How to Remove a Sprocket Block on a Bicycle

Replacing the cassette on a bicycle

Experienced cyclists know well that a set of rear sprockets of an open multi-speed (sports) bike transmission, the so-called cassette, is actually a consumable unit. Indeed, with intensive high-speed skiing, the teeth of the cassette sprockets wear out quite quickly, and approximately every 1000. 2000 km of run there is a need to replace it with a new one.

Then how do you replace the cassette on your bike? The first and best option for replacing the cassette on a bicycle is to “take” your bike to a specialized bike workshop, where this operation will be performed as professionally as possible. But, unfortunately, a good professional bicycle service in Ukraine is available only to residents of regional centers, at most, large cities. Also, many avid cyclists and their teams practice long-term out-of-town “rides”, “move”, during which serious malfunctions of bicycles are frequent, incl. and damage to the bike transmission cassette. Therefore, any “decent” cycling enthusiast simply needs to have the knowledge and skills to remove the stars from the rear wheel on their own.

What tools will be needed?

To remove a bicycle cassette yourself, it is imperative that you have the following list of tools and accessories in your home workshop or in the set of portable spare parts and accessories:

  • bicycle “whip” in the form of a segment of a bicycle chain attached to a handle-lever;
  • 12-slot end puller (or one-piece key-puller) of the cassette retaining ring;
  • if there is only one end puller, then you will also need a 24mm or 27mm spanner (open-end, box), depending on the size of the hex nut on the spline puller.

Bicycle rear sprocket cassette removal procedure

How do I remove the stars from the rear wheel? By and large, for this purpose, you just need to unscrew the cassette retaining ring, which holds together all the parts of the mechanism. This locking ring has a classic right-hand thread, you can recognize it by the Lock inscription on its surface.

But the trick is that to unscrew this locking ring, you must have a special device (special key). 12 spline puller. In this case, it is necessary to simultaneously keep the cassette sprockets from turning on the bearing. Best suited for this purpose is a special “cunning” device. a bicycle “whip”.

The procedure for dismantling a multi-star cassette:

  • Perform operations to remove the rear bicycle wheel: install the bicycle on the handlebar and saddle, wheels up; unscrew the tightening nuts on the wheel axle (or loosen the eccentric fasteners); remove the chain from the cassette sprockets; remove the wheel from the dropouts, put it on a horizontal platform with the cassette up.
  • Throw a piece of the bicycle whip chain over the large star of the cassette so that the handle of the whip forms a lever that is easy to grip, applying force on the cassette clockwise.
  • Insert the puller into the slots of the cassette retaining ring.
  • Grasp the hex of the stripper (24mm or 27mm) with a wrench.
  • Applying opposite forces on the handle of the wrench and on the handle of the whip, it is necessary to turn the retaining ring along the thread. Most likely, you will have to apply considerable effort, as the retaining ring is usually dirty, “stuck”, and just too tight. Since significant efforts are applied when unscrewing the retaining ring, the use of various handicraft devices and non-specialized universal tools (screwdrivers, pliers, chisels, etc.) for this purpose should be avoided.
  • Unscrew the retaining ring completely, then pull up the cassette and remove it from the splines of the drum (ratchet) of the wheel hub. If the cassette is assembled on a “spider”, it will pull together as a single unit. If the cassette is assembled on pins, without a “spider”, then, most likely, each sprocket and spacer washer will be removed separately.

Fitting the bike cassette to the bike

  • Install the cassette assembly on the “spider” into the splines of the wheel hub drum. A cassette without a “spider” will have to be recruited vertically on the drum, not forgetting to lay washer-spacers between the sprockets.
  • Place a retaining ring on the cassette and the drum, screw it in manually if possible without additional tools.
  • Using a whip to block the largest sprocket of the cassette, and a puller and a wrench to tighten the retaining ring, screw it in until it stops.
  • Install the rear wheel assembly on the bike, put the bike chain on the gear wheels (stars) of the transmission.

Replacing the bike ratchet

It happens that some older sports bikes still have a previous generation rear sprocket assembly called a ratchet. The multi-star ratchet differs from the more modern cassette in that it is screwed (right-hand thread) onto the wheel hub as a whole, with its entire body. Therefore, when dismantling the ratchet, there is no need to keep its sprocket from turning. It is enough to hold the wheel rim with a hand or other fixation, which is incomparably easier.

A special spline puller is also required to remove the multi-star ratchet from the rear wheel. It is similar but not compatible with the cassette remover. The extractor key must be inserted into the corresponding slots on the ratchet cover and grab the hexagon with a wrench. Applying a force on the wrench counterclockwise, and holding the wheel rim with the other hand from turning, it is necessary to turn the ratchet body along the thread. As with the cassette, this can be tricky and will likely require quite a lot of effort.

Again, the question arises, how to remove the ratchet without a key (puller)? Should again disappoint enthusiasts of a non-standard approach that this technique will most likely fail. In the name of keeping your bike’s drivetrain intact, we strongly recommend purchasing and carrying a dedicated ratchet splined puller. In this case, the operation to dismantle and reassemble it will have a much better chance of success.

How to replace bike cassette sprockets. Disassembly process of transmission cassette

Some theory beforehand. On the rear wheel there can be two variants of parts associated with 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. Rear sprocket cannot be replaced

Only change the entire component completely.

Therefore, the topic of the article will be a problem describing a situation when a replacement cassette is needed. As for the set of stars in the transmission, up to 11 pieces are possible, depending on the bike model.

Ratchet and cassette elements

So how do you change the rear sprocket on a speed bike? Consider the algorithm of actions.

  • Take the bicycle key 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, 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.

Sleeve recessing process.

  • 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, it is better to replace the entire cassette at once. This option is also desirable if 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

Types of cassettes

The number of stars in the system ranges from seven to ten. The material for the manufacture of the structure can be steel, titanium or aluminum alloys. Steel products, chrome-plated or coated with another material that prevents corrosion, are more widespread. So, bike cassettes differ in the following characteristics:

  • design,
  • material,
  • number, range of stars,
  • bike type compatibility.

The number of possible speeds available to a cyclist depends on the number of gear stars. Appropriate cassettes are selected according to the type of bike. For example, for mountain bikes, the number of star range should be greater than that of a city bike. Depending on the selected mechanism, its price also varies.

Variations in cassette types are due to different fastening of the stars on the retaining ring and to each other. The system can be disassembled, or it can be integral.

  • Collapsible cassettes. Such a mechanism can be disassembled completely into separate elements.
  • Fastened into a non-separable knot with a Spider connection, one or more. Spiders can hold together several groups of stars; when worn, a separate part can be changed. And if the system is connected by one fastener, the whole mechanism will have to be changed.
  • One-piece construction. The cone block is made in one piece, cannot be disassembled.
  • Block is made in the form of a single piece of medium stars, fastened between the large and small stars.

Dismountable bicycle cassette

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 mount.

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.

Removing the rear wheel sprockets

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 detached from the wheel. Now it remains to examine it and determine which star needs to be pulled.

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.

Removing the sprocket from the rear wheel of a bicycle

Disassembling a wheel to replace parts is not difficult at all. You will need some free time and tools like a pair of wrenches, a cassette remover and a whip. In most cases, all stars are collected in the same way on mountain bikes, since they have a standard structure.

  • First you need to turn the bike upside down to a stable position.
  • Now you need to remove the wheel. To do this, use the key. Throw the chain to the side. On modern models of the sports unit, the wheel is removed even easier (thanks to the eccentric).
  • Now you can start parsing. Use a whip to keep the cassette from spinning, and install a puller on the cassette nut. Next, we work with the key, here you have to work hard to disassemble the cassette. If during unwinding you hear a characteristic crackle, do not be alarmed! This happens if the sprocket size is small. After the nut has been unscrewed, you will need to unscrew it by hand with a little effort. Now remove the cassette and inspect everything for wear.
  • Do not forget to fold the parts in the correct sequence during disassembly, otherwise you may have problems during assembly.
  • The last thing to do is to remove the protective plastic ring.
  • After the parts are removed, it is necessary to inspect and lubricate the parts that need lubrication.
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How to choose the right cassette for your bike

The bike is sold with a cassette, but periodically there is a need to replace this unit. This is sometimes due to wear on the sprockets, which wear off the teeth, chain slippage can signal that it is time to change the cassette. But sometimes the replacement of the cassette is dictated by the fact that the cyclist is heading to another region with a different relief and type of soil, plans to master a different riding style.

In the first case, you can safely choose a cassette with a marking similar to the old one, with the same number of speeds and a range of stars, and if you want to experiment, test the products of another manufacturer, another material. In the second case, a change in the number and range of stars is justified.

The first thing to look out for is the bike type, mountain or road bike, and the attachment system. Which cassettes are suitable for which bikes, described above

You also need to take into account your financial capabilities, but remember that expensive cassettes are stronger and more durable. If minimizing the weight of the bike is not a priority, it is not worth spending money on titanium and aluminum cassettes, it is better to get the more expensive steel one. Here the price is directly proportional to the resource.

From a constructive point of view, it is worth paying attention to cassettes on several spiders, they are lighter than conventional collapsible ones, are less prone to contamination and allow you to change individual units, and not the entire cassette. Thus, although such a cassette will cost more, it should last longer.

The more styles a person uses, the more difficult the terrain on the route he takes, the more stars it is more expedient to have in the cassette. stars mean more range, smoother gear changes. For flat terrain, fewer stars are sufficient; for rugged terrain, more are needed. The number of stars must match the chain, narrow chains are for cassettes with a large number of stars, 9-11, if the chain is wide, there should be fewer stars.

The 11-star cassette allows virtually no use of the front derailleur. The optimal number of stars is a very individual criterion, and often only through experience, by changing several cassettes, it is possible to establish which configuration provides the most comfortable ride. Experienced cyclists generally collect cassettes from individual stars for their needs and for a specific trip.

The required sprocket range depends on the riding style. If it is supposed to ride on good, hard ground, asphalt, without elevation differences, steep climbs, the number of teeth on a small sprocket is not important, but on a large one, a fairly small amount, range 11-21, if on the route occasionally there may be small slides, range 11 is preferable.23. If you have to travel on loose, wet soil, sand, snow, and / or alternation of steep, but short climbs (“sticks”) with shallow, but protracted (“pulls”), you need more teeth on a large star, range 12 is suitable.36. The steeper the mountains, the more range you need. And also, the more massive the cyclist, the more teeth on the big chainring will be needed, all other things being equal.

In short, when choosing a cassette, you need to be guided by your own experience, feelings, riding style and the purpose of the trip. If you have little experience, it is better to consult other cyclists, sales consultants do not always know all the nuances.

How to unbuckle a bicycle wheel

Bicycle wheel disassembly

We carry out the process of removing the wheel. How to do it mentioned above.

Now you need to lower the wheel, because without this, you will not be able to remove the camera. We find the cap that is screwed onto the tire nipple, turn it over in the opposite direction and insert it into the nipple and start twisting.

If you do everything correctly, you will hear the sound characteristic of the descent wheel, the hiss of air bleeding through the opening.

After the air is deflated, take the beads or screwdrivers

With the help of one we pick up the tire located near the nipple, and we drag it out, the screwdriver itself, attention, we leave inside. Do not be distracted, because you can break through the camera, be especially careful

Now we take the second bead (screwdriver), and a little further from the nipple we pry the tire. Pull it out gently. So, step by step, making movements in a circle, you will remove the tire, be it a rim or a disc.

So, step by step

  • The rim brake opens, if any
  • We remove the damaged wheel, having previously unbuttoned and unscrewed the eccentric. Make sure that the unscrewed nut and the removed spring are not lost when falling
  • We lower the pressure in the chamber to the minimum
  • We stick a bead between the tire and the rim located on the side of the wheel. Side must be opposite to nipple
  • We release the border towards the center of the wheel and hook it onto the spoke, do not forget to do this, because this is a common mistake of novice cyclists
  • After 5-10 centimeters, repeat, but with a different border
  • Remove evenly, with both hands, finish near the nipple
  • Removing the camera
  • We remove the second bead of the tire. Do not forget to look and feel the tire, if there is any sharp object or pebble left there, which will ruin the next tire

Removing the ratchet (for hubs with screwed-on ratchet)

On such bushings, the cassette is removed together with the ratchet, therefore, when adjusting the bearings or replacing the spokes, it is not necessary to disassemble the cassette. This only needs to be done to replace the sprockets themselves.

To change the spoke on the right side of the rear wheel or to change the grease in the bearing, the cassette can be removed with the ratchet without touching the hub axle. The inner surface of such a ratchet has slots into which an appropriate puller must be inserted. The sprocket block rotates here on the ratchet body. The body itself is screwed onto the sleeve and the puller is inserted into the body.

We insert the puller into the slots on the ratchet, and turn it off with an adjustable or open-end wrench. Unscrewing may require considerable force. We recommend using a gas wrench or a long-handled wrench of 24. The ratchet thread is left, unscrewed clockwise (against the freewheel of the ratchet).

Then we remove the cassette together with the ratchet and the protective plastic ring.

If you are going to replace a wheel, leaving the old ratchet, then buy a wheel with a hub just for the ratchet. With such a hub, you will see only the axle without the hub drum.

Removing the cassette

You have to remove the cassette, firstly, to adjust the bearings of the rear hub (in principle, you can not remove it, but with the cassette removed, it is more convenient to adjust the hub), or to replace the sprockets themselves. If during a trip you have to replace the rear wheel spoke on the right side, then the cassette will also need to be removed.

The cassette is tightened to the ratchet with a slotted nut. In order to unscrew this nut, you need a special tool. a cassette puller. And in order to hold the cassette (you have to unscrew the cassette in the direction of free rotation of the rear wheel. counterclockwise), you need a whip.

The cassette sprockets are put on the ratchet body and tightened with a wide nut of a special shape. A bushing with a built-in ratchet mechanism is used. Plastic washers are inserted between the sprockets.

When disassembling a cassette, it is necessary to take into account that not only the order of the asterisks is important, but also their orientation relative to each other. Washers can also differ in diameter and thickness, so it makes sense to carefully lay out all the removed parts in a row.

To unscrew the nut, you will need a special spline wrench, and to keep the cassette from turning, you need a whip, because the direction of rotation of the nut when unscrewing coincides with the direction of free rotation of the ratchet.

We put the whip chain on the largest sprocket of the cassette. We turn off the nut with a wrench, holding the cassette with a whip. If you don’t have a whip, you can use the old chain instead, securing it in some way so that it holds the spider. You can also use an old thicker and larger rag. We fold it in several layers and throw it on the spider, holding it with our hands. The spider is held with its entire palm through a rag and turns with a key.

Remove the nut. Then we remove all the sprockets and washers from the ratchet body, observing their order. If necessary, remove the bushing drum from the axle.

Shimano Cassettes & Ratchets

It is necessary to remove the cassette, firstly, to adjust the bearings of the rear hub or to replace the sprockets themselves. If during a trip you have to replace the rear wheel spoke on the right side, then the cassette will also need to be removed.

In fact, there are no fundamental differences from the method described above.

Removing and installing a star on cassettes

Unlike ratchets, in this system the stars can be changed individually. All that is needed is to remove the old part and put a new one in its place. Special rivets and small spacers are located between the stars, which allow them to hold a fixed position and facilitate the installation of the cassette itself. It is very easy to screw the desired star from the device, the main thing is not to get confused in the sequence, especially on large cassettes of high-speed mountain bikes.

Sometimes on cassettes “spiders” can be found. rigidly fixed areas of several stars. Here you will have to replace the entire set, on which one of the stars is badly worn out. True, this only applies to large transmission rear wheel sprockets.

When replacing a single chainring, you may encounter the problem of the difficulty of switching the chain to it. This is due to the fact that the chain already has wear compared to the new sprocket. And if this is not so noticeable with one detail, then several new stars will immediately bring a noticeable dissonance to the operation of the transmission. That is why it is advisable to change the cassette simultaneously with the chain.

Insert cassette

Replacing the cassette consists in simply lifting it up from the wide splines of the ratchet bushing and pushing a new set of stars back along the grooves in them.

Reinstalling the cassette is as easy as removing it. This is essentially the reverse operation. The sprockets should fit snugly on the ratchet splines. It must be remembered that one of the slots is different in width from the others. Be careful. Be careful not to damage the spline flange when putting on the last two small sprockets. Knowing this, it is enough just to put the cassette body (rings and stars) on the ratchet and finally screw the clamping nut along the thread.

Be careful. Observe the order of installation of the sprockets and spacer rings, which are simply typed onto the splines of the ratchet sleeve one by one. Each spacer ring has two small pins that must fit exactly into the corresponding holes in the sprockets. If this is not done, the sprockets near the ring will be placed too far apart, which will ruin the precise operation of the speed switch.

You need to tighten the end nut firmly with the same puller and a large wrench. We don’t want the cassette to spin on the road, so it’s a good idea to place the wheel upright and push down on the key lever firmly. But don’t push with your foot! It is recommended to apply a force equal to 21.7–36.2 N ∙ m (about 3 kgf ∙ m). The nut is tightened clockwise, the ratchet is locked in this direction, so you do not need a chain wrench to install the cassette.

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The lubricant should be used like a tube-type bicycle grease or any other non-lithium, dust-repellent oil.

After assembling the cassette, make sure that the sprockets do not wobble relative to each other. It is also a good idea to make sure that the distance between them is the same. If everything is correct then put the wheel on and go for a drive!

How to remove sprockets from a bicycle wheel. sequence of actions

A bicycle cassette with sprockets differs from a ratchet in that individual sprockets can be replaced individually. All that needs to be done is to remove the worn part and replace it with a new one. The space between the individual stars on the wheel is filled with spacers and rivets, which make dismantling and mounting easier

It is only important not to confuse the sequence. This is especially true for multi-speed mountain models

It happens that cassettes are equipped with “spiders”. This is a design where several sprockets are rigidly fixed. In this case, if any of the parts is badly worn out, you will have to replace the entire “spider”.

Replacing single sprockets can cause chain switching difficulties is great. This is because the chain is sufficiently worn out in relation to new sprockets. For this reason, it is advisable to replace the chain and cassette at the same time.

Removing the bike cassette

We take the second important tool, and an adjustable wrench. We put the puller on the wheel and install the toothy garbage in the nut. Well, your favorite adjustable wrench is there.

Then press down on both sides.

It turns out this is the kind of thing. or rather, nothing happens. I took a stick from some pressed cardboard, which safely showed me its guts. The next stick was from dried birch.

We put it on the wheel again.

We press from both sides down. We hear the nut micro-clicks (there is a ribbed surface, and when you tighten the nut, it is securely fixed).

We throw off the cassette from the hub, rinse and inspect each asterisk. If the output for any of the asterisks is quite high, then it is better to change this asterisk. Most often, “favorite show” stars are generated. Usually medium, since there is the lightest pedaling effort. In my case, the sprockets are in pretty good condition, and after troubleshooting, I decided to reassemble them in the same form, without replacement.

How to remove a sprocket cassette without a puller?

Sometimes, instead of the first tool with a chain, people advise to “throw a rag over the stars” and turn the nut with a puller. I’ll be honest. I tried it. The rag turned into rags from sharp bicycle teeth.

The second option for replacing the cassette retainer is to take the old chain, put it on one end of the cassette, and put the other end on the rim of the tire wheel. Fix there and turn the nut with a puller. As a result, the chain thrown over the tire pushed the tire to the rim and crumpled the last.

The third option came by itself, when I studied in detail the device of the retainer. We again need an old chain, a stick, 4 screws and a screwdriver. It is better not to use nails. they are ripped out of the stick with a bang.

Putting it all together like a photo of a Shimano professional cassette remover.

Internally device

A bicycle cassette is a pyramid made up of stars of different sizes, which is a high-speed chain drive unit. The sprockets are separated by an equal distance between themselves by rings or, in some expensive models, by an internal spider frame. Together, all these parts form the body of the device.

The cassette is mounted on the bike to the ratchet drum along the slots. The ratchet itself in a cylindrical body is attached to the wheel hub with similar hooks. It is the separate cylindrical mechanism on the rear wheel that bursts during free roll and engages tightly during pedaling. In the cassette, there are no dogs or a gear.

The cassette body is finally fixed to the rear wheel by an external clamping nut screwed into the internal ratchet. She and the smallest sprocket have teeth on their mating surfaces to prevent unwinding while riding.

Tool for work

  • Ratchet puller.
  • A larger adjustable wrench or a wrench, usually 27 mm, but note that there are pullers with 24 mm edges. It will be more convenient to use a box or socket wrench, since it will be possible to press on it with the maximum possible force, without fear that it will jump off the edges of the puller.
  • Open-end wrench 14 or 15 mm for unwinding the sleeve.
  • Thick lint-free rag.
  • Thin center punch, if you need to disassemble the “nut”.
  • The hammer never hurts.
  • Non lithium grease. Thick oil generously packed inside the assembly can cause the dogs to stick. After that, the pedals often begin to scroll not only backward, but also forward.

Bicycle cassette and chain maintenance

Clean your bike cassette thoroughly at least twice a year. Be careful when cleaning around the hub. Do not hose down your bike or use a solvent as this can dissolve the oil in the bearings.

It would be nice to replace the chain as well when changing the cassette (chains wear out faster than cassettes, so you can change the chain twice before it is cassette’s turn). The cassette and chain must be compatible with each other. For example, if you have a 9-speed cassette, then you need a 9-speed chain.

Poor chain condition will wear out the teeth on the cassette sprockets. If you live near the beach, sand gets into the transmission system, or if you live in a damp climate, the chain can rust, so it is best to change the chain well in advance.

The final word on Singlespeed

Single speed bicycles have a retaining ring. Thanks to this, the star can be replaced in a few minutes. It is enough just to open this ring. Singlespeed enthusiasts claim that standard rings are flimsy and can break even if you don’t use them for replacement. There is a deal of truth in it. Therefore, it is worth constantly checking its condition and replacing it with a new one from time to time. Otherwise, the chain will simply dangle from side to side.

The assembly of this structure does not require any special skills. The ring is inserted without any effort, this is probably the main advantage of these models.

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Bicycle cassette maintenance and repair

Any part of a vehicle’s structure needs timely maintenance, and the cassette is no exception. The collapsible mechanism requires special care. Carefully inspect the removed cassette and all its parts, you may have to replace the system or change some of the worn out stars.

Cleaning the mechanism with a flat brush

It is necessary to clean all components of the mechanism with a flat brush. You can use a light detergent, but not a solvent, then wipe the parts dry. Lubricate the parts with a very thin layer of grease to prevent dirt from adhering to the next time you use the bike. The bicycle chain also needs to be cleaned of dirt, if necessary, replace it immediately, as it becomes unusable much faster than a cassette.

When replacing the chain, consider its compatibility with the chainring. If you had to change any details, they must fully correspond to the previous elements. A new cassette should be installed with the same gear ratio as the old mechanism, because all the transmission parts were not selected by chance.

Replacing the rear wheel sprockets on a bicycle

The assembly goes upside-down. By and large, to confuse the sides of the asterisk (which side to put out) tends to zero, since there are guides on the hub. And “backwards” to put asterisks is problematic. But, be careful. with a hammer, I think you can drive a star there

Then, lastly, install the nut. We twist it by hand until it stops. Here, you don’t have to use the chain on a stick, since the rotation will be in the other direction and the hub will not scroll. But I still recommend that you use your homemade tool.

The tightening torque of this nut should be quite strong. 40 Nm per meter (4 kilograms applied to a 1 meter long arm). And if you just tighten this nut with a wrench (without holding the chain), then there is every chance to unscrew the spokes from the wheel.

How do you remove the cassette from your bike?

Alex “On the Bike” Sidorov

Dish of the day: Ken Block has released a new video. Dzhimkhana. 9. My heart stops when I look at his tricks.

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How to install a cassette on a bike

First of all, make sure that the cassette assembly matches the unfolded / removed parts. To facilitate this process, the sprockets have grooves of different sizes (for each sprocket. individual), and the bushing has suitable splines. It is the correct alignment of the grooves and splines that all the sprockets will stand in a certain order.

There are some important things to keep in mind when installing the cassette on your bike:

  • Many cyclists lubricate the bushing surface before installing the part in question. However, experts believe this is wrong. after lubrication (until the entire cassette is assembled and installed), both dust and dirt will have time to get onto the applied lubricant, which ultimately leads to the need for maintenance, repair or replacement of elements.
  • Experienced cyclists lubricate the thread of the retaining ring before assembling the cassette. during subsequent disassembly it will be much easier to unscrew.
  • All sprockets must be worn alternately, but do not forget to put spacer rings between them. In some bike models, you can see not separate sprockets, but a single / one-piece assembly.
  • In many bicycles, to securely install the last sprocket, you need to lightly press it and only then you can screw the retaining ring.
  • After the locking ring is screwed in, first you need to check the correct installation of the cassette and only after that you can finally tighten it. Tightens the retaining ring clockwise.

Removing and installing the cassette is not difficult, because with a minimum set of tools and at least basic knowledge of the technical plan, all the work will take a little time, a maximum of 60 minutes. But even if such a process is to be carried out for the first time, you should not give up. the experience of removing and installing a cassette will certainly come in handy more than once. The fact is that experienced cyclists recommend carrying out such maintenance of the bicycle cassette at least once a year.

How to properly maintain your chain?

The chain wears out quite quickly, especially if it is not periodically cleaned and lubricated. It lengthens due to wear. You can check the condition of the chain by lifting it over the sprocket teeth. The new chain is lifted by 1-2 mm. But the chain needs to be changed when the stretch increases to 7 mm. When replacing the chain, you will have to change the rear hub sprockets at the same time.

If the chain is covered with normal road dirt, it can be easily washed off with a hose stream. But if the dirt is mixed with oil, use a clean cloth. Remove any dirt between the rear hub sprockets, wipe the carriage sprocket teeth. Next, spray the solvent between the chain links and clean them with a toothbrush. After cleaning the chain, line it with oil.

In good weather, the chain should be dry and clean, and during rain and frost it should be lubricated abundantly. Experts recommend changing the chain more often because it costs less than cassettes and systems. And the new chain will extend the life of the entire system. For mountain bikes, it is better to replace it every 2000 km, for hybrids and road bikes. after 3000-6000 km.

How to replace asterisks?

If your goal is not just to replace the outer sprocket. which can be easily done by removing the fasteners and threading it through the connecting rod. you will have to start by removing the drive sprockets. 2. Some high-quality connecting rod systems allow you to remove the sprocket bolts with regular hexagons or special Torx wrenches, but if your sprockets have regular bolts, you need either a special puller wrench that can be placed in the slotted groove of the sprocket nut or another hexagon (often 1 mm larger than the front) to keep the nut from turning. Special wrench. a puller keeps the sprocket nut immobile while unscrewing or tightening the bolt.

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Lock the nut and unscrew the bolts counterclockwise. Remove them carefully, they will come in handy for installing new stars. You can now remove the old chainrings or clean them thoroughly if you replace only the outer chainring to change the gear ratio.

Removing the cassette

After removing the rear wheel, remove the eccentric mount from the rear wheel. Then insert the snap ring removal tool into the cassette and twist until it is in the correct position (only one is provided). If your cassette does not fit a standard ring remover, contact your dealer or mechanic and they will find the model you need.

To press closer to the gears, remove the springs from the eccentric mount and reinsert it through the wheels and fixture.

If your bike has a thru axle that screws into the frame instead of a standard quick release mechanism, you can insert it through the ring remover to keep all cassette components in place when removing.

Place the wheel flat on the ground, stand behind it, take the collar in your left hand and hook it onto one of the large gear wheels of the cassette. Take an adjustable wrench in your right hand and fix the tool for removing the retaining ring with it. In this case, the gate will not allow the cassette to rotate during the dismantling of the ring.

Push the adjustable wrench and gate in opposite directions. As soon as you can loosen the ring, put the key with the collar aside and continue to unscrew by hand.

After removing the retaining ring, remove the cassette. If you plan to reuse any of its components, carry out the dismantling procedure very carefully.

How to replace cassettes on a bike?

All components of a bicycle drivetrain are subjected to enormous stress during the operation of the bike, so they need regular maintenance. If you see that the rear sprockets have become unusable, then you will need to replace the cassette on the bike, because the condition of both the chain and the chainring depends on its condition. If you do not service each of these parts separately in time, there is a risk that the repair of the entire transmission will immediately cost a pretty penny.

The process of removing the cassette itself is simple, but you need to know some of the subtleties, thanks to which the dismantling will take place without problems. There are several types of cassettes with a specific dismantling method. It is better to find out in advance for the future which one is installed with you.

Tools

To replace the cassette, you will need several keys, both special bicycle and regular keys:

  • Retaining ring puller;
  • “Whip”;
  • Adjustable wrench.

The first tool is needed in order to loosen the mechanism, the rest. to fix the structure. Next, we will consider in stages how the cassette is replaced on a bicycle.

How to remove the sprocket block from the rear wheel?

Turn the bike over, unscrew the eccentric, remove the chain and remove the wheel. You may need to open the brake pads if you have a rim brake system.

To start dismantling, you need to throw the key-whip chain over the largest sprocket: thanks to it, the system will be fixed and will not turn. After that, a ring-shaped puller is put on the wheel axle nut, an adjustable wrench is adjusted to its diameter. When you unscrew the nut, a fairly loud crack or crunch can be heard. do not be afraid of it, this is normal, this is due to the fact that the smallest sprocket rubs against the nut, and both of them have a ribbed surface.

After unscrewing the nut, remove the wrench and puller and remove the entire cassette. Do it carefully: special gaskets are laid between the stars, try not to scatter them when dismantling, they can easily get lost. Next, carefully lay out the parts of the wheel system in the order in which they were removed so that nothing is confused during the subsequent installation. However, if you need a complete replacement of the cassette, tk. the old one has fallen into disrepair, then you can simply throw it away. However, first you should carefully examine the parts, assess the degree of their deterioration. perhaps the stars will still be able to withstand one season without harming the entire transmission.

How to wash and lubricate?

If you decide to leave the old cassette, then before putting it back on the drum, the mechanism must be cleaned and lubricated. Cleaning these bike parts is very easy: put the sprockets in a container of hot, soapy water, leave for a while, and then use a brush to wipe off any dirt and old grease residues with force. Next, wipe the sprockets and washers with a dry cloth and leave to dry completely.

By the way, if you decide to completely replace the cassette, the new system must also be lubricated before installation.

Installation

So, the parts are washed or bought again, the sprockets are lubricated. a new and clean set of sprockets can be installed in the system. Observe the reverse order of removal. First, the largest stars are put on the drum and then in descending order. Remember to insert washers between them. Last of all, a nut is put on the wheel mechanism, a ring-shaped puller is installed on it, exactly in the grooves.

When the nut is installed, tighten it with an adjustable wrench as tight as possible: it is very important that the system does not unwind while riding, this can pose a serious danger to the cyclist’s health.

If you are changing the rear system completely and you are faced with the question of choosing a new cassette, pay attention to the material for making the stars:

  • If they are made of aluminum, then such a block will have a low weight, but this will make it more expensive. Such equipment is usually bought by cyclists with previous experience; beginners can choose something simpler;
  • Steel stars are the most popular in the cycling environment, they are moderately durable and withstand more operational loads, among the disadvantages. a lot of weight, but they have a low price. Good for beginners and those who rarely ride a bike. Since steel easily rusts, parts made of it must be coated with nickel, chrome or other anti-corrosion compound;
  • Titanium cassettes are lighter than steel, but heavier than aluminum, they are the most durable and suitable for experienced riders and extreme sports enthusiasts. Such a detail will serve for a long time and faithfully, however, it will not be cheap.
remove, sprocket, block, bicycle

Removing the ratchet and cassette

The rear sprocket block (cassette) is mounted on a ratchet. Maintenance of the cassette is reduced to cleaning it from dirt that gets between the sprockets.

The device of different cassettes is approximately the same, they differ only in the number of stars (from 5 to 9) and the way they are attached to each other. On many cassettes, the sprockets are simply tightened with screws. In this case, the most worn sprockets can be replaced with new ones. Sometimes a block of sprockets is made non-separable (sprockets are riveted into a single block). This increases its strength, but then when some sprockets wear out, you will have to change the entire cassette.

There are various ways of attaching the ratchet cassette to the hub. Modern imported bikes contain rear hubs with wound ratchets. The body of such a sleeve has a thread on the right side, onto which the ratchet is screwed together with the cassette.

If you have 7 or fewer stars, then, most likely, the stars have a ratchet in themselves and to remove them, a puller is needed to unscrew the entire ratchet as a whole. Actually, there are 7-speed cassettes too, just a different hub is used for them. with a shorter drum. If the number of stars is 8 or 9, then a cassette hub is usually used and the ratchet is installed on the hub.

Removing the ratchet (for hubs with screwed-on ratchet)

On such bushings, the cassette is removed together with the ratchet, therefore, when adjusting the bearings or replacing the spokes, it is not necessary to disassemble the cassette. This only needs to be done to replace the sprockets themselves.

To change the spoke on the right side of the rear wheel or to change the grease in the bearing, the cassette can be removed with the ratchet without touching the hub axle. The inner surface of such a ratchet has slots into which an appropriate puller must be inserted. The sprocket block rotates here on the ratchet body. The body itself is screwed onto the sleeve and the puller is inserted into the body.

We insert the puller into the slots on the ratchet, and turn it off with an adjustable or open-end wrench. Unscrewing may require considerable force. We recommend using a gas wrench or a long-handled wrench of 24. The ratchet thread is left, unscrewed clockwise (against the freewheel of the ratchet).

Then we remove the cassette together with the ratchet and the protective plastic ring.

If you are going to replace a wheel, leaving the old ratchet, then buy a wheel with a hub just for the ratchet. With such a hub, you will see only the axle without the hub drum.

Removing the cassette

You have to remove the cassette, firstly, to adjust the bearings of the rear hub (in principle, you can not remove it, but with the cassette removed, it is more convenient to adjust the hub), or to replace the sprockets themselves. If during a trip you have to replace the rear wheel spoke on the right side, then the cassette will also need to be removed.

The cassette is tightened to the ratchet with a slotted nut. In order to unscrew this nut, you need a special tool. cassette remover. And in order to hold the cassette (you have to unscrew the cassette in the direction of free rotation of the rear wheel counterclockwise), you need a whip.

The cassette sprockets are put on the ratchet body and tightened with a wide nut of a special shape. A bushing with a built-in ratchet mechanism is used. Plastic washers are inserted between the sprockets.

When disassembling a cassette, it is necessary to take into account that not only the order of the asterisks is important, but also their orientation relative to each other. Washers can also differ in diameter and thickness, so it makes sense to carefully lay out all the removed parts in a row.

To unscrew the nut, you will need a special spline wrench, and to keep the cassette from turning, you need a whip, because the direction of rotation of the nut when unscrewing coincides with the direction of free rotation of the ratchet.

We put the whip chain on the largest sprocket of the cassette. We turn off the nut with a wrench, holding the cassette with a whip. If you don’t have a whip, you can use the old chain instead, securing it in some way so that it holds the spider. You can also use an old thicker and larger rag. We fold it in several layers and throw it on the spider, holding it with our hands. The spider is held with its entire palm through a rag and turns with a key.

Remove the nut. Then we remove all the sprockets and washers from the ratchet body, observing their order. If necessary, remove the bushing drum from the axle.

Shimano Cassettes & Ratchets

It is necessary to remove the cassette, firstly, to adjust the bearings of the rear hub or to replace the sprockets themselves. If during a trip you have to replace the rear wheel spoke on the right side, then the cassette will also need to be removed.

In fact, there are no fundamental differences from the method described above. A special feature only in the used puller: it must have an axis that is inserted into the cassette.

The only difference is that several small sprockets can be put on the ratchet independently, and there must be washers between them. gaskets. These sprockets and washers must be carefully removed so that they do not fall apart during disassembly. It is better to remove them one at a time, and carefully lay them out somewhere so as not to be confused during assembly.

This applies to Shimano HG-30 / HG-40 / HG-50-8 eight-star cassettes.

Removed Shimano cassette: