It is promised that all bearings removed from the wheel hub should be replaced with new parts. But, oh no! I forgot to buy new parts! In some cases, what an emergency, you have to reuse it. In such cases, complete cleaning is where it all begins.
Motorcycles are called "two-wheeled vehicles", and the reason they are called so is because of the presence of front and rear wheels. The axle shaft receives the spinning wheel. The wheels are spinning around the axle shaft, and the axle shaft (axle shaft) is held by the bearings. These parts are called "bearings". The bearings press-fitted into the wheel hub are sometimes knocked out or pulled out at the time of removal, so they must be replaced with new parts when the wheel is reassembled.
However, they ordered parts by mistake or thought they had them in stock, but they didn't. I'm a Do-it-Yourself Sunday mechanic and I want to get on my motorcycle tomorrow! What a case, right? Here's the least you can do when you have no choice but to restore and reuse it.
In general, the "wheel hub construction" looks like this
The parts inside the wheel hub of the disc brake model are arranged roughly like this. In this illustration, there is no dust seal on the outside of the right side hub bearing. In the case of competition models, in order to reduce friction loss (to reduce frictional losses), the dust seal is sometimes not installed to prevent dust from entering the motorcycle, but instead relies on the seal bearing.
Parts that were built into the disassembled wheel hub. This is the layout order. The hub bearing is a deep groove ball bearing sealed on both sides. You should know that the center collar between the bearings is very important.
Notice the distance collar on both edges!
When you replace a bearing because of a rattling or rumbling noise in the wheel, pay attention to the condition of the end surface of the "distance collar". There may be burrs on the edges, or the end-face may be shiny and worn. That means that the collar end-face is worn. When you notice a problem due to noise or rattling and replace the bearing, it is a good rule to replace the distance collar with a new part as well as the bearing.
Reuse of bearings is strictly prohibited. If you have no choice, use the best you can.
Sometimes there is a gap between the "ideal and reality. Even if you can't bridge that gap with maintenance, sometimes the best you can do is to overcome it.
Prepare a thin pick tool and remove the seal by hooking the tip of the tool on the inner ring side of the seal. Pour fuel or kerosene into the container, soak it thoroughly and then blow out the old grease. Use an air gun while pressing down with a rag, but in this case, fix the inner and outer rings with your fingertips to prevent the bearing from being rotated by the force of the air.
High-performance grease is applied to the bearing and the grease is pressed into the deep groove of the ball bearing by pressing the grease into the palm of the hand. Here, we used a high-performance urea grease that is resistant to heat and moisture, rather than a calcium-based grease that is water-sensitive and easily emulsified.
Once the grease is tapped in from both sides, snap the removed bearing seal to the outer ring. For both contact and non-contact types, the seal holder is on the outer ring. Use your fingertips to compensate for any bends in the seal as much as possible.
Thoroughly remove the dirt from the hub side bearing holder when you press-fit the bearing back into the wheel hub. In the case of a hub that has a circlip on the side of the bearing, press in the bearing from the side that does not have the circlip groove, and then press in the circlip side. Then press in the bearing side from the side without the circlip groove, and set the circlip.
POINT
- Point 1 - In principle, do not reuse wheel hub bearings that have been removed.
- Point 2 - Thoroughly clean and grease up your bearings before you reuse them in an emergency situation. After cleaning, make sure there is no backlash.
- Point 3 - Dispose of the bearings that were removed due to rattling or noise problems immediately. Replace them with new ones. At this time, replace the distance collars with new ones too.
Removed wheel bearings are the parts you don't want to reuse. If it was pulled out by hitting it, even more so.
However, there are times when you need to reuse bearings that should have been discarded. Sometimes you find out during the process that you didn't have the bearings you thought you had bought, when in fact you didn't have them on hand. And then there were times when I realized that I'd have to recycle the bearings I thought I'd bought but didn't have them on hand, and I had to go to ride tomorrow. When you have no choice but to reuse such a bearing, you should not just return it to its original state (restore it), but restore it after maintenance for the "best of its current state".
Generally, wheel bearings use "deep groove ball bearings" (ball bearings). Some foreign motorcycles use tapered roller bearings and use shims to adjust lateral pressure for smoother rotation and bearing rigidity. Most Japanese motorcycles use ball bearings, and many manufacturers use single-sealed bearings to reduce costs.
Here, the non-contact type double-sealed bearing is used as an example, and the seal can be removed again without difficulty by using the tapered pick-up tool.
Soak the removed bearing in kerosene or gasoline to clean the grease inside. Next, pinch the inner and outer rings of the bearing at the same time to stop them from rotating, and blow the grease off. At this point, do not use air pressure to turn the bearing. It can cause damage to the bearing groove. After cleaning air blowing, let's fill it up with high-performance urea grease, set both seals and then assemble and restore it to the wheel hub.
If you hear rattling or rumbling noises, or if the wheel has rattled in the bearing when you shake it, you should replace it with a new bearing, no questions asked. When you do this, you should also replace the distance collars between the left and right bearings with new ones. This is because both sides of the distance collars are worn out due to bearing damage. It's not uncommon for this to happen, and it's not uncommon for a new bearing to be replaced with a new one, only to have the bearing fail again shortly afterward.
Even if there are no trouble factors, be sure to thoroughly inspect the condition of the distance collars when you remove the wheel bearings.
