User manual DAELIM SC125 SERVICE MANUAL

[. . . ] HOW TO USE THIS MANUAL This manual describes effective maintenance procedure for the SC125 manufactured by DAELIM Motor Co. , Ltd. To ensure safety and optimal operating conditions of the vehicle, carry out regular inspections according to the maintenance schedule (Section 3). Sections 1 through 3 provide information on overall vehicle; section 4, assembly and disassembly procedures for external components, and section 5 describes maintenance procedure for the engine, frame and electrical systems. To facilitate use of this manual, each page starts with disassembly and system diagrams, service information, and troubleshooting guide. [. . . ] Rotate the reamer clockwise, never counterclockwise when inserting and removing. TOOL : VALVE GUIDE REAMER Measure and record each valve guide inner diameter. SERVICE LIMIT : 5. 030 mm Measure the guide-to-stem clearance with a dial indicator while rocking the stem in the direction of normal thrust. SERVICE LIMIT : IN : 0. 080 mm EX: 0. 100 mm Measure the inner diameter of the new valve guide. If the clearance is not within the service limit, replace the valve. REPLACEMENT NOTE Refinish the valve seats whenever the valve guides are replaced to prevent uneven seating. Use temperature indicator sticks, available from welding supply stores, to be sure the cylinder head is heated to the proper temperature. CAUTION Using a torch to heat the cylinder head may cause warping. WARNING Wear insulated gloves to avoid burns when handling the heated cylinder head. 9-7 CYLINDER HEAD / VALVES Support the cylinder head and drive the old guides out of the combustion chamber side of the cylinder head. TOOL : VALVE GUIDE DRIVER CAUTION Avoid damaging the head when driving the valve guide out. Drive the new guide in from the camshaft side of the cylinder head while the cylinder head is still heated. TOOL : VALVE GUIDE DRIVER When reaming new valve guides, insert the valve guide reamer from the combustion chamber side. NOTE Take care not to tilt or lean the reamer in the guide while reaming. Otherwise, the valve is installed slanted, that causes oil leaks from the stem seal and improper valve seat contact and results in the valve seat refacing not able to be performed. Use cutting oil on the reamer during this operation Rotate the reamer clockwise, never counterclockwise when inserting and removing. TOOL : VALVE GUIDE DRIVER Reface the valve seats and clean the cylinder head thoroughly to remove any metal particles. VALVE SEATS INSPECTION Clean all intake and exhaust valves thoroughly to remove carbon deposits. Apply a light coating of Prussian Blue to each valve face. NOTE Tap the valve against the valve seat serveral times with the valve guide reamer, without rotating the valve, to check for proper valve seat contact. 9-8 CYLINDER HEAD / VALVES Remove the valve and inspect the valve seat face. The valve seat contact should be within the specified width and evenly all around the circumference. If the valve seat width is not within specification, reface the valve seat. NOTE Valve faces and stem tips cannot be ground. If a valve face or stem tip is rough, worn unevenly, or contacts the seat improperly, the valve must be replaced. Measure the valve seat width. STANDARD VALUE : 0. 8 -1. 0 mm SERVICE LIMIT : 1. 4 mm VALVE SEAT REFACING Reface the worn valve seat by using valve seat cutters and grinders. NOTE Follow the refacer manufactuer's operating instructions. Be careful not to grind the seat more than necessary. Using a 45 degree cutter, remove any roughness or irregularities from the seat. Using a 37 degree cutter, remove valve seat material. of the existing 9-9 CYLINDER HEAD / VALVES Using a 55 degree cutter, remove the bottom old seat. of the Using a 45 degree cutter, cut the seat to the proper width. If the contact area is too high on the valve, the seat must be lowered using a 37 degree flat cutter. Refinish the seat to specifications, using a 45 degree finish cutter. If the contact area is too low on the valve, the seat must be raised using a 55 degree inner cutter. Refinish the seat to specifications, using a 45 degree finish cutter. 9-10 CYLINDER HEAD / VALVES After cutting the valve seat, apply lapping compound to the valve face, and insert the valve with a valve guide reamer. NOTE Do not excessively press and turn the valve to set it as it may cause damage. The seat surface may become worn on one side if the valve is set in the same position. Take precautions not to allow compound to get into the clearance between the stem and guide while the valve is being set. IN, EX VALVE Install new stem seals. NOTE Replace the stem seals with new ones whenever a stem seal is removed. Lubricate each valve stem with molybdenum disulfide grease and insert the valve into the valve guide. CAUTION Turning a valve too fast can damage the stem seals. Install the spring seats, valve springs and retainers. NOTE For valve spring with varying pitch, install the valve springs with the narrow pitch end facing down. Compress the valve springs with the valve spring compressor and install the valve cotters. CAUTION Compressing the valve spring more than necessary when installing the valve cotters may cause loss of valve spring tension. TOOL : VALVE SPRING COMPRESSOR 9-11 CYLINDER HEAD / VALVES Tap the valve stems gently with a soft hammer to firmly seat the cotters. CAUTION Take necessary precautions not to damage the valve. Install the spark plug. TORQUE : 1. 2 kgf m CYLINDER HEAD ASSEMBLY Clean any gasket material from the cylinder mating surface. Install the dowel pins and new gasket. Install the cylinder head. 9-12 CYLINDER HEAD / VALVES CAMSHAFT ASSEMBLY Apply engine oil to the rocker arm shaft, and assemble the rocker arm to the camshaft holder. Tighten the rocker arm shaft with 5mm bolts, and align the bolt hole of the camshaft holder with the fitting side of the rocker arm shaft. Check the camshaft assembly for abnormal condition, and place it on the cylinder head. Put the cam chain on the cam sprocket. Slowly rotate the crankshaft counterclockwise, and align the T mark of the flywheel with the index mark of the RH. crank case cover. CAUTION Take precautions not to allow the cam chain to come off the camshaft timing gear while turning the camshaft. 9-13 CYLINDER HEAD / VALVES Apply engine oil to the camshaft, and install it on the cylinder head with the cam thread facing downward. [. . . ] Replace the blub. TAIL LIGHT /REAR WINKER BULB REPLACEMENT Remove the body cover and tail light. Install in the reverse order of removal. NOTE Pay attention not to damage the lens. Do not apply excessive force when removing the lens. 18-2 LIGHTS/METER/SWITCHES STARTER SYSTEM MAIN SWITCH REMOVAL Remove the front cover. Install in the reverse order of removal. INSPECTION Check for continuity between the terminals There should be continuity between the O---O positions on the continuity chart. COLOR BLACK/WHITE TERMINAL OFF ON LOCK GREEN RED BLACK HANDLE BAR SWITCH INSPECTION Remove the back mirror. [. . . ]