace with a new one if necessary.
. LIGHTS/INSTRUMENT/SWITCHES/HORN Bulb TURN SIGNAL LIGHT Remove the turn signal light shell and the bulb. Check the bulb for damage and replace with a new one if necessary. The installation sequence is the reverse of removal. STOP LIGHT/TAIL LIGHT Remove the two taillight shell screws and the shell.
. LIGHTS/INSTRUMENT/SWITCHES/HORN INSPECTION Check for continuity between the wires indicated below. Color Black Red/White Position STARTER BUTTON Disconnect the right switch wire coupler. Check for continuity between the black/white and yellow/red wires. Color Black/White Yellow/Red Position FREE PUSH Starter Switch Coupler HORN BUTTON Disconnect the left switch wire coupler.
. LIGHTS/INSTRUMENT/SWITCHES/HORN HORN The horn is normal if it sounds when a 12V battery is connected across the horn wire terminals. Replace the horn if it does not sound. Horn FUEL GAUGE Disconnect the fuel gauge and fuel unit wire couplers. Connect the fuel gauge green wire with the yellow/white wire.
. LIGHTS/INSTRUMENT/SWITCHES/HORN REAR STOP SWITCH Remove the right side cover. Disconnect the rear stop switch wire coupler. Check for continuity between the rear stop switch wires. Brake pedal depressed: Continuity. Brake pedal released: No continuity. Rear Brake TURN SIGNAL SWITCH Switch Turn Signal Coupler...
. LIGHTS/INSTRUMENT/SWITCHES/HORN ENGINE STOP SWITCH Disconnect the engine stop switch wire coupler. Check for continuity between the engine stop switch wires. Color Black/White Black/Green Position Switch Engine Stop Coupler DIMMER SWITCH Disconnect the dimmer switch wire coupler. Check for continuity between the dimmer switch wires.
. LIGHTS/INSTRUMENT/SWITCHES/HORN INSPECTION Check the fuel unit O-ring for wear, damage or deformation. Replace if necessary. Measure the continuity between the fuel unit wire terminals with the float at the upper (Full) and lower (Empty) positions. Resistances: Upper (Full): No continuity Lower (Empty): Continuity Connect the fuel unit wire coupler to the wire harness and turn the ignition switch...
. LIGHTS/INSTRUMENT/SWITCHES/HORN THROTTLE POSITION SENSOR Disconnect the throttle position sensor wire coupler on carburetor. Check for the resistance among three wires of the throttle position sensor. Unit:KΩ 0~5±1 0~5±1 Throttle Position Sensor SIDE STAND SWITCH Disconnect the side stand switch wire Side Stand Switch Wire Coupler coupler.