The sluggish handlebar switch could be recovered with an overhaul to restore its functions. It's no surprise that you can switch the blinkers and headlights high and low at the touch of a switch. However, on older motorcycles, the switches may be sluggish or the lights may not be as responsive as it should be. In that case, check the contacts inside the switch box. If you find that the contacts are worn out due to poor lubrication, or that the contacts are corroded due to moisture ingress, appropriate measures must be taken.
The switch box is a den of friction and wear!
The photo shows the KAWASAKI KZ1000J left-hand drive switch. Compared to modern motorcycles, the parts of the switch box were rugged and less smooth to operate. On top of that, the movement of the switch is quite austere after 40 years of use. The plastic knobs could be damaged if you continue to use it forcibly, so maintenance is required.
The handlebar switch is the center of the electrical system, which controls the indicator lights, horn, and headlight high/low beam dimmer switches. When each switch is slid or pushed to the left or right, the contacts inside the switch are switched or contacted to operate the electrical components.
The contacts are very important to the electric circuit. Poor lubrication can cause wear if the switch is not lubricated properly, and poor contact can occur if symptoms develop. Also, if rainwater continues to infiltrate into the switch box, it will cause the contacts to corrode, and if the grease is gone on the sliding and shaft parts, the moving parts other than the contacts will be worn out.
These failures are less likely to occur on newer, older motorcycles, but once the motorcycle is over 10 years old, with or without maintenance and repair can affect the condition of the parts.
The only way to get a switch box as a component is to purchase it in assembled condition. However, OEM parts for older models are often discontinued and even more expensive than you might think.
That is why it is important to maintain and grease up the contacts and moving parts before you replace the entire switch box.
POINT
- Beware of deterioration of contacts and moving parts due to aging.
- Individual parts inside the switch are difficult to obtain.
The structure may be simple, but the assembly process may be complex.
I'm sure some of you have already taken the switch box on and off, but the box itself needs to be carefully disassembled and cleaned. The mechanism is simple, but the assembly is complicated. There are no instructions for disassembly of the switch box in the service manual, so you need to check your motorcycle switch carefully before you do the work.
Many types of switch boxes are not so complicated in structure. The left switch box for the Kawasaki KZ1000J around 1980, which taken as a sample, has a blinker, hazard, dimmer switch and horn button. The blinker switch is not push-cancel type as common today, but simply slide it left and right.
If I classify switches as electrical contacts in terms of mechanics, they are knobs that are touched by the rider's finger, movable parts that move in conjunction with the knob, and contacts that are built into the movable pieces. The counterpart of the movable contact are fixed contacts attached to a board that is secured inside the switch box (each part has a different name).
There are simple contacts such as a horn button that interrupts the flow of electricity in one system, and switches that switch between high beam and low beam operations such as a dimmer switch, and each has a different structure. In addition, the movable part to which the contacts are attached often has a built-in mechanism to modulate the feel of operation.
As a result, the movable parts and the fixed contacts are often a complex combination of "contacts", "springs" and "balls". As mentioned earlier, switch boxes are sold in an assembled state (some models are sold with only a knob that can be replaced from the outside of the switch box), and if a small spring or steel ball is lost during disassembly, it is impossible to restore it.
Also, it is natural that the switch will not work properly if each part is assembled in the wrong order. The electrical components will also not light up properly, so it is necessary to fully observe how each part is assembled when assembling, and if necessary, disassemble it with great care, leaving a picture on your phone or other devices.
This switch has a plastic knob inserted into a plastic movable parts and hooked up with a claw. The knob will come off if the claw is broken, so do not use excessive force when disassembling.
Clean the removed internal parts with parts cleaner and polish with non-woven cloth or steel wool if there is any roughness or corrosion on the contacts.
POINT
- There are many small parts in the switch box
- It is useful to keep a picture of the motorcycle before disassembly.
Surprisingly smooth with cleaning and greasing up
The contacts only fit where it match, but if the springs that apply tension to the steel ball have different lengths, be careful not to set the contacts in the wrong place. If the spring is shorter than the prescribed length, the clicking sensation will be reduced, and if the spring is longer, the movement of the knob will be worse.
The small bakelite that goes behind the contact is an important insulator. If you forget to put it in, the spring and steel ball will become a conductor and cause a short circuit. If it is built as a stock part, do not forget to insulate it when you restore it.
Disassembly of a switch box that is 40 years old from manufacture requires a variety of precautions. The most important thing to watch out for is damage to plastic parts that have hardened with age. This Kawasaki's switch knob is made of plastic, both the dimmer and the blinker are made of plastic, combined with a plastic movable parts.
If the plastic parts are broken, it will be troublesome, so we have to carefully observe the structure of the switch box and do not apply excessive force to it. Also, when removing the movable parts and the fixed contacts from the switch box, be very careful not to lose the springs and balls. Working in a large plastic bag is also a good idea to prevent parts from being lost.
Carefully clean the removed parts, checking for wear and corrosion in the contact points for contacts, and for grease and steel ball adhesion for movable parts. Grease, which has been used for many years, may be just like mud, so carefully remove it using parts cleaner, cotton swabs and a brush. Also, if the contacts are dirty with an oxide film, you can polish it with steel wool or a non-woven cloth to prevent future contact problems.
After the parts have been cleaned, silicone grease is applied to the parts to lubricate and prevent rust. The silicone grease does not have a negative effect on the plastic material, so it is safe to use, but not too much, as it may increase the resistance. When restoring each component to the switch box, it is necessary to check more carefully than when disassembling the switch box to make sure that the contact terminals and insulating bakelite are not misaligned and that the steel balls and springs are in the correct order.
When the grease in the indicator switch deteriorates, you may feel the resistance as if you're kneading the viscosity, but cleaning and proper grease application will give the operation a tickle of moderation and make the knob move much more smoothly. Since everything is inside the switch box, it won't look any different after work, but it should be very satisfying as it's a part of the motorcycle that is operated constantly while riding.
If you feel reluctant to operate the switch, you should give it a try. However, it is important to understand that if the internal parts are damaged or lost, you will likely have to replace the assembly.
Apply silicone grease to the steel ball that is assembled to the movable parts. If it is too thin, it will wear out the plastic parts, and if it is applied too much, it will cause resistance and make them heavy, so the amount should be moderate.
A polished contact surface is smooth when slid in, and the application of grease increases the smoothness of the contact. By doing this, the operability of the switch will be greatly improved.
POINT
- Silicone grease is the best lubricant for plastic parts
- Cleaning and greasing clearly improve operability
See KAWASAKI Moto Index Page
See Accessories for KAWASAKI Z1000J (KZ1000J)
