Do you have a question about the GN125F and is the answer not in the manual?
Questions and answers
Leo
February 15, 2025
Because in the oil change specifications it says oil capacity 850.filter change 950.overhaul.1300.Could you explain this to me?
3 comments:
Mr. Anderson
February 15, 2025
The oil capacity for a Suzuki GN125F is as follows: - Oil change: 850ml - Filter change: 950ml - Overhaul: 1300ml
This answer is automatically generated
Leodany
February 16, 2025
@Mr. Anderson
Leodany
February 16, 2025
@Mr. Anderson . Pero porque dice 3 medidas de aceite diferentes.puedes explicarme bien eso.es decir que a medida que va realizando el cambio de aceite ahí que aumentarle más
Helene
April 17, 2025
Numéro pieces phare avant gn125f
Leodany
April 20, 2025
Hello .At what RPM should the Suzuki 125 work in neutral? Because I don't see that part in the manual.
Porfirio Mendoza
January 20, 2025
Dónde está el tornillo de ajuste del carburador GN125F
They may not represent the actual motorcycle exactly in detail. This manual is written for persons who have enough knowledge, skills and tools, including special tools, for servicing SUZUKI motorcycles. If you do not ELECTRICAL have the proper knowledge and tools, ask your authorized SUZUKI motorcycle dealer to help you.
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HOW TO USE THIS MANUAL TO LOCATE WHAT YOU ARE LOOKING FOR: 1.The text of this manual is divided into 7 sections. 2.The section titles are listed in the GROUP INDEX. 3.Holding the manual as shown as at the right will allow you to find the first page of the section easily.
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SYMBOL The following symbols are instructions and necessary information for maintenance. SYMBOL SYMBOL DEFINITION DEFINITION Torque control required. Apply THREAD LOCK “1360" Data beside it indicates specified 99000-32130 torque. Apply oil. Use engine oil unless Apply or use the absorber oil otherwise specified.
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WIRE COLOR ........Grown Black ........Light blue Violet Blue ........Light green White Brown ........Orange Yellow Deep green ......Pink Green Black with Blue tracer Orange with Blue tracer .....
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GENERAL INFORMATION CONTENTS WARNING/CAUTION/NOTE GENERAL PRECAUTIONS SERIAL NUMBER LOCATION FUEL AND OIL RECOMMENDATION BREAK-IN PROCEDURE SPECIFICATIONS...
GENERAL INFORMATION WARNING/CAUTION/NOTE Please read this manual and follow its instructions carefully. To emphasize special information, the symbol and the words WARNING,CAUTION and NOTE have special meanings. Pay special attention to the messages highlighted by these signal words. WARNING Indicates a potential hazard that could result in death or injury. Indicates a potential hazard that could result in motorcycle damage.
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GENERAL INFORMATION If parts replacement is necessary, replace the parts with SUZUKI GENUINE PARTS or their equivalent. When removing parts that are to be reused, keep them arranged in an orderly manner so that they may be reinstalled in the proper order and orientation.
GENERAL INFORMATION SPECIFICATIONS DIMENSIONS AND CURB WEIGHT Overall length 2 000 mm Overall width 815 mm Overall height 1 100 mm Wheelbase 1 300 mm Ground clearance 175 mm Curb weight 113 kg ENGINE Single cylinder, vertical, air-cooled, four stroke Type Number of cylinders Bore...
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GENERAL INFORMATION ELECTRIC Ignition type Ignition timing 13° B.T.D.C below 2 000 r/min Spark plug NGK CR8E Battery 12V 7Ah Fuse 15 A Headlight 12V, 35W/35W Tail light/brake light 12V, 5W/21W Turn signal light 12V, 10W Position light 12V, 5W CHASSIS Front absorber Telescopic...
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PERIODIC MAINTENANCE CONTENTS PERIODIC MAINTENANCE MAINTENANCE PROCEDURES BATTERY/FUSE AIR FILTER MUFFLER NUT AND BOLT CYLINDER HEAD, CYLINDER BOLTS AND NUTS VALVE CLEARANCE SPARK PLUG ENGINE OIL ENGINE OIL FILTER OIL SUMP FILTER CLUTCH CABLE PLAY CARBURETOR(IDLING) THROTTLE CABLE PLAY FUEL HOSE FUEL STRAINER DRIVE CHAIN 2-10...
PERIODIC MAINTENANCE PERIODIC MAINTENANCE The chart below lists recommended intervals for all the required periodic service work necessary to keep the motorcycle operating at peak performance and economy. Mileages are expressed in terms of kilometer and time for your convenience. NOTE: More frequent servicing may be performed on motorcycles that are used under severe conditions.
PERIODIC MAINTENANCE MAINTENANCE PROCEDURES This section describes the service procedures for each section of Periodic Maintenance. BATTERY / FUSE Inspect Initial 1 000 km and every 5 000 km BATTERY The battery must be removed to check the electrolyte level and specific gravity.
PERIODIC MAINTENANCE AIR CLEANER Clean every 3 000 km If the air filter is clogged with dust, intake resistance will be increased with a resultant decrease in output and an increase in fuel consumption. Check and clean the element in the following manner. Remove the left frame cover.
PERIODIC MAINTENANCE MUFFLER BOLTS Inspect initial 1 000 km and tighten every 5 000 km Tighten the muffler bolts to the specified torque. CYLINDER HEAD AND CYLINDER NUTS Inspect initial 1 000 km and every 5 000 km. Tighten four M10 nuts to the specified torque when the engine is cold.
PERIODIC MAINTENANCE Hook the valve rocker arm with the special tool, insert the thickness gauge to the valve stem end and the adjusting screw on the rocker arm. 09900 20803 Thickness gauge 11F14-017: Valve adjust spring VALVE CLEARANCE SPECIFICATIONS Valve clearance (when cold) IN.: 0.04-0.07 mm EX.: 0.13-0.18 mm If the clearance is off the specification, bring it into the...
PERIODIC MAINTENANCE ENGINE OIL Change initial 1 000 km and every 3 000 km Engine oil should be changed while the engine is hot. Support the motorcycle by the center stand Drain the engine oil by removing the drain plug and filler cap / gauge.
PERIODIC MAINTENANCE OIL SUMP FILTER Clean every 10 000 km Clean the sump filter to remove any foreign matter that may be collected there. Inspect the screen to insure that it is free of any sign of damage. CLUTCH Inspect initial 1 000 km and every 5 000 km. The clutch play should be 4 mm as measured at the clutch lever holder before the clutch begins to disengage.
PERIODIC MAINTENANCE THROTTLE CABLE PLAY Inspect initial 1 000 km and every 5 000 km To adjust the throttle cable play to be 0.5-1.0 mm. Loosen the locking nut turn the adjuster so that the throttle grip has 0.5 -1.0 mm play. Tighten the locking nut 0.5-1.0m m WARNING...
PERIODIC MAINTENANCE DRIVE CHAIN Clean and lubricate every 1 000 km Clip opening direction DRIVE CHAIN / SPROCKET Visually inspect the drive chain for the below listed possible malconditions. (Lift the rear wheel by placing the center stand, and turn the rear wheel slowly by hand with transmission in NEUTRAL.) 1.
PERIODIC MAINTENANCE BRAKES UPPER Inspect initially at 1 000 km and every 5 000 km. Replace hose every 4 years. Change fluid every 2 years. LOWER FRONT BRAKE(DISC TYPE) Brake fluid level Support the motorcycle body on the center stand, and place the handlebars straight.
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PERIODIC MAINTENANCE AIR BLEEDING THE BRAKE FLUID CIRCUIT Air trapped in the fluid circuit acts like a cushion to absorb a large proportion of the pressure developed by the master cylinder and thus interferes with the full braking performance of the caliper brake. The presence of air is indicated by "sponginess"...
PERIODIC MAINTENANCE REAR BRAKE Rear brake pedal height Adjust the brake pedal limit screw to set the brake pedal at the position of 10-20mm higher than the footrest, then tighten the locking nut. Rear brake pedal height : 10-20 mm Rear brake pedal travel Rear brake travel is the distance from stepping on the brake...
PERIODIC MAINTENANCE TIRES Inspect initial 1 000 km and every 5 000 km Check the tire pressure and surface during the maintenance. There are serial marks T.W.I. (Tire Wear Indicator) in the edge of the tire. Check the block of T.W.I. in the tread near the mark.
PERIODIC MAINTENANCE REAR ABSORBER Press the rear carrier, move the rear absorber up and down four or five times to check for the noise or smooth movement. Inspect the rear absorber spring for damage, deformation or oil leakage. LIGHTING AND SIGNAL Inspect initial 1 000 km and every 5 000 km Inspect the headlight, left and right turn signal light, tail light / brake light and dashboard signal light, replace the light if there...
2-17 COMPRESSION PRESSURE Inspect initial 1 000 km and every 5 000 km Cylinder compression is an indicator of its inner state. The necessity of repair depends on the result of inspection. The record of your authorized maintenance dealer should include compression pressure readings obtained in every maintenance.
2-18 OIL PRESSURE Inspect every 5 000 km Periodically inspect oil pressure of engine so as to ascertain the state of moving parts. Oil pressure inspection procedure Support the motorcycle with the main stand; Install the oil pressure gauge in the position shown in the illustration.
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ENGINE CONTENTS REMOVABLE ENGINE PARTS WITH ENGINE IN PLACE ENGINE REMOVAL AND REMOUNTING CYLINDER HEAD AND VALVE CYLINDER AND PISTON 3-17 CLUTCH 3-21 OIL PUMP 3-25 GEAR SHIFTING SHAFT 3-26 GENERATOR AND STARTING CLUTCH 3-27 CRANKSHAFT, TRANSMISSION AND KICK STARTER DEVICE 3-31...
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ENGINE REMOVING ENGINE PARTS WITH ENGINE IN PLACE UPPER SIDE OF ENGINE Chain tensioner Cylinder head cover Cam shaft Cylinder head Cylinder 3-17 Piston 3-17 RIGHT SIDE OF ENGINE Oil filter 3-21 Clutch cover 3-21 Clutch 3-22 Oil pump 3-25 Gear shifting shaft 3-26 LEFT SIDE OF ENGINE...
ENGINE ENGINE REMOVAL AND INSTALLATION ENGINE REMOVAL Before taking the engine out of the frame, wash the engine with a suitable cleaner. The procedure of engine removal is sequentially explained in the following steps: Support the motorcycle with main stand. Drain the engine oil.
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ENGINE Remove the generator and gear indication light coupler 5 Disconnect the carburetor balancer pipe by unscrewing the clamp screws. Loosen the throttle cable adjuster lock nuts, and take off the throttle cable Remove the crankcase breather pipe Remove the speedometer cable mounting screw, take off the speedometer cable assembly Take off the engine sprocket cover Disconnect the ground wire...
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ENGINE Remove the lead wire of starter motor wire. Take off the spark plug cap Remove the muffler mounting bolt Remove the muffler mounting bolts then take off the muffler. Remove the engine front mounting bolt and engine lower hanging plate bolt , take off the engine lower hanging plate.
ENGINE ENGINE REMOUNTING The engine can be mounted in the reverse order of removal. Temporarily fasten the engine mounting bracket before inserting the engine mounting bolts. NOTE The engine mounting nuts are self-lock nuts. Once the nut has been removed, it is no longer of any use. Be sure to use new nuts and tighten them to the specified torque.
ENGINE CYLINDER HEAD AND VALVE REMOVAL Drain the engine oil, take off the engine. (Refer to page 3-2) Remove the generator cover cap and valve timing inspect- ing plug Remove the valve inspecting caps Bring the piston to top dead center. When removing cylinder head cover piston must be at top dead center on compression stroke.
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ENGINE Remove the camshaft sprocket bolts and detach the cam- shaft. The cam chain tensioner bolt is to be removed only when disassembling the engine Do not drop camshaft drive chain, pin and sprocket into the crankcase. Remove the cylinder head side nuts and cylinder side nuts. Loosen the cylinder head cover nuts diagonally, then detach the cylinder head.
ENGINE Take off the valve cotters from the valve stem. 11F14 018: Valve spring tools Take out the valve spring retainers inner springs and outer springs. Pull out the valves from the other side. Remove the oil seal. Removed oil seal should be replaced with a new one. Remove the spring lower retainer.
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ENGINE ROCKER ARM Check the inside diameter of the valve rocker arm and wear of the camshaft contacting surface. Rocker arm shaft O.D. (IN and EX): 12.0-12.018 mm 09900 20605: Caliper gauge CAMSHAFT The camshaft should be checked for runout and also for wear of cams and journals if the engine has been noted to produce abnormal noise or vibration or a lack of output power.
ENGINE Measure the runout with a dial gauge Replace the cam- shaft if the runout exceeds the limit. Camshaft runout limit: 0.1 mm 09900-20606: Dial gauge (1/100 mm) 09900-20701: Magnetic stand 09900-21304: V-block ( 100 mm) VALVE SPRING Measure the valve spring free length. Valve spring free length imit: IN.: 31.24 mm EX.: 33.58 mm...
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ENGINE Support the valve with “V” blocks as shown, and check its runout with a dial gauge. The valve must be replaced if the runout exceeds the limit. Valve stem runout limit: 0.05 mm 09900-20606: Dial gauge (1/100 mm) 09900-20701: Magnetic stand 09900-21304: V-block ( 100 mm) Place the dial gauge at right angles to the valve head, and measure the valve head radial runout.
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ENGINE INTAKE EXHAUST EXHAUST 30 , 45 15 , 45 Valve seat angle Valve width 0.9-1.1mm Exhaust side Intake side valve seat N-122 N-122 N-121 N-126 N-111 09916-21110: Valve reamer set Check the contact surface institute. If found any defective, service the valve seat. Damaged surface Uneven contact surface Using the 45 reamer, descale and cleanup the seat with...
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ENGINE Check the contact width. 09900-20103: Vernier calipers Valve seat width: 0.9-1.1 mm Width If contact width is too small, cut the valve seat with a 45 reamer to raise. If the valve seat contact width is too big, cut the valve seat out side 1/8 with a 30 reamer and cut the bottom 1/8 with a 60 reamer to lower.
ENGINE Clean and assemble cylinder head and valve components. Fill intake and exhaust ports with gasoline to check for leaks and worn seals. If any leaks occur, check the valve seat and face for burrs or other defects that could prevent the valve from fully seating. Gasoline is very explosive, be sure to keep the work area well ventilated.
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ENGINE Install the valve cotters with the special tool. 11F14 018: Valve spring tools CYLINDER HEAD COVER ASSEMBLY Clean the cylinder head cover throughly with detergent. Lubricate the rocker arm shaft with engine oil. Mount the rocker arm, rocker spring, flexuous washer and rocker arm to the cylinder head cover.
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ENGINE Install the four nuts and washers, tighten the nuts to specified torque. Cylinder head nut: 21-25 N•m Copper washer Copper washer Copper washer Copper washer Install the four cylinder side nuts, tighten the nuts to the specified torque. Cylinder side nut: 8-12 N•m Apply the Moly paste to the tip of cam Install the camshaft, sprocket and chain.
ENGINE CYLINDER AND PISTON CYLINDER REMOVAL Remove the cylinder head. (Refer to page 3-7) Remove the gasket, dowel pins and guide rod. Remove the cylinder. INSPECTION Clean the remaining gasket on the cylinder surface Check the gasketed surface of the cylinder for distortion with a stragihtedge and thickness gauge.
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ENGINE Decarbonize the piston. Using a soft-metal scrapper or discarded piston ring to decarbon the ring grooves of the piston. Do not use the steel brush or the piston will be scratched. INSPECTION Temporary install the piston rings to the suitable position with marked side upward.
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ENGINE Measure the conrod small end I D Conrod small end I.D.: limit: 14.04 mm 09900-20605: Caliper gauge Fit the rings in the cylinder, and measure each ring end gap with a thickness gauge. If any ring has an excess end gap, replace the ring.
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ENGINE Place a clean rag over the cylinder base to prevent piston pin circlip from dropping into crankcase, and then fit the piston pin circlip with long-nose pliers. Replace with a new piston pin circlip to prevent circlip slipping from position. End gap of the circlip should not be aligned with the cutaway in the piston pin bore.
ENGINE CLUTCH REMOVAL Drain the engine oil Remove the oil filter cover nuts, take off the oil filter cover Remove the oil filter. Remove the clutch cover screws diagonally, take off the clutch cover Remove the gasket and dowel pins. Remove the clutch spring bolts diagonally.
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ENGINE Remove the clutch drive plates and driven plates. Flatten the lock washer.. Hold the clutch hub with the special tool, remove the clutch hub nut and lock washer. 09920-53710: Clutch sleeve hub holder Remove the clutch hub and washer. Remove the primary driven gear, spacer and washer.
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ENGINE Drive plate claw width limit: 11.0 mm Checking claw width Measure each driven plate for distortion with a thickness gauge. Replace all driven plates if any of them exceeds the limit. 09900 20803: Thickness gauge Driven plate distortion limit: 0.1 mm Replace the drive and drive plates as a whole set which Checking distortion exceed the limit.
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ENGINE REASSEMBLY Reassemble the clutch in the reverse order of removal, pay attention to the following points: Install the washer, spacer, primary driven gear assembly, washer and clutch drive hub. Install the lock washer, tighten the clutch sleeve hub nut to the specified torque.
ENGINE OIL PUMP REMOVAL Remove the clip, oil pump driven gear and oil pump driven gear pin. Remove the oil pump. INSPECTION Rotate the oil pump by hand and check whether it moves smoothly. If the oil pump does not move smoothly, replace it. REASSEMBLY Apply a small quantity of engine oil to the inside the oil pump before assembly.
ENGINE GEAR SHIFTING SHAFT REMOVAL Remove gear shifting lever. Remove the clutch. (Refer to page 3-20) Remove the gear shifting shaft Remove the screws, gear shifting cam guide plate Remove the gear shifting driven gear , pawl , gear shifting pawl pin and return spring INSPECTION Check the return spring...
ENGINE GENERATOR & STARTING CLUTCH REMOVAL Disconnect the generator coupler. Remove the engine sprocket cover. Remove the starting motor by removing the bolts. Remove the generator cover Remove the gasket and dowel pins. Remove the generator rotor nut while holding the generator rotor with the special tool.
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ENGINE Remove the generator rotor and key with the special tool. 11F14-001: Rotor holder 11F14-003: M16 screw 11F14 005: Generator rotor remover M30 Do not damage the key slot and crankshaft when removing the key. Remove the starter clutch gear. Remove the roller , push piece , and spring...
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ENGINE INSPECTION Install the starter driven gear to the starter clutch and turn the starter driven gear by hand to inspect the starter clutch for a smooth movement. The gear turns one direction only. If a large resistance is felt to rotation, inspect the starter clutch for damage or inspect the starter clutch contacting surface of the starter driven gear for wear or damage.
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ENGINE Fit the key in the crankshaft key slot. When installing the key, take care not to damage the key slot and crankshaft. When installing the rotor, align the rotor key slot with the key on the crankshaft. Install the generator nut, tighten the nut to the specified torque.
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ENGINE CRANKSHAFT, TRANSMISSION AND KICKSTARTERSET. REMOVAL Remove the cylinder head and cylinder. (Refer to page 3-7) Remove the clutch and gear shifting shaft.(Refer to page 3- Remove the generator rotor and starting clutch. (Refer to page 3-27) Remove the neutral locate screw plug and oil filter cover. Do not take off the neutral locating screw plug (inner hexagon when drain the engine oil.
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ENGINE Fit the crankcase separator, so that the tool plate is parallel with the end face of the crankcase. Remove the right crankcase with the special tool. 09920-13120 : Crankcase separator WARNING WARNING WARNING The crankshaft and transmission components must remain in the left crankcase half, This is necessary because the gear shifting cam stopper is mounted on the left crankcase half and will be damaged if the...
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ENGINE INSPECTION Measure the big end of the conrod side clearance with a thickness gauge. Conrod big end clearance limit: 0.5 mm 09900-20803: Thickness gauge Support the crankshaft with “V” blocks as shown. Measure the crankshaft runout with the dial gauge. Crankshaft runout limit: 0.05 mm 09900-20606: Dial gauge (1/100 mm) 09900-20701: Magnetic stand...
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ENGINE Inspect the gear shifting hub guide slot. ● Replace the gear shifting hub if the guide slot is damage. Inspect each bush, gear inner surface and gear teeth face for abnormal wear or poor lubrication. Rotate the inner race by hand to inspect for an abnormal noise and a smooth rotation and inspect to see if the outer race is movable in the crankcase.
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ENGINE REASSMEBLY Reassemble in the reverse order of removal, pay attention to the following points: BEARING Install the bearings on the left and right crankcase with the special tool. 09913-70210: Bearing installer CRANKSHAFT Decide the width between the webs when rebuilding the crankshaft.
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ENGINE Never crankshaft into crankcase striking it with a plastic hammer Always use the special tool otherwise crankshaft alignment accuracy will be affected. TRANSMISSION Never reuse circlip. After a circlip has been removed from a shaft, it should be discarded and a new circlip must be installed.
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ENGINE Press-fit 2nd drive gear onto the counter shaft. Before reassembling, coat the internal face of the 2nd drive gear with Thread Lock super “1303B”and install it so that the length as shown in Fig. Countershaft length : 87.8-88.1 mm 99000-32030: Thread lock super "1303"...
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ENGINE NOTE: Two kinds of gear shifting forks, are used. They resemble each other very closely in extermal appearance and configuration. Carefully examine the i l l u s t r a t i o n f o r c o r r e c t i n s t a l l i n g p o s i t i o n s a n d directions.
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FUEL AND LUBRICATION SYSTEM FUEL COCK AND FUEL FILTER REMOVAL Turn the fuel cock to ” ” position shown in photo and disconnect fuel hose from the fuel cock. Place a clean pan under the fuel cock assembly, turn fuel cock to “...
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FUEL AND LUBRICATION SYSTEM REASSEMBLY Reassemble the fuel cock or fuel filter in the reverse order of removal. Pay attention to the following points: Gasket Install the fuel cock. WARNING WARNING WARNING Gasket must be replaced with a new one to prevent leakage.
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FUEL AND LUBRICATION SYSTEM CARBURETOR CARBURETOR CONSTRUCTION ITEM ITEM SPECIFICATION SPECIFICATION Carburetor type Bubbling jet BS26 Ø 3 Main jet 054G # 110 I.D. No. Idle air screw Needle 2,5/8 turn out 4DH41-2 Needle jet # 1.25 -0(390) Idle air jet Idle jet # 12.5 Idle...
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FUEL AND LUBRICATION SYSTEM REMOVAL AND DISASSEMBLY Disconnect the carburetor balance pipe Remove the carburetor clamp screw Remove the throttle cable Remove the fuel hose Remove the carburetor. Remove the carburetor diaphragm cover. Remove the spring, diaphragm and piston. Remove the float chamber body.
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FUEL AND LUBRICATION SYSTEM Remove the float pin screws. Pull out the float pin and remove the float and needle valve. Remove the main jet Remove the Bubbling jet Remove the idle jet NEEDLE VALVE INSPECTION If foreign matter is caught between the valve seat and the needle, the gasoline will continue flowing and cause it to overflow.
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FUEL AND LUBRICATION SYSTEM REMOUNTING Remount the carburetor by reversing the sequence of removal steps, and following adjustments and inspection are necessary after remounting the carburetor. THROTTLE CABLE PLAY Adjust the throttle cable play to be 0.5-1.0 mm. Adjust the throttle cable play as follows Slide the boot, loosen the lock nut of the throttle pulling cable, turn the adjuster...
FUEL AND LUBRICATION SYSTEM LUBRICATION SYSTEM Camshaft journal Conrod small end bearing and cam face Cylinder wall Camshaft Rocker arm shaft Conrod big end bearing Clutch release cam Countershaft bearing Oil filter Driveshaft bearing By pass Countershaft and gears Oil pump Drive shaft and gears Primary driven gear spacer...
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CHASSIS CONTENTS FRONT WHEEL FRONT ABSORBER STEERING STEM 5-12 FRONT BRAKE 5-18 REAR WHEEL AND REAR BRAKE 5-24 REAR ABSORBER AND REAR SWING ARM 5-30...
CHASSIS FRONT WHEEL CONSTRUCTION Front axle Front tire Spacer Front rim kgf•m Item N•m Dust seal Speedometer gear driver 18-28 1.8-2.8 36-52 3.6-5.2 Washer Oil seal Brake disc Speedometer gear box Oil seal Brake disc bolt Roller bearing Front axle nut Spacer...
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CHASSIS REMOVAL AND DISASSEMBLY Support the motorcycle by the center stand. Disconnect the front brake and speedometer cable Remove the front axle nut , take off the front wheel Do not operate the front brake lever when removing the front wheel. Remove the speedometer gearbox assembly Remove the front axle spacer and front wheel assembly dust seal...
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CHASSIS Remove the bearings on both sides with the special tool, take off the spacer. 09921-20240: Bearing remover tool INSPECTION OIL SEAL Inspect the oil seal for wear or damage, replace the oil seal if there are any defects. FRONT WHEEL AXLE Using the special tools check the axle shaft for runout and replace it if the runout exceeds the limit.
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CHASSIS REASSEMBLY Reassemble and remount the front wheel in reverse order of removal. Pay special attention to the following points. WHEEL BEARING Apply Super Grease ”A” to bearings before reassembly. 99000-25010: Super grease ”A” Install left wheel bearing first, then install the spacer and right wheel bearing with the special tool and removed wheel bearings...
CHASSIS BRAKE DISC Make sure that the brake disc is clean and free of any greasy matter. Install the brake disc, tighten to the brake disc bolts to the specified torque. Front brake disc bolt: 18~28 N•m Bend the lock washer to the brake disc bolt. SPEEDOMETER GEAR BOX Before installing the speedometer gear box, apply Super Grease A to it, then install it on the wheel.
CHASSIS FRONT ABSORBER CONSTRUCTION Oil lock piece O-ring Plug Oil seal Oil seal stopper ring Tube N•m kgf•m ITEM Oil seal Washer 35-55 3.5-5.5 Rebound spring Outer tube 20-26 2.0-2.6 Ring Seal ring Damper rod Front axle pinch bolt Damper rod bolt Inner tube...
CHASSIS REMOVAL AND DISASSEMBLY Remove the front wheel (refer to page 5-2). Remove the two bolts and dismount the front caliper Remove the four bolts and take off the front fender Remove the four handlebar holder clamp bolts, take off the handle bar , then remove the two front absorber cap bolts.
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CHASSIS Invert the absorber and stroke it several times to remove the oil. Remove the damper rod bolt by using the special tools and hexagon wrench. 11F14 010: Front absorber tools Remove the oil lock piece and damper rod with rebound spring.
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CHASSIS INSPECTION DAMPER ROD RING Inspect the damper rod ring for wear and damage. INNER TUBE AND OUTER TUBE Inspect the inner tube and outer tube sliding surface for any scuffing or flaws. SPRING Measure the spring free length. If it is shorter than the service limit, replace it.
CHASSIS OIL SEAL Install the oil seal to the outer tube by using the special tool as shown. 09940-50112: Absorber oil seal installer CAUTION Apply Super Grease lightly on the oil seal lip. ABSORBER OIL Pour the specified absorber oil into the inner tube. Front absorber oil capacity (each leg): 168±3 ml Absorber oil type: # 32 Hold the front absorber vertical and adjust the absorber oil...
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CHASSIS REASSEMBLY Reassemble the front absorbers in the reverser order of removal. Pay attention to the following points: Apply a small quantity of absorber oil to the O-ring the front absorber. Absorber oil type: #34 Install the front absorbers to the upper and lower bracket, tighten the front absorber cap bolts to the specified torque.
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CHASSIS REMOVAL Remove the front wheel. (Refer to page 5-2) Remove the front absorber. (Refer to page 5-6) Remove the two screws and take off the headlight. Disconnect the couplers and lead wires. Remove the lead wires from the headlight housing. Remove the two bolts and take off the headlight housing.
CHASSIS Remove the two bolts and take off the dashboard assembly. Remove the ignition switch cover. Remove the handlebar holder clamp bolts, take off the handlebar Remove the front absorber cap bolts and steering stem nut, take off the upper bracket. Take off the front absorbers.
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CHASSIS Remove the upper and lower steel balls. Number of balls: Upper: 22 pcs Lower: 18 pcs Remove the outer race fitted on the steering stem. This can be down with a chisel. Draw out the two inner races fitted to the top and bottom ends of the head pipe with the special tool.
CHASSIS REASSEMBLY Reassemble and remount the steering stem in the reverse order of removal, and carry out the following steps: INNER RACES Press in the upper and lower inner races with a special tool. 09940-34513: Steering race installer OUTER RACE Apply grease on the new lower oil seal Press in the lower outer race with the special tool.
CHASSIS Turn back the stem nut by 1/4-1/2 turn. 1/4-1/2 turn back 09910 60611: Universal wrench CAUTION CAUTION The adjustment will vary from motorcycle to another. Tighten the steering stem head bolts to the specified torque. Steer stem bolt: 35~55 N•m Install and ighten the front absorber bolts and the brake caliper bolts.
CHASSIS FRONT BREAK CONSTRUCTION N•m ITEM kgf•m Brake lever Pad set 8-12 0.8-1.2 Piston cup set Master cylinder clamping bolt 20-25 2.0-2.5 Brake light switch Brake hose union bolt 0.6-0.9 Brake hose Air bleeder valve 5-18...
WARNING WARNING The brake system of this motorcycle is filled with a Suzuki brake fluid. Do not use or mix different types of fuid such as silicone-based and petroleum-based fluid for refilling the system, otherwise serious damage will be caused.
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CHASSIS CALIPER REMOVAL Disconnect the brake hose from the caliper catch the brake fluid in a suitable receptacle. Remove the caliper mounting bolts and then take off the caliper. Never reuse brake fluid left over from the last servicing or stored for a long period of time. Do not operate the brake lever with the pads removed.
CHASSIS PISTON Inspect the piston surface for scratches or other damage. RUBBER PARTS Inspect the rubber parts for cracks and damage. If any defects are found, replace the affected parts. BRAKE DISC Visually inspect brake disc for cracks or damage, and measure brake disc thickness with a micrometer.
CHASSIS Tighten the brake hose union bolt to the specific torque. Brake hose union bolt: 20~25 N•m Bleed air from the brake fluid circuit after reassembly the cliper. (Refer to page 2-13) Brake fluid, if it leaks, will interfere with safe running and immediately discolor painted surfaces.
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Wash the master cylinder components with fresh brake fluid before reassembly. Brake fluid specification: Suzuki brake fluid When washing the components, use the specified brake fluid. Never use different types of fluid or Master cylinder cleaning solvents such as gasoline, kerosine, etc.
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CHASSIS REMOVAL AND DISASSEMBLY Support the motorcycle by the center stand. Remove the rear brake adjuster nut. Puff off the cotter pin, remove the torque link nut and bolt. Remove the rear axle nut. Loosen the chain adjuster lock nut and adjuster bolt, right and left.
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CHASSIS Remove the cushion from the wheel. Remove the right and left side wheel bearings. It will be easier to remove the left side bearing first. Take off the brake shoes. Remove the cam lever nut and bolt. Pull off the brake cam, washer, O-ring and cam lever. INSPECTION Play WHEEL BEARING...
CHASSIS AXLE SHAFT Using the special tools, check the axle shaft for runout and replace it if the runout exceeds the limit. Axle shaft runout limit: 0.25 mm 09900-20606: Dial gauge (1/100) 09900-20701: Magnetic stand 09900-21304: V block SPROCKET Inspect the sprocket teeth for wear. If they are worn as illustrated, replace the sprocket and drive chain.
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CHASSIS REASSEMBLY Reassemble and remount the rear wheel and rear brake in the reverse order of disassembly and removal, and also carry out the following steps. BEARING Apply grease to the bearings before installing. 99000-25010: Super grease ”A” Install the bearings by using the special tool. First install the bearing for right side.
CHASSIS Bend the lock washers. BRAKE CAM Apply grease to the brake cam. 99000-25010: Super grease “A” WARNING Be careful not to apply too much grease to the brake cam. If the grease gets on the lining, the brake slippage will result.
CHASSIS REAR ABSORBER AND REAR SWING ARM CONSTRUCTION Rear swingarm pivot shaft Rear torque link Dust seal Rear swing arm ITEM kgf m 50-80 5.0-8.0 Thrust washer Lock washer 10-15 1.0-1.5 Oil seal Bolt Spacer Chain buffer Spacer Rear swing arm pivot nut Rear torque link nut Washer 5-30...
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CHASSIS REMOVAL AND DISASSEMBLY Remove the rear wheel (Refer to page 5-24) Remove the rear absorber mounting nuts, take off the rear absorber, right and left.. Remove the chain case mounting screws, take off the chain case. Remove the swing arm pivot nut and draw out the shaft Remove the swing arm Pull off the cotter pin and remove the nut and bolt Remove the torque link...
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CHASSIS INSPECTION BUSHING Inspect the bushing for wear and damage. SWING ARM PIVOT SHAFT Using a dial gauge check the pivot shaft for runout and replace it if the runout exceeds the limit. Pivot shaft runout limit: 0.6 mm 09900-20606: Dial gauge (1/100) 09900-20701: Magnetic stand 09900-21304: V block REASSEMBLY...
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E L E C T R I C A L CONTENTS STARTER SYSTEM IGNITION SYSTEM CHARGING SYSTEM DASHBOARD 6-11 LIGHTS 6-12 SWITCHES 6-12 BATTERY 6-15...
ELECTRICAL STARTER SYSTEM DESCRIPTION The starter system is shown in the diagram below: namely, the starter motor, starter relay, starter button, clutch switch, ignition switch and battery. Depressing the starter switch(on the right handlebar switch box) energizes the relay, causing the contact points to close which connects the starter motor to the battery.
ELECTRICAL Measure the starter relay voltage at the starter relay connectors (between and W/B ) when the starter Not voltage Faulty ignition switch button is pushed. Faulty front brake light switch Faulty rear brake light switch Faulty starter button Voltage measured Poor contact of connector Open circuit in wiring harness Check the starter relay...
ELECTRICAL STARTER MOTOR INSPECTION CARBON BRUSH Inspect the carbon brushes for abnormal wear cracks or smoothness in the brush holder If either carbon brush is defective replace the brush with a new one Measure the length of the carbon brushes using a vernier calipers If the measurement is less then the service limit replace the brush with a new one...
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ELECTRICAL Measure the relay coil resistance between the terminals using the multi circuit tester. If the resistance is not within the specified value, replace the starter relay with a new one. 09900-25008: Pocker tester Tester knob indication: Resistance (Ω) Starter relay resistance: 3-6 Ω...
ELECTRICAL IGNITION SYSTEM DESCRIPTION in the capacitor discharged ignition system, the electrical energy generated by the magneto charges the capacitor. This energy is released in a single surge at the specified ignition timing point, and current flows through the primary side of the ignition coil. A high voltage current is induced in the secondary windings of the ignition coil resulting in strong spark between the spark plug cap.
ELECTRICAL IGNITION COIL Remove the spark plug cap Inspect the resistence of ignition coil with the pocket tester. 09900-25008: Pocket tester Tester knob indication: X1 Ω range Ω KΩ Primary: 3 4-4.6 Ω (tap-tap Secondary: 11.05-14.95 k Ω ( tap plug cap) Trigger coil Measure resistance between lead wires using multi-circuit tester.
ELECTRICAL CHARGING SYSTEM DESCRIPTION The circuit of the charging system is indicated in the figure, which is composed of an AC generator, regulator/rectifier unit and battery. The AC current generated from AC generator is converted by rectifier and is turned into DC current, then is charges the battery.
ELECTRICAL Continue the last page Incorrect Inspect regulator/rectifier. Faulty regulator/rectifier. Correct Incorrect Inspect wirings, Short circuit of wiring harness. Poor contact of couplers. Correct Faulty battery. Others Faulty regulator/rectifier. Battery overcharge Faulty battery. Poor contact of generator INSPECTION lead wire coupler. BATTERY LEAK CURRENT INSPECTION Remove the left side cover Turn the ignition switch to the OFF position.
ELECTRICAL CHARGING OUTPUT INSPECTION Remove the left side cover Start the engine, keep it running at 5 000 r/min, with lighting switch turned ON and dimmer switch turned HI position. Measure the DC voltage between the battery terminal and with a pocket tester.
ELECTRICAL FUEL LEVEL GAUGE REMOVAL Remove the fuel tank. (Refer to page 3-2) Remove the fuel level gauge. INSPECTION FUEL LEVEL GAUGE Remove the fuel lever gauge. (Refer to page 4-3) Check the resistance of each float position with a pocket tester.
ELECTRICAL DASHBOARD Remove the dashboard assembly. (Refer to page 5-13) Disassemble the dashboard assembly as follows. Upper case Speedometer cable Dashboard unit Bulb Lower case Wiring harness INSPECTION Using the pocket tester, check the continuity between Dashbaord lead wires. FUEL If the continuity measured is incorrect, replace the respective parts.
ELECTRICAL LIGHTS TURN SIGNAL LIGHT HEADLIGHT TAIL LIGHT/BRAKE LIGHT SWITCHES Inspect each switch for continuity with the pocket tester If any abnormality is found, replace the respective switch assemblies with new ones. 09900-25008: Pocket tester Test scale: Continuity IGNITION SWITCH ○...
ELECTRICAL BATTERY Battery SPECIFICATIONS Breathe pipe TYPE 12N7-4A Capacity 7 Ah Standard electrolyte S.G. 1.28 ± 0.01 20 C In fitting the battery to the motorcycle, connect the breather tube to the battery vent. INITIAL CHARGING Filling electrolyte Remove the short sealed tube before filling electrolyte. Fill battery with electrolyte (dilute sulfuric acid solution with acid concentration of 35.0% by weight, having a specific gravity of 1.28 at 20 C/86 F) up to indicated UPPER LEVEL.
ELECTRICAL Check the electrolyte level and add distilled water, as necessary, to raise the electrolyte to each cell’s upper level. Check the battery for proper charge by taking an electrolyte S.G. reading. If the reading is 1.22 or less, as corrected to 20 C, it means that the battery is still in a run-down condition and needs recharging.
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SERVICING INFORMATION CONTENTS TROUBLESHOOTING SPECIAL TOOLS TIGHTENING TORQUE SERVICE DATA 7-11 WIRE AND CABLE ROUTING 7-16 WIRING DIAGRAM 7-18...
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SERVICING INFORMATION TROUBLESHOOTING ENGINE Complaint Symptom and possible causes Remedy Engine will not start Compression too low or is hard to start. 1. Valve clearance out of limit. Adjust. 2. Worn valve guides or poor seating of valves. Repair or replace. 3.
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SERVICING INFORMATION Complaint Symptom and possible causes Remedy 1.Clutch control out of adjustment or too much play. Adjust. Dragging clutch. 2.Some clutch springs weakened. Replace. 3.Distorted pressure plate or clutch plates. Replace. 1.Broken gearshift cam. Replace. Transmission will 2.Distorted gearshift forks. Replace.
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SERVICE INFORMATION CARBURETOR Complaint Symptom and possible causes Remedy Trouble with 1.Starting jet is clogged. Clean. starting. 2.Starting pipe is clogged. Clean. 3. Air leakage from a joint between choke and carburetor. Check and retighten. 4. ir leakage at carburetor joint or vacuum tube joint. Check and retighten.
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SERVICE INFORMATION CHASSIS Symptom and possible causes Complaint Remedy 1. Steering stem nut over-tightened. Adjust. Steering feels too 2. Worn bearing or race in steering stem. Replace. heavy or stiff. 3. Distorted steering stem. Replace. 4. Not enough pressure in tires. Adjust.
SERVICE INFORMATION ELECTRICAL Complaint Symptom and possible causes Remedy 1. Defective ignition coil. Replace. No spark or 2. Defective spark plug. Replace. poor spark. 3. Defective trigger coil or ignitor unit. Replace. 1. Mixture too rich. Adjust carburetor. Spark plug soon 2.
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SERVICE INFORMATION BATTERY Complaint Symptom and possible causes Remedy 1. Not enough electrolyte. Pour distilled water, if the battery “Sulfation”, acidic has not been damaged and white powdery "sulfation" has not advanced substance or spots too far, and recharge. on surface of cell 2.Battery case is cracked.
SERVICING INFORMATION SERVICE DATA VALVE Unit: mm ITEM STANDARD LIMIT 25.5 Valve diam. 22.5 Valve clearance (when cold) 0.04-0.07 0.13-0.18 0.010-0.037 Valve guide to valve stem clearance 0.03-0.057 5.000-5.012 Valve guide I.D. IN.& EX. Valve stem O.D. 4.975-4.990 4.955-4.970 Valve stem deflection IN &...
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SERVICING INFORMATION CYLINDER + PISTON + PISTON RING Unit: mm ITEM STANDARD LIMIT 800 kPa 1 000-1 400 kPa Compression pressure 0.12 0 030-0.051 Piston to cylinder clearance 57.010-57.015 57.135 Cylinder bore Piston diam. 56.964-56.970 56.844 Measure at 8 mm from the skirt end 0.05 Cylinder distortion Approx.7.2...
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SERVICING INFORMATION CLUTCH Unit: mm ITEM STANDARD LIMIT 10-15 Clutch cable play 2.9-3.1 Drive plate thickness 11.8-12.0 Drive plate claw width 11.3 Driven plate distortion 29.45 Clutch spring free length TRANSMISSION + DRIVE CHAIN ITEM STANDARD LIMIT Primary reduction ratio 3.470 (59/17) 2.867 (43/15) Final reduction ratio...
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SERVICING INFORMATION ELECTRICAL ITEM SPECIFICATION NOTE Type NGK CR8E Spark plug 0.7 mm-0.8 mm Terminal - Ground or Primary 4 15 ± Ω Terminal - Terminal Ignition coil resistance Plug cap - Terminal or Secondary 13000±20% Ω Plug cap - Plug cap Bl-G Trigger Approx.110 Ω...
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LIMIT STANDARD Front fork stroke Front fork spring free length 385.5 Fork fork oil type SUZUKI fork oil #32 or equivalent fork oil Front fork oil capacity(each leg) 168±3 ml Rear suspension spring adjustment Swing arm pivot shaft runout FUEL +OIL ITEM STD/SPEC.
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SERVICING INFORMATION WIRE ROUTING 7-16...
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Do you have a question about the GN125F and is the answer not in the manual?
Questions and answers
Because in the oil change specifications it says oil capacity 850.filter change 950.overhaul.1300.Could you explain this to me?
The oil capacity for a Suzuki GN125F is as follows:
- Oil change: 850ml
- Filter change: 950ml
- Overhaul: 1300ml
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@Mr. Anderson
@Mr. Anderson . Pero porque dice 3 medidas de aceite diferentes.puedes explicarme bien eso.es decir que a medida que va realizando el cambio de aceite ahí que aumentarle más
Numéro pieces phare avant gn125f
Hello .At what RPM should the Suzuki 125 work in neutral? Because I don't see that part in the manual.
Dónde está el tornillo de ajuste del carburador GN125F