Bicycle rear hub: device, maintenance, disassembly and assembly
One of the main parts of bicycles is the hub, the quality of which determines the main characteristic. “rolling”. There are a huge number of them, but the rear hub of the bicycle causes great difficulty, the device of which is quite complex.
Installation of bearings
Easier to install from the ratchet side.
How are the bushings of a bicycle lubricated? This question is relevant for many cyclists. When assembling the rear hub of a bicycle, it is recommended to use grease for bearings, such as Litol and SHRUS. For gears in the ratchet and dogs, a liquid lubricant is more suitable (you can mix it with a thick one).
It is imperative to remove old grease before application using WD 40 or kerosene. Apply a thin layer of fresh lubricant after the solvent has dried. If this is not taken into account, then excess lubricant while driving will lead to contamination, which will shorten the life of the part.
What you need to know to remove the combination ring from the bearing?
This will require special tools. Using a system of levers corresponding to the size of the sockets, the ring is unscrewed clockwise. Having coped with this work, you can proceed to the next step. removing the bearings.
Having done this, they are lubricated so that they sit well in place. All the washers (there are at least three of them) will need to be removed from the core of the removed rear bushing without damaging it. They need to be wiped and kept in the same order.
They should be reinstalled if there are no major problems. If you notice problems with gear shifting, you can try to remove the thinnest of them, collect and check if the problem has disappeared.
If not, replace the washer and remove the thicker one. If you can only achieve acceptable load with the thickest washer, the rear bushing may be worn out and need to be replaced.
Before reassembling, make sure that the bearings are in the correct races from which they were removed. They must be installed in their places, without rearranging them to the other side of the wheel, since the gaps formed during wear are different.
Sufficiently small bearings of cassette bushings are easily lost, but it is not recommended to use a magnet to search for them, since, being magnetized, they will attract iron particles, which will lead to their rapid wear.
At the stage of cleaning them, they are wrapped in a rag to remove excess grease. Then the process is repeated by moistening a clean cloth with solvent.
If defects or obvious signs of wear are found, replace with a new one.
How i removed a freewheel cog easy without any special tools
Depending on the manufacturing process, the bushings are divided into:
- cast. the most durable.
The latter are of great weight. They are placed on wheels with radially spaced spokes to increase radial loads.
How to Remove Freewheel Without Any Special Tools
In order to reduce weight on bicycles belonging to the high class, rear hubs with hollow axles of a larger diameter and increased rigidity are installed.
On road bridges and mountain hikes, they are installed with collapsible bearings, which are distinguished by their increased efficiency. It is not difficult to install them, and adjustment is not required.
The most common today are bicycle rear hubs equipped with tapered angular contact rolling bearings.
Disassembling the rear hub of a speed bike to adjust is not as difficult as it sounds. In order for these parts to last longer, they must be lubricated, cleaned, adjusted, and bearings replaced in a timely manner.
In the price segment, the leading position belongs to the manufacturer Shimano, whose parts are distinguished by the fact that, thanks to thrust radial rolling bearings, the function of their adjustment and repair becomes available.
Their hallmark is the ability to attach spokes without flanges. The best quality, according to a large number of cyclists, is in this Deore LX brand. Alivio is considered a good option.
Noteworthy are the products of the Taiwanese company Novatec, which are confidently conquering the market.
In the picture provided in the section “How to disassemble and assemble the rear hub?” parts that cannot be removed are marked in red. If you damage them, you will have to change.
In this step, the rear hub is completely disassembled. Remains to clean with a wire disc brush the threads of the set screw and other screw connections to prevent galling after the part is in place.
Next, check for cracks and chips all the components, including the pawls, which, in order to remove, must be pulled back and the retaining spring ring raised.
If faulty components are found, they are replaced with new ones. When assembling, the dogs are installed in the correct direction and place. Otherwise, the cassette rear hub will not rotate.
While assembling the core, lubricant and anti-seize agent are applied to the threads of the set screw. In the same way that was used to remove the retaining ring, fix the core, applying a force of 3-7 kgf.
Grease is applied to the bearing bore, which works like glue, holding them in place while the rest of the parts are being installed. Now, having lubricated the ratchet ring, they are placed inside the shell.
When one side of the rear sleeve is assembled, the core is carefully placed in the cage, secured, washers are installed, being very careful, insert the bearings into the cages so that they do not deform. On free running, check the work of the part.
To screw in the combination ring, rotate the rear bushing shell counterclockwise to ensure that the bearings are installed correctly. If everything is assembled correctly, the ring is tightened with force.
How to remove rear sprockets from a bike
The bike drivetrain requires periodic maintenance. The most common problems are chain wear and failure of one or more sprockets on the cassette. Wear is also true for a single-speed one, the only difference is that the chain and the star itself are designed for longer operation.
The worn out part of the transmission negatively affects its entire operation, so the used sprocket will need to be replaced. Especially this problem pops up on asterisks that are used too often, which, in principle, is logical. Before changing, it is necessary to remove the worn-out sprocket from the rear wheel, which we will talk about further.
Bicycle sprocket care
Needless to say, all mechanisms require maintenance, otherwise they will quickly fail. If you clean the transmission of dirt as it gets dirty, it will significantly extend the life of the part.
You can clean the bike structure according to the following principle:
- Release the brake and remove the rear wheel;
- Inspect the inner cassette for dirt. If the dirt is strong, then without removing it will not be possible to clean, in the case when the dirt is minimal, then you can clean it directly on the bike;
- Use coarse-bristled brushes for cleaning, but they should be small enough to get into hard-to-reach areas. An old toothbrush that is not planned to be used for its intended purpose is suitable for such cleaning;
- Initially, a rag should be dipped in kerosene and only then start removing dirt from the sprocket;
- After cleaning, apply grease to the brush and wipe over the teeth. Then install back.
In order not to change the asterisks, you should constantly carry out proper care and diagnostics. Spending once a month a few minutes of your time to lubricate the sprockets, you can protect yourself not only from large costs, but also wasting extra time.
Therefore, it is much easier to take care of in a timely manner than to repair your bike, especially if you use it often enough.
If a breakdown still happened, you should not be upset, but make every effort to fix it yourself.
How to remove a rear sprocket on a bike
How to change sprockets on a bike?
The bicycle is becoming more and more popular nowadays. This is due either to paid parking and the high cost of gasoline, or to the currently fashionable healthy lifestyle.
But almost everyone loves to ride a bicycle, but not everyone knows how to properly care for it. Naturally, over time, parts fail and they should be replaced with new ones or serviced.
Within the framework of this article, we will talk about bicycle sprockets and how you can disassemble and care for them.
How to remove sprockets from the rear wheel of a bicycle?
It is absolutely not difficult to disassemble the device for replacement, but you should be careful and have a couple of free hours in stock.
In some situations, the disassembler initially spends 15 minutes, and another person without the necessary skills can handle it in 1-2 hours.
That is why it is difficult to answer the question of how much time can be spent on a laborious process. In most, all stars have the same parsing method, since they have almost the same structure.
Helpful hints for parsing:
- How the parts are removed, in this order they should be installed. This advice will help from confusion and waste of extra time that can be spent remembering where a certain detail came from;
- After parsing, every detail needs to be inspected, perhaps it does not require replacement, but a banal cleaning is simply necessary.
Bicycle sprocket design
The mechanism externally has several stars of different sizes, which are fixed with a bushing. After that, everything is connected with a lock nut.
- The usual version is that the stars are connected to each other by a plastic spacer;
- Spider cassette. cassettes made in the form of stars, fixed on an aluminum frame;
- On several spiders. devices that have a high cost and are usually installed on professional and expensive models. The appearance has 2 spiders, which are connected by sets of stars;
- X-Dome is a monolithic system that connects the drum to the lid on the opposite side;
- OpenGlide. Most Relevant for Road Bikes.
Dismantling the transmission cassette
The rear of the transmission is not too difficult to disassemble, all that is needed is time and a few tools: a cassette puller, a whip and wrenches (open-end. for removing a wheel and an adjustable. for a cassette).
The first thing to do is to free the bike from the rear wheel. Using a wrench, the nuts are unscrewed, and the chain is dropped from the rear sprockets. On a mountain bike, it is usually a matter of a second to remove and put on the wheel, thanks to the eccentric fastening.
The removable device is installed on the slotted nut of the cassette. A whip. a small flat “knife” with a fragment of a chain. is needed to keep the cassette from turning. With the help of an adjustable wrench, we rotate the puller, we direct the whip in the opposite direction, or, more simply, we hold it with a large star of the system.
To unscrew the nut, you will need to sweat a little, and not only in the first stage. With the same good effort, the stars will need to be returned to their place. Once the nut has folded, the cassette can be safely unhooked from the wheel. Now it remains to examine it and determine which star needs to be pulled out.
Some of the outer small sprockets can be removed immediately when removing the cassette. They should be cleaned and inspected for wear. The same is done with the main sprockets: it is determined how much they are worn out and which ones are the most.
Disassembly process of transmission cassette
Some theory beforehand. On the rear wheel there can be two variants of parts related to gear shifting.
- Transmission cassette. This product features modernity and innovative spline mountings that attach to the hub axle.
- Ratchet. A somewhat outdated model typical of inexpensive speed bikes. The set contains no more than seven gears. As for the mount, it has a thread with external installation parameters.
Let’s focus on the ratchet right away. Changing the rear sprocket on a ratchet bike is not possible. Only change the entire component completely.
Therefore, the topic of the article will be a problem describing a situation when a bicycle cassette star needs to be replaced. As for the set of stars in the transmission, up to 11 pieces are possible, depending on the bike model.
So how do you change the rear
sprocket on a speed bike? Consider the algorithm of actions.
- Take the bicycle wrench for the rear wheel and dismantle it. We sequentially unclench the levers and loosen the fixing of the nut.
- Now it is the turn for the axle nuts. Using another key, we turn off the mount.
- The next step involves unscrewing the bearing cone and pulling it out.
- We take out the axis with all the elements.
- We take a special tool. a cassette remover. We insert it into the slots.
- The whip is placed on the largest sprocket. We make rotational movements clockwise.
- At the same time, using an adjustable wrench, the puller rotates in the opposite direction.
The preliminary stage is over. Such simple actions are possible in ordinary home conditions. We emphasize that if more than one star is worn out, but several, then it is better to replace the entire cassette at once. This option is also desirable when the largest star is damaged.
And one more recommendation. We put all small parts, washers and nuts in a certain place, so that later we do not search all over the room