Cable maintenance is essential to reduce friction loss. When lubricant is hard to pass, try pulling it with a syringe.

Since the lubrication of the cable affects the feeling of the throttle and clutch, it is important to keep the oil content inside the cable intact for smooth operation at all times. When injecting high-viscosity cable grease after cleaning the inside of the outer cable with parts cleaner, etc., do you ever worry about whether the grease is being spread properly?　In such a case, you can use a syringe to suck out the grease from the outlet side to ensure reliable grease up.

Grease up affects not only the operability but also the life of the cable.

The control cable (wire), which is also used for the throttle, clutch, and brakes if the vehicle has drum brakes, is the most basic part that transmits the rider's operating force to the bike. The inner cable is made of a stainless steel material with a number of fine core wires strung together, while a resin tube made of Teflon or polypropylene is used inside the outer cable to transmit power without friction loss, even when the cable is bent. Even though advances in materials have improved the slippage between the inner and outer cables, the wires that rub against each other over a long period of time still require maintenance, periodic cleaning and greasing. Although the cable will operate without maintenance, poor lubrication can increase friction loss, making throttle and clutch operation heavier. Although it is difficult to notice because the friction loss does not suddenly increase one day, but rather progresses gradually, it can make it difficult to handle delicate operations such as opening the throttle slightly from idle or subtly adjusting the speed of a low-gear half-clutch. In addition, the inner and outer cables rub strongly against each other at bends, which can cause wear and tear on both cables, resulting in disconnection. In other words, just like engine oil and chain oil, control cables must be maintained.

Cleaning before greasing is important.

To keep the cables in good condition, it is effective to lubricate the gap between the outer cable and inner cable with cable grease or other lubricant. The key to this process is cleaning prior to lubrication. Although the working surfaces of the cables are not exposed to the outside like the drive chain, dirt is generated where they rub against each other, and injecting oil on top of them will not provide sufficient lubrication. Comparing the viscosity of parts cleaner and cable grease, the cleaner naturally has lower viscosity and higher permeability, and can wash away dirt in the cable. Injecting fresh grease or oil on top of the cleaner will form a lubricating film on the contact area between the inner and outer cable inner surfaces, resulting in a reduction of friction loss and wear. Although dirt on the inner surface of the cable cannot be visually confirmed, cleaning should be performed first before greasing for maintenance.

Forced injection of spray chemicals or slow injection by gravity drop?

After cleaning with parts cleaner, etc., there are two ways to inject grease or lubricant into the cable: "cable injector" or "gravity drop". When using spray-type cable grease, a cable injector can be attached to the cable to use the sprayer's gas pressure to force grease into the cable. Depending on the shape of the adapter between the fitting at the cable end and the injector, the sprayed grease may not pass through the wire properly and may blow back at the injector part, so the installation position may need to be adjusted. Even in such cases, if the sprayed grease spurts out from the opposite side of the cable, it can be judged to have been distributed inside the cable. The gravity drop method, on the other hand, uses gravity to inject grease or lubricant into a plastic bag that is wrapped around the end of the cable with tape. This method generally requires the cable to be removed from the car body to create a height difference between the entrance and exit, and takes more time than spraying, but it is effective when the injector does not fit due to the shape of the cable fittings.

If you suck it out from the exit side, it will surely go inside the cable.

The gravity-drop injection method is effective in improving work efficiency: "syringe sucking out". If the fittings on the injection side are filled with lubricant and the outlet side is under negative pressure, the lubricant will be sucked into the cable and spread to every corner. Although a syringe was used here, the same effect can be achieved by generating negative pressure with a vacuum tester (hand pump), which is useful for bleed air from brakes. If there is an adjuster in the middle of the cable, secondary air may enter there and prevent the lubricating oil from being sucked out. Incidentally, sealing the adjuster part is effective in preventing the oil from spurting out from the middle of the cable even when using an injector for injection work. It is good to wait slowly for the lubricant to drip down from the end of the cable that has been removed from the vehicle body and hung vertically, but it may be even better to know that the work time can be shortened by using negative pressure together.

Excess oil inside the cable is blown away by air blow.

Grease and lubricant injected into the cable helps reduce friction loss, but if excess oil gradually flows out and adheres to the carburetor, engine, or brake area, it can cause contamination and trouble. Therefore, it is recommended to lightly blow air inside the cable after lubrication. However, it is acceptable to blow off the oil that flows out from the ends, as it does not help lubricate the cable. When installing cleaned and lubricated cables in the car body, it is important to pay attention to the layout of the cables. Both the throttle and clutch cables bend as you turn the handlebars from side to side, and interference with the front forks and gasoline tank can affect handling. If you remove the cable from the car body, lubricate it and restore it, and it is heavier than before, ......, recheck to see if it is not pinched between the gas tank and the frame, or if its freedom is impaired by interference with the harness. Do not underestimate the importance of the cables, and keep in mind that careful attention to detail will ensure that the vehicle remains comfortable and smooth to operate.

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