How to Change the Rear Hub on a Bicycle

Bicycle hub replacement

The hub is an essential part of the bike design. Both bushings support the entire weight of the rider and the bike itself. All loads during landing and impacts in case of unevenness are also taken by the hub. Therefore, breakdowns due to which the hub is replaced on a bicycle are very common.

In this article, you will learn how to change the hub on the rear and front wheel of a bicycle, we will understand the types of bicycle hubs and talk a little about their maintenance.

Types and design of bicycle hubs

Before doing anything with the bushing, you first need to understand its design. How to change the hub on a bicycle will become clear when you understand its design. All bushings have 4 main components:

  • Housing. The spokes attach to the body and connect it to the rim. The body has cups on the sides, into which the bearings are inserted, it is hollow inside. An axis passes through the body.
  • Bearings. There are two types: bulk. balls fill the cups of the body; industrial bearings. the balls are housed in a closed structure and are a one-piece bearing. Sometimes there are balls of a non-closed type that are simply held together by a metal shape. Bearings allow the housing to rotate around an axis.
  • Axis. The connecting link of the bicycle and the wheels, bearings with the body revolve around it. The axis itself remains stationary. The fastening system can be nut or eccentric. An eccentric is used on vertical dropouts to facilitate wheel removal, sometimes nuts are used on cheaper models with such dropouts. Nuts are needed on horizontal dropouts where there is no chain tensioner and single speed transmission to make it easier to center the wheel and tension the chain. The eccentric axis is hollow with a hole inside through which the eccentric is attached.
  • Retaining nuts, eccentrics, locknuts and guides. The guide is screwed onto the axle thread first so that the bearings remain in their position. The locknuts fix the position of the rail on the body. The nuts are screwed onto the axle from the outside of the dropouts to secure the wheel position. Eccentrics perform the same function.

This design completely describes the front hub, but the rear is also part of the transmission. Rear sprockets are attached to it. Replacing the rear hub of a bicycle does not require replacing the chainrings if they are in good working order. Rear hubs differ in the type of sprocket mounting:

The sleeves also have a different number of holes for the spokes, different flange heights, different widths or O.L.D (Over-Locknut Dimension. measurement of a locknut. Length is measured with fully tightened locknuts on the hub (not on dropouts) from one locknut to another). You need to choose the right hub for your dropout width, chainline and the number of spokes on the rim.

How to disassemble and reassemble the sleeve

Disassembly and replacement of parts of the front hub of the bicycle

To carry out the parsing procedure, you will need several wrenches. Wrenches 13, 14, 15, 16 and 17 mm may be needed. The most commonly used wrenches are 14 and 15 mm. Sometimes a thin pair of wrenches are required to remove the small locknut and not damage the structure.

Remove the retaining nuts from the dropouts. Most often a 14 mm wrench is needed.

Remove the wheel from the bike. If you have a rim brake, you need to remove the pads so that the wheel can be removed.

Unscrew the locknuts. Here you need 2 keys, locknuts can be for different key sizes and for different widths. It is necessary to hold one key on the thread of the guide, and the other to unscrew the lock nut.

Remove the guide and pull out the axle. At this point, the guides can be removed by hand.

Advice: if you cannot remove something, then do not rush to do it with great force so as not to break the tool or sleeve. Perhaps some detail matched the other. With this problem, you can use the anti-inflammatory chemistry WD-40.

Pull out the bearings carefully. If you have them of a bulk type, then prepare the place of work so that they are not lost. The balls are not connected in any way to anything, so they can easily fall out and get lost. If you have industrial bearings, you will have to gently pry a thin plastic part with something to get to the balls.

Tip: Separate the balls from the right cup and the left cup, most likely they are already slightly deformed. In order not to propagate the deformation to another cup, it is best to always insert the bearings in their previous place.

Replace the bearings. Spread the balls evenly around the edges of the cup if you have a mound. Industrial just enough to slide into place.

Insert the axle, tighten the guides and locknuts. Make sure that the axle protrudes from the cups without skewing in length on one side. Slide the guides and lock nuts onto it. If you have loose bearings, then a dilemma can arise: tighten tightly and eliminate the play, or leave play, but allow the bearings to rotate freely. If the backlash cannot be eliminated without strong twisting, then it is best to leave a small space, but not bring the hub to a state of complete deformation while driving.

Replace the wheel and tighten the nuts. Make sure that the wheel is level, without distortion.

How to disassemble and replace a part for a rear hub on a bicycle

Rear hubs are part of the drivetrain, so they have an additional mechanism that depends on the type of bike drivetrain:

Before you ask the question: how to change the hub on the rear wheel of a bicycle, you need to identify the cause of the breakdown. To do this, first disassemble it according to the instructions in accordance with the type in the bushings

Rear ratchet hub. The principle of operation is the same as with the front one, but after dismantling the wheel from the bike (after Step 2.), you must remove the ratchet with a special puller and a wrench and continue with Step 3.

change, rear, bicycle

Rear hub for cassette. After dismantling the wheel (Step 2), remove the cassette with a special puller and a whip. Dismantling the drum consists in removing the lock nut and guide, after which you need to carefully remove the drum from the axis.

The fixed and single speed hubs are disassembled in the same way as the front ones, you don’t even need to remove the sprocket. If you have a BMX, then you have to remove the “driver”, it is removed like a drum for a cassette. Sometimes there are single-speed bushings with a foot brake, for example, on a bicycle “Ukraine”, there you also need to pull out the brake mechanism.

The planetary hubs are very difficult to service due to their complex design, they usually do not require maintenance at all due to the closed mechanism. There is no single principle of maintenance of all planetary systems; each model should have its own instruction. The process is something like this: after unscrewing all the nuts, you need to remove the housing cover and take out the core. If you managed to do this, then you need to disassemble all moving mechanisms for service. It is important to remember how everything was originally, if you are doing it for the first time, so that you can collect it.

Service

For the sleeve to last long, it must be serviced regularly. Maintenance consists in cleaning the bearings and housing cups from old grease that has already collected enough dirt. Black grease indicates dirt is present. This grease must be changed to prevent dirt from destroying cups and bearings.

When you have completely disassembled the bushing, wipe the old grease with a rag or paper from the bearings and bushing housing cups. Apply new grease to cups and bearings. Next, assemble the structure.

Replacement

Do not rush to change the entire bushing at once, first identify the breakdown. Sometimes you can get by with replacing just one part: a bearing, axle, drum, or even one nut. The cost of one part will be much lower than the whole bushing. Disassemble the bushing, identify the breakage and replace the defective part.

If the body is deformed to such an extent that further operation of the bushing is impossible, then you will have to change it completely. In such a situation, you will have to re-spoke the wheel, i.e. remove all the spokes from the hub and rim and put everything back on, if you do not mind the knitting needles, then you can simply cut them off with pliers.

How to remove the rear hub on a bike. How to replace a hub on a bicycle

The bicycle does not require special expenses for repair and maintenance, therefore it is one of the most economical vehicles. Nevertheless, in order for it to serve faithfully for many years, it is still necessary to pay some attention to it. This is especially true for those parts that are subject to heavy loads, such as bushings.

In this article, I will explain how to replace the hub on a bike.

First of all, you need to remove the wheel, after which we take out the eccentric from it. After that, using adjustable wrenches, remove the side locknut, which is on the right side. On the left and right sides there are bounding cones, one of which must also be removed to remove the bushing.

Here you can quickly find what you need!

Bushings are available with loose or housing bearings. When unscrewing the cone, make sure that the bearings are not lost. To do this, they must first be removed with a screwdriver or other tool, or carefully knocked out.

  • We clamp the right cone with a screwdriver in order to fix it.
  • After that, you can easily unscrew the axis with your fingers from the far cone, making movements counterclockwise.
  • In this case, it is important not to lose the balls that are there in a special cup.
  • Next, we take a new bushing and carefully remove the nut from the side where the additional washer is.
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This washer is designed for a distance that will not be accessible under the star on the right. Next, you need to put all the bearing balls in place, and then insert a new bushing, from which the nut was previously removed on the left side.

  • Then we wind the cone that comes with the sleeve.
  • In the event that the bike model does not provide for it, then this element can be removed and only the nut can be used. If you cannot tighten it enough, you can use a screwdriver to fix the right cone and screw it on from the left side.
  • In this case, the sleeve must necessarily scroll, but there must be no backlash.
  • Then we put on the extension washer, and screw the restrictive nut onto it from above.

When everything is ready, the eccentric should be replaced. It must be inserted into the wheel so that the foot is on the side opposite to the star. A spring is put on the axis, which protrudes from the side of the star and is twisted. Next, put the wheel back on the bike.

Bicycle Repair: How to Maintain a Rear Hub on Industrial Bearings

Today our test subject will be the Hope Pro 2 EVO hub, and it will be accompanied by an old Axiom hub, previously used on complements from Norco.

List of tools that we need:

  • Hex keys to remove the wheel
  • Whip key or old chain
  • Cassette remover
  • Clamps or vise
  • Open-end wrenches 17 and 19
  • Mallet

Let’s start the service. But first make sure you have a bike and free time.

Obviously, you must first remove the wheel from the bike. If you have a Shimano derailleur with Shadow, remember to turn the SHADOW control lever to OFF.

Or if you have a SRAM Type-Technology derailleur, remember to lock the derailleur foot with the lock button. This will forgive the removal of the wheel.

Now remove the wheel. I, on the Iron Horse Sunday frame, need to unscrew the 2 4mm hex bolts that fix the axle, and then unscrew the axle with a 6mm hex. It is likely that you have a slightly different design, but I am sure that removing the wheel will not cause any problems for you.

We remove the cassette. To do this, we need a puller, like this:

We insert the puller into the cassette:

If you start turning the puller, then the cassette will simply turn with the drum, you need to fix it. For such a case, a “key-whip” was invented, a lever with a piece of chain. Throw it clockwise around the star.

If there is no key, then don’t be upset. The old chain will help you out! We take the chain, make a couple of turns around any open-end wrench / stick / curling iron of the wife, put it on the floor and press it with our foot. You can clamp the chain in a vice, if any. We wrap the free end around the cassette. Turn the puller with a key.

Voila, the lock nut has been removed and the cassette can now be removed.

Notice the serifs on the drum, these are the cassette stars. If you’re using a cassette cassette with an aluminum drum, then strong pedaling leaves such serifs. They can cause the drum to crack. So, either use cassettes with an aluminum “spider” or you should take a closer look at the steel drum if the manufacturer produces them for your hub.

We remove the drum. To remove the drum on a Hope hub, you need to remove the spacer that presses the drum against the hub and hub axle. This spacer is simply inserted into the drum, but can be removed “tightly”. To remove it, you must use clamps or a vice, having previously wrapped the spacer with any cloth so as not to scratch it. Just pinch and pull the spacer towards you.

We also have an AXIOM bushing at our disposal, which uses a different design. To remove the drum on it, you need to unscrew the two lock nuts from the axle, located on the side of the brake disc. To do this, you need 2 open-end keys, 17 and 19 mm.

Please note that the 17 mm wrench should be quite narrow, so if you have a similar sleeve, it is better to get such a wrench initially. We just had an old key, which we previously grinded off on the sides.

Different bushings have different designs, so which side should you start to disassemble your bushing from, it is better to first find out by the name of the model from the manufacturer’s manual or search on the Internet.

Having removed the spacer on the HOPE hub, simply pull the drum towards you, the hub axle remains on the wheel.

Do not lose the metal washer that is between the bushing prombearing and the drum!

Having removed the nuts on the AXIOM bushing, we also pull the drum towards ourselves, the axle is removed together with the drum, since the drum is well pressed onto it.

We clean the insides. Carefully inspect the ratchet teeth in the hub and the spring pawls on the drum. Make sure they are not damaged, remove dirt and old grease.

Twist the bearings in the bushing and in the drum. The bearing should rotate smoothly, without jerking or sticking. Industrial bearings are usually considered maintenance-free, but if your bushing has industrial bearings with rubber boots, then they can be easily removed. A small knife is needed with which you can pry the oil seal. Be careful not to damage the boot, take your time and get exactly between the inner bearing sleeve and the boot!

Inspect the bearing for wear. Remove old grease with gasoline or kerosene and a small brush. Try not to use acetone and other solvents, they are detrimental to the oil seals. Pack the cleaned bearing with new grease. Use only greases designed for rubbing units on a silicone or Teflon base! Do not use “grease” or graphite grease.

It is worth disassembling the bearings only if you feel that the bearing “sticks” during rotation. Otherwise, it is better not to climb inside, so as not to damage the boot.

Apply grease to the dog seats and springs where they come into contact with the dogs, remove dirt from the anthers, this will extend their service life.

You shouldn’t go over it with grease on the ratchet, you don’t want your dogs to slip when you pedal? And the amount of lubricant affects the sound of the bushing. So take a small amount of grease and lubricate the ratchet walls so that they are just greased, no frills. If you want the hub not to crack so loudly (are you from this planet at all?), Then lubricate the ratchet a little more abundantly.

We collect the sleeve. Slide the drum back onto the axle first in the case of the HOPE bushing, don’t forget the spacer between the drum and the bearing. Insert the drum into the hub body in the case of the AXIOM. Do not use too much force, the drum will not insert immediately, because the pawls released by the springs do not allow the drum to be inserted into the bushing. Walk in a circle with a screwdriver, pressing down on the dogs and lightly pressing on the drum to insert it.

Insert the spacer back into the drum and lightly tap it with a mallet, it will return to its place.

For AXIOM bushings, re-screw 2 nuts per axle. Make sure the nuts are tight and there is no looseness in the axle.

Reinsert the cassette. Be careful, there are grooves on the hub drum and cassette that need to be matched. The easiest way is to turn the drum so that the widest groove on the drum is on top.

Tighten the cassette using the puller with the supplied nut. It is not necessary to use a whip key here, the dogs will unclench in a ratchet and prevent the drum from turning.

Put the wheel back on the bike. Make sure the brakes are working properly, the gears are shifting, and the wheel has not moved anywhere.

Rear hub service requires skill and courage. Not everyone will dare to climb inside an unfamiliar device. But there is nothing supernatural in this, and having well prepared and finding a diagram of your bushing on the Internet, you will be able to crank it up yourself without any problems!

Bicycle rear hub repair

Rear hub failure is one of the main problems faced by bike owners. This is not surprising, because no matter how carefully the owner looks after his “iron friend”, the rear hub will still be the most loaded part of the bike. In addition, bush bearings are often clogged with dirt and corroded.

For self-bulkheading and repairing the rear hub of a bicycle, you must have the appropriate knowledge and skills. Below will be described how to fix the breakage of the rear hub without resorting to the services of specialized service centers.

The most common problem with a bike rear hub is a loose or tight cone. The first case is signaled by a noticeable wheel play, and the second. by the crunch of bearings and the heaviness of the stroke. If both problems occur, it is necessary to immediately start troubleshooting.

Precautions

Many of the bike’s rear hub components use hardened chrome-molybdenum alloys or case hardened steel, which are brittle. Therefore, we advise you to work carefully with these parts and be sure to use eye protection. When disassembling this part of the bike, we recommend that you apply the minimum possible effort, and before the first repair. practice on an inexpensive or unnecessary bushing.

Preparatory process

To repair the rear hub, you must first remove the rear wheel from your “iron friend”. On mountain bikes or sports speed bikes, eccentric clips are often used to secure it, which can be removed without the use of keys. In entry-level bikes, most often the wheels are screwed in with two nuts, which will need to be unscrewed.

Rear hub repair

Several keys are required to eliminate backlash or tighten the cone. Most often, a 17 mm open-end wrench and a 15 mm cone wrench are needed.

Troubleshooting process:

  • loosen the lock nut,
  • tighten or loosen the flare nut to the required value so that the wheel can easily turn under the weight of the nipple or reflector,
  • tighten the lock nut.

Sometimes, due to the installation of low-quality parts, the rear axle of the bicycle hub can bend or break. To solve this problem, you should completely replace the axis with a new, better quality. To make this easier it is necessary to remove the ratchet.

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How to avoid damage to the rear hub of your bike?

To prevent the occurrence of malfunctions of the rear hub, you should periodically carry out full maintenance, which consists in adjusting its cone, as well as washing the bike, cleaning its parts, lubricating or replacing bearings, washers and oil seals.

To service the rear hub you will need:

  • remove the wheel as described above,
  • unscrew the nuts located on the axle and remove it (for bushings on bulk bearings) or knock out the axle from the drum side (for bushings on industrial bearings),
  • gently pull out the bearings using tweezers (in industrial bearings, the axle most often comes out with one of the bearings, so to remove the second one, insert a screwdriver into the bushing and knock it out),
  • for bushings on industrial bearings, it is necessary to remove the drum by turning it clockwise,
  • check the condition of the bearings and, if necessary, replace them,
  • thoroughly rinse the bearings with white spirit or gasoline to get rid of old grease,
  • check axle for evenness,
  • wipe the axle, cones, wheels and bearing seat in the hub,
  • apply special grease to the bearing seat in the bushing and install the bearings,
  • lubricate the bearings,
  • insert the axle and tighten the nuts so that there is no wheel play (the rear hub assembly on the industrial bearings is carried out in the reverse order).

When it comes to servicing the bike in a slipshod manner, repairing the rear hub can be expensive. For example, sometimes due to insufficient lubrication or axle bending under the action of bearings, potholes are formed in the body of this bicycle part. In this case, a complete replacement of the rear hub, and possibly the wheel, will be required. To protect yourself from such troubles, we advise you to carry out a visual inspection of the “iron friend” before each departure and eliminate its malfunctions in time.

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Bicycle rear hub, its structure and maintenance

The service life of a bike directly depends on the quality of its service. For example, repairing the rear hub of a bicycle can be done by hand. Although the bushes can be of different designs, the principle of assembly and disassembly is almost the same.

It is not necessary to use all the necessary tools to repair the rear hub. You can get by with a minimum set, having previously prepared the workplace. It must be clean, dust-free, and free of lint and thread. Otherwise, the sleeve may be damaged.

When a bicycle rear wheel hub repair is needed

Timely maintenance of the rear hub keeps the part in good condition. It is periodically necessary:

  • tighten the body;
  • replace worn out bearing balls;
  • lubricate all body parts directly from the inside;
  • adjust the pads on the brake sleeve.

Dismantling the wheel itself is somewhat easier than disassembling and removing the bushing housing. It is not necessary to remove all parts from the spokes. Complete disassembly is required if the entire body needs to be replaced.

Although the wheel axle is an unpretentious part, it still sometimes requires repair. Components need adjustment or replacement:

  • when the body of the screen is created on the go and its instability, which is easy to determine with two fingers;
  • when there is wheel play during movement;
  • if we observe bad rolling dynamics;
  • when a crunch is heard, indicating worn bearings.

Looseness and twisting of the rear hub housing is easy enough to deal with. You just need to tighten the fastening nuts. If they are tightly tightened (and this also occurs), the wheel is somewhat more difficult to rotate. It is therefore advisable to loosen the nuts. The poor condition of the bearings or the lack of lubrication are determined by the deterioration of the roll-over, the occurrence of extraneous sounds.

We disassemble the case, clean it and lubricate it

In order for the subsequent assembly of the wheel to take place, it is better to carry out repair work on a spoked bushing. Dismantling the brakeless bushing is carried out in several stages:

  • Removing the cassette with a puller or a whip from the axial element.
  • Opening the circlip.
  • Removing washers and bulk bearings (industrial bearings). We put emphasis on their rightful place in order to then assemble the parts correctly.
  • Inspection of bearing damage. We replace worn-out elements with new analogues suitable for further cleaning with a solvent from dirty impurities.
  • Removing the axle completely.
  • Cleaning the case from dirty impurities. Wipe each internal cavity with only a soft cloth.
  • Consistent lubrication of all parts. The sequence is very important for reverse installation. First, a small amount of grease is distributed over the walls of the housing. Bearings are impregnated somewhat more abundantly.
  • We finish the whole process by installing a stopper and tightening the sleeve using fastening nuts.

Attention! Avoid overtightening the hub so as not to obstruct wheel rotation.

Be careful when repairing the bushing

The bushing design consists of many parts, for the production of which a rather brittle material was used. hardened steel or hardened chromium-molybdenum alloys. Therefore, it is very reasonable to approach the work with fragile elements with great care. It is also rational to use eye protection.

Attention! Since parts are likely to burst, to avoid serious injury, use minimum effort and protect your face or not place your face too close. Fragments tend to fly apart with lightning speed. Estimated expansion speed. from 600m / s.

During operation, the hub must be lugged into the wheel. The cassette sleeve, none of its components should be clamped in a vice.

Council. For beginners who have not performed repairs to the bushing earlier, it is advisable to initially practice on an excessive or cheap analogue. You should also follow safety precautions.

We begin to disassemble the rear hub, we remove the cassette retaining ring

We remove the inner ring of the bearing itself with two needle-nose pliers, while carefully pushing the “nose” directly into the spline groove of the outer circlip. We fix the stars well, as if turning them along the course of the free wheel. If the wheel has a right hand thread, use the same method. Rotation of the circlip must be counterclockwise.

The outer circlip has a right-hand thread. When working with a bicycle drivetrain, it is important to consider the direction of pedaling. Ideally, it should be consistent with the tightening direction. Therefore, the sleeve is unscrewed counterclockwise. When the transmission is located on the right, the rear hub is equipped with a right-hand thread.

We turn to the analysis of the rear wheel hub of the bicycle

After removing the retaining ring, we take out the cassette. We put it aside and begin to disassemble the bushing from the left plane (opposite). You will need a 15mm wrench to unscrew the axle lock nut. If there is a stopper, it must be removed and.

Important! The confusion of left and right constituent elements is unacceptable. Incorrect assembly disrupts the work of the bushing, especially backlash. If at least one ball is lost, a complete replacement of the structure cannot be avoided. Timely replace completely or partially worn balls.

We lay out small elements (rings, washers) on a pre-prepared sheet of paper in the correct sequence so as not to confuse anything during assembly. We twist the cone, after which the axis gradually gives in. Now on this very axis the bearings become visible. We proceed with caution to removing the bearing parts, prying them with a thin object (a knitting needle, tweezers will do). Soak a rag napkin with acetone (gasoline) and process all the balls. Then we put them aside. Extraction of “embankments” or industrial bearings from the other side is carried out in a similar way.

How to lubricate the axle and hub of a bicycle

So, the axis is removed. We study in what condition it is. Although its service life is identical to the working resource of the wheel, it will not hurt to clean the axle of accumulated dirt.

Wipe the inner space of the sleeve with a clean dry bandage, cotton wool or rag. Stubborn dirt is removed with a cloth saturated with gasoline. We turn to wiping the left cone, at the same time checking the fastening of the right one (where the cassette stars are located). After the walls have dried, we start applying new grease.

As for the graphite grease, it has good properties. There is practically no adhesion of dirt, but the lubricant itself becomes significantly dirty. In addition, graphite grease has a moderate resource (500 km).

Features of a bike with a planetary hub

A very common variation of the transmission of a bicycle includes a planetary hub, equipped with a gear mechanism from the inside that changes the gear ratio. The adjustment of the relative position and, directly, the engagement of the gears is carried out using the speed switch with the handle on the steering wheel. Due to its fundamental difference from the “star” transmission, this gearshift system is in good demand in the world of bicycles.

Planetary hub priorities

  • The chain has a straight course, and the leading and, accordingly, the driven stars have a very long service life. Externally, the transmission is identical to the transmission of a conventional single speed.
  • Protection against external influences on gear shifting is due to the hidden mechanism. The service life of this mechanism significantly exceeds the permissible standard of operation of cassettes and ratchets. In planetary bicycles, all gear ratios are allowed.
  • There is no need for constant maintenance of the device. Its damage is also unlikely.

Reverse side of the medal of planetary bushings

  • High friction and responsive gears make planetary bikes unsuitable for racing.
  • Sensation of weight gain. However, among planetary hubs, some three-speed counterparts weigh a little. up to 1 kg. When driving, the additional load on the wheel is quite noticeable.
  • Self-repair unlikely. To meet a service for the repair of planetary bushings is quite problematic. Due to the disposability of the planetary, repairs will not be cheap, it is more expedient to install a new analog.
  • Quite a high price. While the cost is well worth it, installing a new gearbox is not sustainable. The optimal solution is to buy a ready-made bike with her.

It is common for a bicycle with planetary hubs to travel many kilometers on a mostly flat road. It is good to have such a bicycle for a resident of a settlement with flat terrain or a large city with a developed road network. This drivetrain variation is ideal for frequent city commutes or if you don’t want to waste time on cassettes and chains.

Summary

We check the quality of the repair in practice. Using different speed settings, you need to test the bike. It is enough to listen to your feelings to understand whether there is a wheel play or not, whether it is firmly fixed. Correct renovation brings a sense of comfort and confidence in the future. With a frivolous attitude to work, secondary adjustment is inevitable.

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Do-it-yourself repairs and maintenance of the rear hub is easy. If it is necessary to replace the entire structure, it is preferable to choose a model identical to the analogue that is now out of order. If you are not sure or able to repair the rear hub yourself, it is very wise to use the services of a specialist. Otherwise, there is a high probability of damage to the part itself.

Bulkhead and bushing repair

The cup-cone bushing uses loose bearings and can be easily adjusted to tension, unlike most industrial bearing bushings, which are not adjustable. In them “a cup” serves as an outer ring for the bearing balls, and it is pressed into the bushing, it cannot be replaced, but “cone” serves as an inner ring and is screwed onto the axle.

Bearing balls are usually 1/4 “in the rear hub and 3/16” in the front and rotate between the cup and the cone. The tension of the bearings is adjusted by screwing the cone onto the axle, then the cone is fixed in its position with a lock nut (the washer between the cone and the lock nut makes it easier to tighten them together). Front cup and taper bushings are usually symmetrical, although the bushing is often moved slightly to compensate for rotor mountings. On the rear bushings, a free-wheeling drum (a ratchet mechanism that allows rolling) is installed and a cone with a locknut on the side of the sprockets can be inside the ratchet mechanism, invisible from the outside.

Bushing components cup and taper (from left to right): locknut, washer and taper.

Some helpful tips before starting:

This job will definitely require a suitable sized taper wrench and lubricant, but it will also be convenient to use a magnet, an adjustable wrench and an axle clamp.

How tight should you tighten? It is important to note that tightening the bushing bearings more than necessary will in no way prevent them from further loosening, but in fact will increase the wear of all parts. A loose bearing bushing that has been heavily tightened and ridden will likely have both the cup and taper damaged and may need to be replaced entirely. The same will happen when driving with a weak bearing tension. So how do you know when the tension is correct??

Ideally, the quick release bushing should have little knock or play when not locked into the frame or fork. This is because the hollow shaft will bend by a small amount when the quick release clamp is locked in place and removes this play. If the eccentric hub has no play when removed from the bike, it is most likely too tight. This does not apply to solid axles that are secured with nuts. None of this works at all with bent pivots or damaged cups and cones. These parts need to be replaced to properly adjust the bushing.

Required tools:

  • Cone wrenches (commonly used on 13, 15, 17 and 19mm)
  • Adjustable wrench (optional)
  • Axle clamp (you also need a vise to use it)
  • Magnet (optional)
  • Clean rag

Remove the wheel from the bike and pull out the eccentric clip, be careful not to lose the centering springs on each side. Most bushings with loose bearings have rubber boots that must be removed to get to the cone and its edges for installing the wrench. If you are working with a rear hub, you also need to remove the cassette. Recalculate the number of open threads at the end of the axis before moving on to the next step. If there is no thread at the end of the axle as shown in the photo, you can use a vernier caliper to measure.

Always disassemble the rear hub from the rotor side and the front hub from the non-rotor side. Now you need to loosen and unscrew the cones on one side of the sleeve. To do this, hold the cone with a suitable wrench and unscrew the locknut counterclockwise with another cone wrench or an adjustable wrench. You can also use a clamp on the axle to hold it in a vice as you loosen the locknut.

Place the wheel on a table to prevent parts from falling to the floor, unscrew and remove the locknut, thin washer and cone from the axle. Put them in safe revenge in the order you took them off.

Remove the axle by slowly pulling it out from the opposite side, be careful not to lose the bearing balls when you pull the axle out. Always pay attention to which side of the hub you are pulling the axle out so that there is no confusion during assembly.

At this point, you must remove the cone, washer (one or more) and locknut, as well as the axle itself. Some bushings use thick washers between the taper and locknut, while others have several thin washers. Washers not only allow the cone and locknut to be pulled together without risk of loosening the tension, but are also extremely important for placing parts at the correct distance. Always assemble the bushing with the same washers, in the same order as you removed them. Clean the axle and other parts with a suitable cleaning agent.

Now is the time to make sure that the cone and locknut remaining on the axle are tight enough. Hold the cone firmly with the cone wrench and check how tight the locknut is with another cone wrench or adjustable wrench.

Count the number of balls on each side before pulling them out. The front hub usually has ten 3/16 ” balls on each side, the rear hub has nine 1/4 ” balls on each side, although this is not always the case.

The magnet will make it very easy to remove the balls, but it is not necessary to use it. If you don’t have a magnet, you can simply pull the balls out with the tip of a screwdriver, or they often fall out on their own. Double check the hole in the middle of the bushing to make sure there are no balls left inside. Many bushings with loose bearings are fitted with a metal dust cap, which is pressed into the bushing (the silver ring surrounding the bearings in the photo) and is not designed to be pulled out. Although you can remove it with a screwdriver, you will most likely damage it. Better leave it where it is.

Lubrication. your friend. Place a thick strip of grease on the inside of the cup, it should completely cover the entire perimeter. This will also help to hold the bearing balls as you reassemble the bushing. Carefully insert the balls on both sides of the sleeve, there should be exactly the same number of balls as you pulled out when you disassembled it.

When the balls are in place, you need to insert the axle. Before doing this, apply grease to the surface of the cones where the balls will roll. Pay attention to which side you will insert the axle, it must be inserted from the side from where you pulled it out. The axle must be inserted into the front hub from the side of the rotor, and into the rear from the side of the freewheel drum. Be careful not to drop the balls from the cups.

Screw on the cone, after having lubricated its surface in contact with the balls with a layer of grease, then install the required washer and locknut. Twist the cone clockwise until it touches the balls and then unscrew it a quarter turn.

Hold the cone wrench in place and tighten the jam nut against it with another wrench. The bushing will most likely need to be adjusted further, but it is important to remember that until the wheel is fixed with a clamp, the bushing with an eccentric clamp should not fully clamp the bearings, there should be a slight backlash, and after installing and fixing the clamp there should be no backlash. This is because the eccentric hollow axle is slightly compressed when it is clamped in place.

Twist the eccentric bushing axle with your fingers. it should rotate freely, smoothly, evenly, but with little play. Place it on a frame or fork and try to feel the play by holding the top of the wheel and swinging it along the axle. If there is no play and the wheel spins smoothly and evenly, you are done. If not, continue with the next steps.

Remove the rubber boot from the bushing and eccentric clamp spring (so that the QR clamp nut only comes into contact with the outer bushing locknut) and secure the wheel to the outside of the rear triangle of the bike, the side you are adjusting should be closer to you. With this fastening, the force of the eccentric clamping should be approximately the same as when the wheel is mounted on the bike during a ride.

Place one hand on the taper and locknut on your side and the other on the rim. Gently rock the rim back and forth axially and try to feel the play in the hub with your other hand. If you feel any tapping, you will need to slightly tighten the bushing bearings.

Hold the cone in place with one hand and loosen the locknut with the other by turning it counterclockwise. When the locknut is loose, turn the wrench on the taper clockwise approximately ten degrees. Hold the cone in place with a wrench and tighten the locknut. Check for play as described in step 15 and if there is still play, repeat the process until it disappears. Save time and adjust in small steps, you will most likely need to do this several times before the adjustment is perfect.

For a final check, slightly open the eccentric handle of the clamp (so that it is at a 45 degree angle, but still keeps the wheel in the dropout) and check the hub play while keeping one hand on the axle. There should be some play, but it should disappear when the clamp is tightened.

Recalculate the number of threads on the protruding part of the axle on each side to make sure they are the same as before disassembling the sleeve and that the number is the same on both sides. Wipe off any excess grease.