First loosen the two bolts that fix the front fork tube to the upper link plate, and then loosen the front fork tube cover.
Then, loosen the brake caliper bolts and the front axle, and then set the front end of the vehicle off the ground.
After the front end of the vehicle is lifted off the ground, loosen the brake caliper, the speedometer flexible shaft, the front fender, the front wheel and the parts connected to the shock absorber motorcycle rear shock absorbers(depending on the specific model).
Loosen the bolts that fasten the front fork tube, and pull down the front fork tube while turning. When replacing the shock absorber oil seal, it is best to replace the front fork tube on one side at a time to avoid mixing up parts.
Place the upper part of the front fork tube vertically on the vise. The clamped position of the vise is generally about 15cm away from the top of the front fork tube. Release the spring preload adjuster and carefully remove the front fork cover. When disassembling, put your hand on the front fork tube cover. This can prevent the lower spring from flying the front fork tube cover. After removing the front fork tube cover, remove the lower spring, and then discharge the damping oil in the front fork tube into the container. When discharging, tap the front fork tube lightly to drain all the damping oil. The front fork tube and the sleeve are connected together by the damping rod. To separate the front fork tube and the sleeve, the hexagon socket screws that fix the sleeve and the damping rod must be unscrewed. During disassembly, in order to prevent the damping rod from being together with the hexagon socket screws Rotate, you can flatten the top of the damper rod with a special tool, and clamp it with a nut of a suitable size welded under the spark plug sleeve.
After the damping rod is removed, although the front shock absorber has been disassembled, the front fork tube still cannot be removed. You need to remove the dust seal on the top of the sleeve to expose the spring metal flat below, and use a flat screwdriver to clamp the metal. Pry out. Use pliers to clamp the brake caliper to fix the casing, and at the same time, firmly grasp the front fork tube and pull it hard. In this way, the sliding sleeve under the front fork tube will squeeze the guide sleeve on the upper part of the casing and also squeeze the oil seal outward. .
After disassembling the front fork tube, clean and inspect it, and put all non-rubber parts in a solvent to remove the dirty oil. Look carefully at the chrome-plated layer on the front fork tube. Pay special attention to the place where the oil seal passes. If there are scars, scratches, and rust spots, you can use an oil-containing grinding stone to remove the rough edges. If the scars are serious and cannot be repaired, Replace the fork tube. At this time, judge whether the front fork tube is straight. The narrow edge of the straightedge is close to the front fork tube. If there is a gap between the straightedge and the front fork tube, replace the front fork tube.
Then check the sliding sleeve (TEFLON plated on the outside) at the lower end of the front fork tube. The sliding sleeve should be together with the front fork tube. There is no need to remove the sliding sleeve during inspection. Generally, it is only removed when replacing the sliding sleeve. If the bottom copper can be seen on the surface of the sliding sleeve, replace the sliding sleeve. The same is true for the inspection of the guide sleeve coated on the inner side of the upper part of the sleeve. Follow the order when replacing. After installing and stiffening the damping rod, slide the guide sleeve on the upper side of the sleeve over the fork tube, and then fit it into the corresponding groove of the sleeve. Then install the oil seal, it is best to have a special tool for installing the oil seal, and the useless bearing seat of the model may just be used to install the oil seal. Carefully use a flat screwdriver and weight to tap lightly around the bearing seat to fix the oil seal in the corresponding position. Before installing the oil seal, apply grease to it, and then install it in the same way.
Inject a certain amount of damping oil (generally a combination of 50% turbine oil and 50% transformer oil) into the front fork tube. If you feel that the front shock absorber is very soft, it may be due to insufficient elasticity or insufficient damping. At this time, it is best to use a damping oil with a higher viscosity. Mixing different shock-absorbing oils is not a good way, because the viscosity of the shock-absorbing oil after mixing the shock-absorbing oil with the viscosity of 10 and the shock-absorbing oil with the viscosity of 20 is not the viscosity of the shock-absorbing oil with the viscosity of 15. The viscosity of the shock-absorbing oil may be around 13.3. In any case, using a damping oil with a higher viscosity, the slower the damping recovery will be, and the compression of the damping will be smaller. With a stronger spring, you will feel a significant improvement in the performance of the front shock absorber.
After measuring the shock absorber oil level, stretch the front fork, and then install the spring, spacer and fork cover. Install the front fork tube into the lower link plate, and then fasten the shock absorber to the lower link plate with fixing bolts. The method of replacing the oil seal of the shock absorber on the other side is the same as this.