Bicycle hub repair and maintenance
For a successful subsequent assembly, it is better to repair the hub on the removed wheel, but without dismantling the spokes. The steps in the process are as follows:
How to Replace a Wheel Axle on a Bicycle
- The cassette is removed from the axis using a special tool (puller or whip).
- Retaining ring opens.
- Washers and loose bearings (industrial bearings) are removed. The main thing is to remember the location of the parts, so that later on to make the correct assembly.
- Bearing diagnostics. Defective parts are replaced with new products. If they are not yet worn out, then they should be cleaned of dirt with a solvent.
- Complete axle removal.
- Cleaning the body from dirt. To do this, use only a soft cloth, wiping each cavity with it.
- All elements are sequentially lubricated. First, a small amount of the substance is distributed along the walls of the housing. Bearings can be more lubricated.
- The final process of repairing the rear wheel hub of a bicycle. Reassembly is carried out in the reverse order, including the installation of the stopper and tightening the fasteners.
Do not use too much force when tightening the rear wheel hub. The bike should move freely, and not barely drag.
Instructions for Removing the Wheel Hub Bolt
1.Remove the wheel hub bolt using a press.
Falling wheel stiffness
The wheel is the most loaded part of the bike. During operation, the wheels have to withstand shock loads of different magnitudes, as a result of which the rim profile can have dents and other deformations.
The new wheels, centered by the robots at the factory, still have residual spokes, but after a short run down the street, they stretch. With a strong impact, the hub axle may deform, which will cause the wheel to turn eight even if there is a perfectly flat rim.
Very often, overtightening of the spokes will result in a drop in the correct stiffness of the wheel. Disc brake operation promotes the development of the umbrella when the spokes on the side of the rotor attachment are slowly loosened. As in the case of a drop in frame stiffness indicators, all this leads to an increase in the likelihood of breakage and more noticeable deformations in the future.
Wheel Hub Bolt Installation Note
How to remove the axle on a Shimano XT 785 hub with loose ball bearings. #1
Install the new wheel hub bolt using a press.
© 2012 Mazda North American Operations USA
The fork and shock absorber are used to minimize shock loads, thereby enhancing ride comfort. Pneumatic chambers or compression springs act as elastic suspension elements, and closed-type cartridges or open oil baths are used as damping elements.
Springs tend to lose their elasticity, sagging more and more. Pneumatic chambers are sealed using special rings, which also wear out a lot, starting to let air through.
The oil collects wear products and loses its damping properties, and the O-rings and fork oil seals leak, leaving marks on the feet and allowing air to pass through. Ignoring the need to replace oil seals, anthers and o-rings will inevitably lead to backlash due to problematic bushings (guide bushings in the fork). The diameter of the fork legs ranges from 28-40 mm.
Most often, the diameter is 32 millimeters. Increasing the diameter of the legs automatically increases the reliability of the forks by increasing torsional stiffness. Suspension wear also manifests itself in a change in the color and texture of a special coating of rubbing parts. legs. Different forks use different methods of spraying. Teflon, anodizing, chrome plating, polishing. The main cause of wear on the foot cover is complete wear on the bosses, which guide the feet straight into the inside of the fork, preventing any play in the pants.
How to Install Rear Wheel Hubs and Bearings on PT Cruiser
The rear wheel bearings are permanently sealed assemblies within the hub and are not serviceable on the PT Cruiser. A failed wheel bearing requires replacement; however, the hub requires several special tools and a powerful press to remove the pressed-in hub bearing. These tools are not commonly found except in mechanical workshops or service centers. Removing a hub and sending it to a facility that has these tools is the easiest and cheapest way to get the job done.
Algorithm for device installation
In order to install a planetary hub on a bicycle, you will need the following tools:
- Small adjustable wrench or 15 spanner spanner. Do not use a regular open-end spanner. It can damage the edges of the nuts with which the sleeve is attached to the frame, since they are tightened with great effort.
- Awl or small flat screwdriver for mounting and dismounting the sprocket retaining ring.
- To install the 8-speed hubs, you will also need a 2mm hex wrench. With its help, the cable will be installed in the switching mechanism.
- A regular open-end wrench for 17. The thickness of its jaws should be 2 mm. It is required for mounting the hub in 8 speeds and roller brake. The key must fit between the roller and the frame.
- To install the brake lever on the frame, you need a 10 open-end wrench and a set of hex keys.
After all the tools are available, you can start assembling the device. Initially, we set the asterisk. Depending on the type of frame, the shift of this part relative to the front and rear mowing line of the chain should be from 5 mm to 1 cm. After installing the sprocket on the bushing in special grooves, fix it with a retaining ring. Then it is imperative to put a plastic boot on the bushing driver, which will reliably protect the mechanism from dirt.
Next, you need to install the shifting mechanism on the hub driver, aligning the red marks on the part and the hub so that they are located on the same mowing line. After that, it is necessary to put a locking ring, also combining special marks and turning the ring all the way to 45 degrees.
If the hub is not with a coaster brake, then a roller brake must be installed on it. The roller must sit tightly on the hub body, and its lever must rotate freely enough. The disc may wobble slightly on its support.
The installation of the glider hub assembly on the bike depends on the type of location of the dropouts. The whole structure is fastened with a lock washer. However, vertical, horizontal and inclined drops are different from each other and require different options for locking parts.
It is important to take care when tightening the lock washers so that the shift bracket does not touch the frame itself. To do this, you can lay a screwdriver or other part between these elements, which will need to be pulled out after the end of the work.
It is not difficult to replace the planetary on your own with a new device of the same type. Whether it is advisable to install such a transmission on a bicycle, each cyclist must decide for himself.
The difference between a ratchet and a cassette
Do not confuse a bicycle ratchet with a cassette, as they are not interchangeable. Currently, the former can only be found on old and very cheap bicycles. On modern bicycles, a more advanced part is used, such as a cassette.
The main drawback of the ratchet is its incompatibility with the 15 mm diameter hollow shaft of the new QR15 standard. Loose loading from off-center sprockets can cause local bending on the hollow axis.
On the inner part of the ratchet there are ratchet pawls, on top of which an outer sleeve with sprockets is installed. The role of the nut holding these two parts is played by the cone, which is the working surface for the ball bearing. Inside there are two bulk bearings, each of which is assembled from balls of the same size.
The hidden part of the ratchet. the inner sleeve. is screwed onto the threaded part of the rear wheel, and to remove it, you need a special puller.
How to disassemble and remove a ratchet on a bicycle
The bicycle ratchet, popularly also known as the nut, is a ratchet mechanism that allows you to reliably transmit torque through the chain from the pedals and at the same time coast freely without the need to pedal continuously. This mechanism is assembled as a single piece with the rear wheel hub. Consists, in fact, of the ratchet itself in the form of a toothed drum with two pawls and a non-separable cassette of sprockets.
Simple maintenance of the bike transmission boils down to cleaning it from dirt and grass that gets clogged between the sprockets.
You will need to remove the ratchet from the bike in the following cases:
- To adjust the tightening of the rear wheel hub bearings. You can not remove anything, but with the cassette of sprockets unscrewed, it is much easier to remove the ball bearings, determine the degree of wear of the cup, lubricate the assembly.
- If possible, to replace broken dogs. Although such small parts are not sold individually, and most often you will need to buy the entire assembly, they can be removed from the old ratchet. Unfortunately, there are times when, as a result of the premature death of the dogs, the drum with asterisks either gets jammed, or it starts to rotate freely in both directions.
- When the teeth of the smallest stars are worn out to the extreme or if one of them breaks.
- To install the spoke into the rear wheel hub on the right side, to replace the broken.
Removing the Ratchet from the Bicycle
How to disassemble the ratchet is clearly demonstrated in the following video:
When pedaling, a fairly large torque is transferred through the chain to the wheel axle, in particular, when driving downhill. With exactly the same force, the inside of the ratchet is threaded to the rear wheel hub.
It always takes a decent amount of effort to unscrew a long-established nut, which can only be transferred with prepared tools. These tools include a slotted bushing-like puller and a large wrench.
The ratchet remover cannot be replaced with a similar but cassette-specific attachment. They should not be confused as they have absolutely incompatible splines.
Unscrewing a stuck ratchet
It so happens that there is not enough effort to disrupt a rattle that has been tightly tightened for several years. In this case, lengthening the key lever will help.
Many in the garage will find an iron pipe or bar about 60 cm long.Then, you can simply put this pipe on the handle of an adjustable wrench or the tooth of an open-end tool, or do a tricky thing and assemble a two-arm lever.
- Take a couple of short, 6-8 cm long bolts M8 or M10 and pick up two corresponding nuts for them.
- Insert one of the bolts into the hole in the ratchet puller, and thread the other through the hole in the handle of the adjustable wrench. These bolts should be secured with nuts to hold them in place.
- We insert the pipe between two bolts: the puller installed in its place and the adjustable wrench put on it. Now all that remains is to push the resulting lever down to disrupt the ratchet.
Usually with a lever from 50 to 60 cm, any rattle is unscrewed in almost one motion.