Oil seal the lip gently to avoid damaging it.
When pressing fitting the oil seal into the bottom case, it is recommended to insert the inner tube into the bottom case and press fit the oil seal while using the inner tube as a guide. When working, the oil seal is incorporated from the top of the inner tube, but be careful because there have been cases where the oil seal is pressed against the edge of the tube end, causing damage to the oil seal lip.
To avoid such mistakes, it is recommended to cover the top of the inner tube with a cut piece of plastic bag, apply a thin layer of silicone rubber grease, and set the oil seal in place. The plastic bag protects the seal lip and prevents damage to the seal. Plastic bag pieces and silicone rubber grease are essential for SANMECA.
The bottom bolt gasket also replaced with a new one in principle
There are replacement parts and consumable parts when disassembling and maintaining the damper pipe. Replace them with new parts each time you disassemble the unit. However, sometimes we forget to order new parts. In such cases, instead of reusing the parts as they are, you may be able to reuse them by polishing them on an oil stone surface to remove burrs from the gasket washers and polish the gasket surface smooth, so you should keep an oil stone in your possession. When using the oil stone, keep in mind to spray engine oil or lubricant spray on the polishing surface and rub it.
Without lubricant, it is impossible to polish cleanly. Also, when tightening the damper pipe, use a medium-strength thread locker in combination with a thread locker, and be sure to tighten the damper pipe firmly.
POINT
Point 2 - Damper pipe spinning can be avoided by using the holder tool
Point 3 - Silicon rubber grease is a necessity for Sanmeka when assembling rubber parts.
Point 4 - Oil stones are useful for improving the surface accuracy of parts and deburring, and we want to have a variety of shapes.
The most common cause of oil leakage in front forks is often pain in the oil seal lip that seals the sliding portion of the inner tube. When replacing this oil seal, there are a surprisingly large number of areas that require attention. In the case of models from the 1980s onward, the oil seal can be removed by hooking it to the inner metal set at the lower end of the inner tube and sliding the inner tube out with a "scoot, scoot" motion. In many cases, the oil seal must be removed while it is still in the bottom case.
In such types of cases, the bottom case may be damaged by overworking during the operation.
Particular attention should be paid to the forcible removal of the bottom case using a large screwdriver or tire lever. When a screwdriver or tire lever is used, the lever has only one fulcrum, so the force is concentrated there, often deforming the bottom case or, worse, causing it to crack. The fork seal puller, a special tool, distributes the force applied to the fulcrum and allows the oil seal to be pulled out more smoothly.
When press-fitting an oil seal, it is recommended to insert the inner tube into the bottom case with or without the inner metal and use the oil seal driver with the inner tube as a guide. When using the oil seal driver, use a screwdriver that matches the size of the oil seal. In the case of a standard-size oil seal driver, the three pressing points should be set at intervals of 120 degrees to ensure smooth insertion of the oil seal without tilting it. When hammering in, a very thin layer of silicone rubber grease must be applied to the outer circumference of the oil seal.
When tightening and fixing the damper pipe, it is the centering of the damper pipe that requires more attention than the pipe offerings. When tightening, do not tighten and fix the damper pipe all at once, but keep the inner tube in the full bottom state, and the damper pipe + oil lock piece, which is called a damper pipe + oil lock piece, While keeping the damper pipe centering, tighten the damper pipe temporarily for the first time, and then tighten it with the specified torque after reconfirming the centering by rotating the inner tube in a circular motion while maintaining the full bottom position.
If the damper pipe is not in the center of the bottom case, the front fork may not work as well as it should. Also, if the inside of the disassembled bottom case is dirty, the damper pipe cannot be fixed securely, so be sure to thoroughly clean the inside of the bottom case and especially the bottom area before restoring it.
