How to replace a rear hub on a bike

Reverse side of the medal of planetary bushings

  • High friction and responsive gears make planetary bikes unsuitable for racing.
  • The 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 bike 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.

How To Replace A Freehub Body On A Bike Wheel

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 the fundamental difference from the “star” transmission, this gearshift system is in good demand in the world of bicycles.

Bicycle Rear Hub Repair

replace, rear, bike

Rear hub failure is one of the main problems faced by bike owners. This is not surprising, because no matter how carefully the owner takes care of his “iron friend”, the rear hub will still be the most loaded part of the bike. In addition, the bearings in the bushings 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 we will talk about 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 the bearings and the severity of the stroke. If both problems occur, you must immediately start troubleshooting.

The rear hub of the bicycle, its structure and maintenance

The service life of a bicycle directly depends on the quality of its service. For example, repairing the rear hub of a bicycle can be done by hand. Although the bushings can be of different designs, the principle of their 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.

In this article, I will show you 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 located 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 counterclockwise movements.
  • 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.

This washer is sized to be inaccessible 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 in order 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 on top of it we screw the restrictive nut.

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.

When a bicycle rear wheel hub repair is needed

Timely maintenance of the rear hub keeps the part in good condition. Periodically it is 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 move 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 lack of lubrication are determined by the deterioration of the roll, the occurrence of extraneous sounds.

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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 that of a conventional single speed.
  • Protection against external influences on gear shifting is due to the secrecy of the 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.

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 such 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.

Bicycle Rear Hub Maintenance

If you ignore the need for periodic maintenance of the rear hub of a bicycle, then the life of the “iron friend” can be greatly reduced. Experienced cyclists know what signs will indicate to disassemble / lubricate / reassemble the rear hub immediately. This process is not difficult, but you need to do everything in a certain sequence.

When to Service the Rear Hub

To ensure that bike parts are always in perfect technical condition, they must be regularly serviced. If we consider the rear hub of a bicycle, then for it you will need:

  • periodically tighten the body;
  • regularly change the bearing balls;
  • at the next disassembly, lubricate all internal parts of the case;
  • adjust the brake hub from time to time.

Dismantling the rear wheel itself is as easy as shelling pears, but the process of removing and disassembling / assembling the rear bicycle hub is much more difficult. And nevertheless, without such regular maintenance of the part in question, it may soon need to be overhauled or replaced.

Signs that indicate an urgent need for service on the rear bicycle hub:

  • when driving, there is a strong wheel play;
  • the crunch of bearings is clearly audible (this means that they are simply worn out);
  • on the go, the bike body rattles and staggers;
  • rolling dynamics is bad.

It is worth knowing some of the features of eliminating a particular symptom:

  • If the rear hub casing is spinning, its looseness, then this can be eliminated by tightening the fastening nuts.
  • If the movement of the rear wheel is difficult, then it may be necessary to loosen the retaining nut a little. most likely, too much force was applied when tightening it.
  • If extraneous sounds appear when the bike is moving and the roll-forward deteriorates, you will need to replace the bearings or completely lubricate the rear hub housing.

We work with the inner space of the bushing

After the axle has been removed, you need to carefully inspect it. As a rule, this part of a bicycle wears out very rarely, but in any case, you will need to thoroughly wipe it off from dirt and dust. This is done with a dry cloth, but in some cases (if heavily soiled) you can use gasoline. So, we wipe the left cone and examine the right one for fastening strength. Only after the axle walls are completely dry (if gasoline was used for processing), can new grease be applied to it.

Note: in no case should you use chain lubricant or some other lubricant for the rear hub of the bicycle. you will need to purchase a special tool. Bearings are often used for bearings. this lubricant will be the most suitable. Too thick a layer of grease should not be applied. during the operation of the bike, it will be squeezed out and actively absorb dirt, which leads to rapid wear of the part.

How to properly disassemble, clean and lubricate the rear hub

Immediately remember one truth: any service is recommended to be carried out with a snagged sleeve. Otherwise, the chances of assembling the wheel correctly and quickly are unlikely to work. this can only be done by a person who is already experienced in servicing bicycles.

Step-by-step instructions for maintaining the rear bicycle hub:

  • Remove the cassette from the axle using a whip and a puller.
  • Opening the retaining ring.
  • We remove all bearings and washers.
    Note:the sleeve can be on industrial bearings and bulk bearings, but in any case, it is very important to remember their original location in the sleeve. This rule must be observed when removing the washers.
  • We carry out a careful inspection of the bearings. if they are damaged, then this means the need to replace them with new parts.
  • We take out the axle. it does not understand.
  • We clean the body of the rear hub of the bicycle from dirt. All internal cavities must be wiped with a dry cloth.
  • When installing back, each part is thoroughly lubricated, special attention should be paid to the bearings during this process.
  • The last step is to install the stopper and tighten the fastening nut. It is not necessary to apply great efforts to tighten, as this can result in a problem of free wheel rotation.

Of course, everything looks quite easy and simple, but there are a lot of nuances in servicing the rear hub of a bicycle. they must be known and taken into account in the process of work:

  • Firstly, the direct disassembly of the bushing should be started only after the cassette has been removed. over, the sleeve is disassembled from the opposite side and, as a rule, it is on the left. The locknut, if any, is unscrewed with a 15 mm wrench, then the stopper is removed (again, if any).
  • Secondly, you need to be extremely careful when removing the washers and rings. they will need to be laid out on a pre-prepared sheet of paper in the exact order, if this moment is overlooked, the assembly of the rear bicycle hub after cleaning and lubricating it can turn into a real torment.
  • Thirdly, after twisting the housing of the rear hub, its axis will begin to give in. just at this moment the bearings will appear. And again, you need to be extremely careful when removing the bearings. the parts are small and easy to lose. We remove each bearing with a knitting needle or tweezers, carefully wipe it with a rag soaked in kerosene or gasoline, and put it aside. Just in the process of wiping, the bearings must be carefully inspected for damage, and if there are any, then the part must be replaced.
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Note: in the articles and instructions for servicing the rear hub of a bicycle, you can find a recommendation to use acetone to wipe bearings. this is permissible, but it should be borne in mind that the aroma from such a product will not be the most pleasant, and acetone can corrode the skin on the fingers. And one more thing. many “kulibins” in order not to lose small bearings use a magnet. in no case should this be done! The fact is that the bearing is magnetized and during the operation of the bicycle, iron dust is attracted to these small parts. the fact that the hub will soon become unusable can be predicted with confidence.

It is highly undesirable to confuse the left and right parts when disassembling / assembling the rear hub of a bicycle. this can lead to wheel play. If at least one ball is lost, then you will have to carry out a full replacement of the bearings. Sometimes, when opening the bushing near the axle, you can observe iron “dust”. this means that the bearings are completely worn out, they must be completely replaced.

How to carry out the installation correctly

After carrying out the above work, you need to assemble the bushing to its original position. This is done in the following sequence: right bearings. wheel axle. cone. left bearings. stopper. washers and rivets. lock nut.

It is almost always necessary to adjust the rear hub of a bicycle after assembling. This is done only on the left side. first, the lock nut is slightly loosened with a 15 mm wrench, then it is tightened to the stop, but the cone must be held in a fixed position.

Using the described method, you can completely get rid of the axle backlash, at least. reduce it to a minimum. Most likely, you will have to carry out the same operation more than once, but you need to achieve synchronous movement of the axle and wheel.

Note: slight cranking is quite acceptable, but tightening the lock nut too tight can lead to difficulty in movement.

This completes the maintenance of the rear bike sleeve. It will be necessary to check the quality of work. test the “iron friend” at different speeds, determine if there is a backlash, how tightly all the details are fixed, if there are any extraneous sounds. If something does not suit you, then the process of disassembling / assembling the rear hub will need to be repeated.

Maintaining the rear hub of a bike is not a daunting task. even a beginner can handle the job. But if you cannot disassemble the bushing on your own, then you need to contact a specialist. with strong pressure on the part, it can be damaged, which will require a complete replacement.

Some helpful tips before starting:

For this job, you will definitely need a suitable size taper wrenches 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 protect 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, a 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. All of this does not work at all with bent axles or damaged cups and cones. These parts need to be replaced in order to properly adjust the bushing.

Bulkhead and bushing repair

The cup-cone bush uses loose bearings and can be easily tensioned, unlike most industrial bearing bushings, which are not adjustable. In them, the “cup” serves as the outer ring for the bearing balls, and it is pressed into the bushing, it cannot be replaced, and the “cone” serves as the 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 they rotate between the cup and the cone. The tension of the bearings is adjusted by twisting 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 generally symmetrical, although the bushing is often moved slightly to compensate for the rotor mountings. A freewheel drum (a ratchet mechanism that allows rolling) is installed on the rear bushings 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.

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 need to be removed to get to the cone and its edges to fit the wrench. If you are working with a rear hub, you will 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 lock nut 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.

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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 when assembling.

At this point, you should 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 use several thin washers. Washers not only allow the taper and locknut to be pulled together without risk of loosening the tension, but are also critical to positioning 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.

Bike Wheel Problems? Try Replacing your Hub!

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

Grease is 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 axis, it must be inserted from the side from which 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 the other 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 shaft is slightly compressed when it is clamped in place.

Rotate the eccentric bushing axle with your fingers. it should rotate freely, smoothly, evenly, but with a slight backlash. Place it on the 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.

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 loosened, turn the wrench on the taper clockwise about 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 make adjustments in small steps, you will most likely need to do this several times before the adjustment is perfect.

For a final check, open the eccentric handle of the clamp a little (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 that they are the same as before disassembling the sleeve and that this number is the same on both sides. Wipe off any excess grease.