Basic Fixing of Exterior Parts | How to Remove Air Cleaner Element By Using a Quick Fastener

Unlike in the days of old and out-of-print motorcycles, where the engine and carburetor were visible and the air cleaner box was behind them, the majority of air cleaner boxes on today's motorcycles are stored behind the gas tank and cowl. Plastic quick fasteners are widely used to secure the exterior parts of modern motorcycles. At first glance, it's difficult to understand how to attach and detach these mysterious parts, but knowing how to handle them can come in handy, so let's take this opportunity to learn.

Light, low cost, and reliable quick fasteners

Debuting in 2011, the Kawasaki Ninja 400R is a 400cc model with the same frame configuration and two-cylinder engine as the export ER-6 series. The Ninja 400, which was fully redesigned for 2018, has a sharper design reminiscent of the ZX-10R, while the 400R features an upright position and orthodox design that shows its true potential for city riding and two-rig riding.

Various changes occurred when the intake system changed from a carburetor to fuel injection, but the fact that the concept of oil level disappeared is a major point. In the carburetor era, the oil level of gasoline, which is determined by gravity, was always parallel to the ground regardless of whether the layout of the engine was horizontal (horizontal) or inclined (downdraft).

However, fuel injection, which uses a fuel pump to supply gasoline, eliminates the need for a float chamber, allowing the throttle body to be designed in any posture, and the positional relationship between the engine and air cleaner box has changed dramatically from the carburetor era.

Even in the carburetor era, there were models with a combination of a forward-leaning engine and downdraft carburetor where the air cleaner box was located under the gasoline tank, but today, many models use a combination of a throttle body with fewer installation restrictions and an air cleaner box with a larger capacity to reduce intake noise. However, many models now have the air cleaner box installed under the gasoline tank to reduce intake noise.

As a result, installing and removing the air cleaner element, which used to be easily accessible by removing the seat and side covers, has become a major task with the gas tank removed. Also, the air cleaner box covers the head cover of the engine, making it more difficult to remove the spark plug than on older motorcycles.

The exterior parts of these modern motorcycles are often assembled using a quick fastener. When you think of a quick fastener, old-school riders may think of a metal part that twists 90 degrees to hold the cowl in place, but the quick fastener here is made of plastic.

If the material to be fixed is metal, as in the case of attaching a side cover to a frame, a metal nut can be welded on or a female thread can be cut in the material itself. This used to be the case, but it would add weight and cost to go to the trouble of installing nuts and fixing with metal bolts and screws to join plastic panels together.

This fastening method has been used since the 1980s on scooters, where the exterior parts are now made up of a combination of plastic covers, but since the mid-2000s it has also been used extensively on sportbikes and trail models. Quick fasteners, which are simply holes in the cowl and covers where they are joined, can be inserted and fixed with a simple one-touch operation, and have all the advantages of being lightweight, low-cost, and easy to assemble.

However, riders who have never seen a quick fastener before may be confused about what it looks like and how to put it on and take it off. There are two types of quick fasteners: rivet and screw. In this section, we will explain how to install and remove the rivet type quick fasteners, and then remove the gas tank to install and remove the air cleaner element.

Push in the thin pin in the center to release the lock.

Rivet-style quick fasteners are unlocked by pushing in the pin in the center of the fastener head. Gently push it in with a hex wrench or precision screwdriver, as using a sharp tool such as a pick tool may damage it.

When the pin is pushed in, the open claw is squeezed to release the tension, and the fastener head is lifted slightly off the surface of the part. You don't need to use a tool, just hook the end of the claw and it will come off easily.

The trim at the bottom of the gas tank is inserted into the grommet on the side of the tank with two pins. The rear of this part and the seat cowl are held together with quick fasteners.

The vehicle used for this work is Kawasaki Ninja 400R 2012 model. The air cleaner element for this model is a urethane sponge type, and according to Kawasaki's maintenance notes, it should be replaced every 2 years under standard conditions. The filter paper type element should be replaced every 36,000km, and the viscous type element, which is permeated with oil, should be replaced at 18,000km. Considering the length of time that has passed since the motorcycle was new, it is probably a good time to replace the element.

When removing the petrol tank, the trim under the tank is removed, but a rivet-style quick fastener is used to join the trim to the seat cowl. The surface of the quick fastener is smooth and there is no part that can be turned with a tool such as a screwdriver. To remove this part. Press in the center round part with the tip of a thin screwdriver or hex wrench.

A quick fastener is made up of two parts, the round part being a stepped pin. The pin is combined with the outer fastener, and when the pin is tight, the claw at the end of the fastener expands to lock it in place, and when the pin is pushed in, the claw squeezes out.

Once you understand how it works, it's really quite simple, but if you get stuck at this point, it's very difficult to move forward. It's not as secure as a bolt and nut, so if you try to pry the fastener off without pushing the pin in, you may damage the cowl or break the fastener claws.

Like bolts and nuts, the quick fasteners used to assemble and secure the exterior parts of both sportbikes and scooters come in a number of sizes, depending on the thickness of the material and strength required for the parts to be joined. If you take advantage of the fact that they are so easy to remove by pressing the pins together and putting them all together in a tray, it can be difficult to know which pin to use in which hole when restoring the fastener.

It is obvious that a large pin will not fit in a small hole, but the opposite pattern is possible, so be careful. If the hole is too big for the pin, the panel or cowl will be out of alignment with each other, which may cause minor scratches on the joint, or the parts may creak each other while riding, causing abnormal noise.

In the case of this Ninja 400R, there are only a few quick fasteners to pull out when removing the gas tank, but some models may remove the tank top moldings or even the inner cowl, so in such cases, it is best to check the size of the fasteners and make sure the installation location is clear.

The gasoline tank is not fixed to the frame with quick fasteners, but with steel bolts, as expected. When the tank is lifted, the joint between the fuel pump and the hose has to be disconnected, which is unique to fuel injection. Depending on the model, the gasoline discharged from the fuel pump is under the pressure of 200 to 400kPa. Therefore, the connector is equipped with a locking mechanism to prevent the pump and hose from being disconnected easily.

Locks should not be easy to remove, which is why they can be complicated to remove. In the case of this Ninja, it can be pulled out by sliding the lock of a conspicuous color, but there is a rubber part that puts tension on the lock to prevent it from coming off, or there is a type that pushes the nail of the coupler after removing the physical lock, so it is necessary to remove it after carefully observing the parts composition of the joint part. The pressure left in the hose from the pump may cause a small amount of gasoline to spurt out when the joint is removed, so it is also important to always place a rag under the joint area before removing the hose.

When the gasoline tank is removed, the air cleaner box finally appears underneath, and the urethane sponge air cleaner element can be removed. The importance of the air inlet is the same for both carburetors and injectors, so be sure to check it regularly, even though it takes time to attach and detach ancillary parts.

The gasoline tank mount is fixed with bolts. The rubber damper sandwiched between the brackets is an important part to prevent vibration from the engine and vehicle body from being transmitted to the tank, so it should be replaced if it has hardened over time or if the rubber has dented to the point where it no longer serves its purpose.

Once the tank mount bolts are removed, lift the back end of the tank just high enough that the fuel hose and pump wiring won't stick out and disconnect the pump wiring coupler.

The joint between the fuel pump and the hose has a locking mechanism to prevent it from coming off easily. In the case of this motorcycle, the lock can be unlocked by sliding it with a thin screwdriver.

The coupler part and the fuel pump delivery pipe are both plastic parts, so do not pry or twist them forcibly when pulling them out. A small amount of pressurized gasoline may spray out when the hose is pulled out, but if the lock is properly removed, it should pull straight out. If it doesn't, there may be a nail on the hose that is not part of the locking mechanism.

Once the fuel hose joint is disconnected, the fuel tank will lift up significantly, so pull out the rubber hoses leading to the tank, such as the breathing hose and drain hose, and remove the tank.

Remove the cover on the top of the air cleaner box and pull out the air cleaner element. The element of this motorcycle is thin, so the urethane sponge type is used. The air cleaner element is dirty with not only dust and dirt but also blow-by gas from the crankcase, so it needs to be checked and replaced regularly.

When installing, pull the pin toward you and then set it in the hole.

By pushing the pin back and letting it stick out of the fastener head, the jaws will deflate and allow it to go through the hole. If you make the mistake of trying to push the pin back into the hole when it is only flush with the fastener head, you will never be able to get it in because the jaws are in their most open position. If you push too hard, the nail will break or damage the parts.

After inserting the fastener into the hole, push the pin in until the panel of the part to be joined is closely aligned with the fastener head. Once you get used to it, it's very easy to put on and take off, but there may be cases where fasteners of slightly different thicknesses and lengths are mixed together, so set them correctly when restoring.

There is also a set procedure for reinstalling a quick fastener that has been removed. Push the pinout of the zipper head by pushing it out from the backside when you remove it. This is how it works. In this way, the jaws of the fastener body are squeezed. As you can clearly see, the slightest stroke of the pin will cause a slight but definite change in the diameter of the jaws.

Once the fastener is inserted into the hole with the pin protruding, push the pin in until it becomes two-lined, and the claw will open and lock. It's a strange sensation to think that just that is all it takes to connect the panels together, but the flexibility and resilience of the resin is the lifeblood of the quick fastener. That's why it's important to note that if the resin loses its tenacity over time, the nails can easily crack. It is safe to consider fasteners that have been worn on and off several times or have been used for a long period of time as consumable and replace them.

The quick fastener shown here is a rivet type, but with the screw type, there are Phillips and Minus grooves cut into the head of the pin, just like a metal screw, and by turning it counterclockwise to loosen it, the jaws on the fastener body are squeezed out.

In addition to the standard bolt and nut, there are a variety of ways to fasten plastic panels together, such as using rubber well nuts, hanging nails, inserting pins into rubber grommets, and using quick fasteners. The newer the model, the more the quick fasteners are utilized, so it is recommended that you learn how to attach and remove them.

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