The speed on the bike does not change: what to do, how to fix the problem. Bicycle speed does not switch: what to do, how to fix the problem
Always keep your bike in good condition. But in spite of everything, some parts tend to wear out, which entails certain problems. For example, the speed of the bike does not change. What is the reason and how to fix it? In some cases, the problem can be solved on site, in other situations it is necessary to replace the worn part.
The scheme of operation of switching speeds involves throwing a chain. After the shifter has been pulled, you need to turn the pedal, only after that the chain will move to another star. Extraneous sounds and clicks when switching may indicate that a changeover setting is needed.
Why the speed may not switch:
- the chain or cassette is worn out;
- the cock bent;
- switch backlash;
- the presence of damage to the cables and shirts;
- the switch has not been adjusted or the previous setting has been lost;
- the transfer cable is damaged (it may stretch, break or be close to breaking);
- broken switch;
- broken spring in the switch;
- the teeth of the rollers are ground off;
- the chain is dirty, which prevents it from rolling freely.
Therefore, if problems with switching occur, it is necessary to carefully check each of the possible causes of failure. In most cases, the reason lies in the lack of regulation or the fault of pollution. Parts can only wear out with long-term and intensive use.
Fixing the problem
The method of correcting the problem that has arisen will be determined depending on the cause of the breakdown.
Cables and shirts
One of the most common problems that amateur cyclists face is cable wear. To check the condition of the cables, you need to find areas without a shirt, and then click the shifter. This will allow you to see the inside of the cable, which should not have emerging threads. The presence of such defects indicates that it is time to change the cable.
Another important detail is the aluminum cap. This is an obligatory part of the cable that protects it from loosening. If it is damaged, then it must be replaced.
If the gears are shifted, but not always as the cyclist requires, then the problem may be in the shifting rollers or cassettes, where the teeth have worn out. The only way out of this situation is to buy a new part.
The chain becomes unusable approximately every 100 kilometers. Although the chain can be used after such a distance, it will no longer perform all tasks properly. Therefore, cyclists often have multiple spare chains.
Using new chains will allow the cassette to last longer as the worn part will not affect the rest of the bike. The “gauge” tool is used to determine the state of the chain.
[attention type = red] Important! The chain is a part that cannot be repaired, so if it gets worn out, you just need to purchase a new one. [/ Attention]
An even cock is the key to high-quality gear shifting in your bike. If it is bent, then there are two options: bend it or buy a new one. In any case, until this part becomes even, it makes no sense to even try to adjust the gears on the bike, since the idea will be unsuccessful due to damage to the system.
One of the most unnecessary accessories for cyclists is a rooster guard. Such a detail can be found without any problems in any city. But if the protection works and the part itself remains intact, and the frame cracks because of this, then the one who bought such a device will incur high costs.
Setting the switches
Derailleurs on a bike are divided into front and rear. It is the rear ones that are most damaged when driving, so it is recommended to adjust them first. The process itself will be long, as there are more stars than in the front derailleur.
[attention type = yellow] Important! It is necessary to proceed to setting the speeds on the bike only after all other parts have been checked for serviceability. [/ Attention]
Rear derailleur setting:
The basic configuration steps are now complete. The cyclist only needs to adjust the shifting accuracy. The procedure will get more complicated depending on the number of stars used.
The chain is installed on the stars as follows: in front. on the smallest, on the back. on the largest. After that, the tension screw is tightened until the roller is as close as possible to the cassette. He should not rub against the cassette.
A similar procedure is carried out with the chain, which is then installed on the largest chainring and the smallest rear chainring.
Front derailleur setting:
You will need to adjust the speeds until the chain begins to smoothly and freely change from one speed to another. If, when changing the speed, problems begin (difficult move, the chain flies, and so on), then the cable is tensioned using the adjusting bolt to the desired position.
After the manipulations with the settings are completed, the system is checked using a race, where the recommended gear ratios will be used. Adjustment is a standard procedure on any speed bike, as the tension in the cables will loosen over time. Therefore, setting speeds is often a planned activity that does not require replacement of parts.
You should not ride your bike at speeds at which there is a strong skew, 1/8, 3/1, and so on. Recommended speeds for stars depend on size:
- small. 1 to 4;
- medium. 3 to 7;
- large. from 7.
The incompatibility of the gear and the sprocket will lead to the chain sticking and spinning, which will cause the part to wear out an order of magnitude faster.
Adjusting the speed switch on the rear, front bicycle, the reasons for the incorrect switching and their elimination
Usually, advanced cyclists change the derailleurs to fit their bike exactly the equipment they want, thus making the bike fit to their needs. Beginners usually do not have to think about such an acquisition, unless a breakdown has occurred. Nevertheless, it will be useful to consider popular models.
The first models were invented in the 50s. Basically, the gear system is the front chainring. The chain is thrown from one chainring to another, increasing or decreasing the cadence.
- Fast pedaling at low speed. low gear. Combination of large front and back stars. It is designed to overcome mountains, off-road and similar areas.
- Increased for high speeds. It is a large star in the front and a small one in the back.
Switching takes place using a derailer:
- The rudder coins pull the cable.
- The frame shifts and throws the chain onto an adjacent star.
- Behind everything is the same. The patch moves from the tension of the cable and throws the chain.
Now you know how it works. There are two main product manufacturing companies:
On the steering wheel, the gears are measured using coins:
Speed selector adjustment
Setting up the front derailleur is easy enough.
However, there are some peculiarities:
- First you need to adjust the position of the front derailleur relative to the frame. You need to slightly loosen the so-called adjusting screw and set the frame horizontally. This frame must be parallel to the chain.
- The next step is to set the required front derailleur height. It is recommended to set the gap between the edge of the frame and the teeth of no more than 2 mm. This indicator is largely responsible for the quality of gear shifting.
- With the front derailleur bezel correctly positioned in both planes, secure the screw.
- After that, you need to install the chain on the largest chainring in the back and the smallest in the front.
- Use the screw to release the cable. Turn until it stops, and then unscrew the so-called adjusting drum one turn.
- Now you need to set the frame in such a position relative to the chain so that the inner side of the frame is removed by 1–2 mm.
- Pull the cable slightly and fix the screw.
- Now the big star of the system needs to be installed the chain.
- Use special screw H for adjustment.
- Check the quality of the setting.
You will need a hex wrench and a screwdriver. Place the chain over the largest sprocket in the front. At the back we put the chain on the smallest star. This is done using the speed switch, even if the settings are knocked down.
The cable on the switch is fixed with screws, which must be loosened as much as possible. There is a “drum” on the coins. It must be screwed in until it stops. And then turn it back a few turns. Rotation pulls or lowers the cable. Thus, the micro-adjustments of the switch are made. But now we are not adjusting anything, but creating the necessary range for future settings.
Find the screw H on the switch. It must be signed. Turning this screw adjusts the position of the derailleur tensioner rollers relative to the small sprocket.
Your task is to match the tensioner roller clearly opposite the small asterisk.
Now tighten the cable and fix the screw. You don’t need to pull very hard. It is necessary that the cable simply straighten out and be elastic. But it’s better to fix it as it should.
Now we throw the chain onto the largest star in the back. So far, the gears may be shifting incorrectly, because the settings are not completely finished. Don’t be scared.
At the front, the chain should be on the smallest star. And the sequence of actions is repeated. Only this time you need to adjust the position of the tensioner rollers relative to the large sprocket using the screw L. Its movement may be less noticeable, so be careful.
Now check the quality of the settings. Maybe indistinctness. To eliminate it, you need to make a few clicks with the drum. Now let’s check again the same positions where the fuzziness was.
And you also need to check the bike on the go. And to correct the indistinctness with the drum clicks. Practice will help you.
To adjust, you need a hex wrench and a Phillips screwdriver.
- We put the chain on the big star at the back. Small in front.
- Loosen the fixing screw. The position of the frame is adjusted with a screw marked LOW. Our task is to set the gap between the chain and the left side of the frame at about 0.5 mm.
- Now we fix the cable. It is not necessary to tighten too much. Switch to a small star in the back and a large one in front. There may be interruptions. As long as it’s ok.
- Using the screw, set the gap between the chain and the right side of the switch frame to 0.5 mm.
- Checking the quality of the settings. If the chain is thrown with an interference, then carry out micro-adjustments. Make no more than 1-2 turns so as not to lose the settings. Done.
Reasons for incorrect gear shifting
Many people may face some difficulties when setting switches. First, a little theory. The front derailleur does not work by itself. It works in conjunction with the stars of the system.
The stars have special nodules that are designed to make the chain switch better. The quality of switching directly depends on the state of these “pins”. If they wear out or wear out, then the switching will accordingly suffer very much.
The front derailleur itself consists of the following components:
The frame comes in different thicknesses. Internal width depends on chain width.
- You also need to pay attention to backlash.
How to fix defects
The rooster is the bracket to which the switch is attached. This is an inherently weak link, because when the switch hits the ground, it is this component that will be damaged, and the frame will remain intact, which is much more important.
By the way, there are switches that are attached to the hub axle. The mechanical strength of the system is higher, but this only applies to extreme equipment.
Titanium frames are made with fixed roosters, since the material itself is strong. Interestingly, in English it sounds like Derailleur hangar. We have stuck the name “ cock ” because of the comb at the end.
If the cock is bent, then it is better not to straighten it. It will crack anyway.
Roosters have different geometry. Please be careful before purchasing. On cycling trips, participants take extra roosters with them. And usually one bike is enough for two. They don’t break very often.
By the way, if the rooster is still broken, but you want to ride, then you can make a single speed:
- To do this, take a squeeze.
- We press out one of the pins. It doesn’t have to be a connector pin. He is thicker than the others. You must press out the pin in such a way that it does not fall out, but remains in the link. It is best to unwind not to the end and check how much the pin came out.
- Now we shorten the chain to the desired size. It is better to move the rear wheel forward in advance. We measure, squeeze out the excess links completely. By the way, the old chain is replaced with a new one in the same way.
- Install the chain in the squeeze with the reverse side. We press until the pin clicks. You can skip this click. Be careful, otherwise the pin will go further than necessary.
- It is much more convenient to use a connecting pin, the long rod of which is fixed in the links, and the excess is removed with pliers.
- Now we move the wheel, so the chain will stretch a little.
Setting up your bike derailleurs is easy. You do not need to have special skills and knowledge for this. Follow the instructions and you will succeed!
Instructions for adjusting the derailleur on a bicycle Link to main publication
Setting up bike speed switches
In this article, we’ll take a look at how to set up your bike’s derailleurs. At first glance, speed switches may seem like a complicated mechanism, although they have a rather primitive design.
Gear shifting occurs due to the loosening and tension of the cable that moves the switch. That is, in fact, switches are the simplest mechanical design, and there is nothing difficult to adjust them. The setting always starts with the rear derailleur, except when only one of the bike derailleurs needs to be adjusted.
Rear derailleur setting
Make sure the switch is not bent. If the chain tensioner (tab with two rollers at the bottom of the rear derailleur) is parallel to the cassette stars, then everything is fine.
If not, then most likely it is not the switch itself that is bent, but the cock. attaching the switch to the frame.
It is easy to straighten it by pulling on the derailleur, but do not pull on one chain tensioner! he will bend before the cock straightens, and it is no longer so easy to straighten it.
Getting started with the adjustment. Choose a higher speed at which the chain is on the smallest sprocket in the cassette (the sprocket on the rear wheel). The switch has 2 screws labeled H and L (see picture).
Turn the screw H (High) so that the derailleur roller is in line with the smaller star. Now select the lower speed. the largest cassette.
And now turn the screw marked L (Low) until the roller is aligned with the big sprocket.
After that, you need to pull the cable, while the maximum speed should be on the rear derailleur lever. Make sure the cable is firmly in the groove of the fixing bolt (shown as 1 in the picture) and tighten. Fasten the cable with a good stretch.
If high gears are poorly engaged (when picking up speed on a bike), loosen the cable tension with the adjuster (indicated by number 2 in the picture). If they are poorly reset (when driving speed decreases), then you need to tighten the cable by unscrewing the tension adjuster.
If the bike trim is more expensive, then there is a regulator on the shifter, which allows you to adjust the cable tension on the go.
Now the last adjustment. Place the chain in the front on the smallest and in the back on the largest sprocket and pedal back.
Turning the tension screw (in the picture marked with number 3), ensure that the upper roller of the rear derailleur is as close as possible to the star, but does not touch it. This is necessary for the smoothest gear shifting.
Now set the maximum speed. there is a large sprocket in front, the smallest sprocket at the back and make sure that the roller does not touch the cassette sprocket even in this position. Cheap switches may not have this adjustment.
Front derailleur setting
The front derailleur is even easier to adjust than the rear derailleur. But it is important that it is properly secured to the bike frame. When the chain is on the largest sprocket, the sprocket to derailleur frame should be 1 to 3 mm. And the frame should be parallel to the stars. If so, then you can start customizing.
Set the minimum speed. the rear is the largest, and the front is the smallest star.
Loosen the tension on the cable and turn the screw marked L (Low (where it is seen in the picture) until there is a millimeter gap between the chain and the derailleur frame.
After that, we fasten the cable with a screw (indicated by the number 4 in the picture) with good tension. You need to make sure that it lies in a special groove near the screw.
Now we sit on the bike and try how successful the gearshift settings were. If the chain does not shift well to low speed (smaller chainrings), twist the cable tension adjuster located on the front derailleur coin on the handlebar to loosen the cable tension. When the chain sluggishly climbs onto large sprockets, tighten the cable with the same adjuster.
If the chain slips with effort when pedaling, it means that it is stretched and it is time to change it. If you haven’t changed it for a long time, you may also have to change the stars with the cassette. a worn out chain quickly destroys a star.
If some certain speeds do not turn on well, check if the cable runs freely in the shirts and if there are any breaks, as well as places with unbraided cable winding. Shirts with breaks and those in which the cable runs with difficulty must be replaced, as can a damaged cable. The same problem can be caused by a bent cock.
If the switch suddenly stopped working altogether, then the problem is definitely in the cable: either it is badly tightened with the fixing bolt, or it broke.
And another important point. When changing gears, make sure that there is no skewing of the chain, due to its location simultaneously on opposite sprockets of the connecting rod and cassette, as well as on the middle sprocket and extreme sprockets of the cassette. Incorrect circuit arrangement is shown schematically in the picture. Because of this, there is a rapid wear of both the chain and the stars.
In general, setting up your bike’s gear shifters is quick (30-40 minutes) and effortless.
Why on a bike the speeds switch themselves. What do you need to know about customization? How the speed switch works. video
And this is not surprising, since such a form of transport as a bicycle is much cheaper than any average car. In addition, it does not harm the ecosystem, and is generally good for health.
And of course, like any other technique, it tends to break.
And the principle of its operation is that with the help of cables, tension or loosening of the mechanisms occurs, and the chain goes to the desired sprocket in front or behind.
How to adjust the rear derailleur on a bike
To independently configure all the mechanisms and put them into action, you need to do the following:
- you need to check if the switch itself is bent. This can be determined by looking at the tensioner. it should be parallel to the stars on the rear wheel. If it’s all about him, then you need to try to straighten it with pliers or other tools.
- if everything is fine with the switch, then most likely the rooster is to blame (this is the mount on which the switch is placed). Most often, it also bends, and it has to be straightened periodically, so that at the first breakdown it must be replaced.
If all of the above is done or in order, then you can proceed directly to setting the switch itself.
This should be done as follows:
- put the switch on the highest speed (that is, on the smallest star)
- we find two screws. H and L. Turn the screw H so that the roller on the switch moves one mark with a smaller star
- put on the lowest speed (large sprocket), and rotate the screw L until the roller is aligned with the large sprocket
- again set it to the highest speed, and pull the cable. In this case, you need to make sure that he got into the special prem. It should be pulled tighter!
- check switching! If it switches very tightly, or does not switch at all, then you need to slightly loosen the cable, or vice versa, pull it.
- if everything works well, then we can assume that the job is done.
Reasons for the malfunction of the rear spreader
The reasons can be varied. this is a bent cock or a derailleur, poor cable tension, corrosion on parts, etc. Usually, such problems occur if the derailleur is incorrectly set or no one has used a bicycle for a long time, which caused corrosion on the parts of the diverter. and its movement is difficult.
Adjusting screws on the switch
The adjusting screws are the same H and L screws used to adjust the rear derailleur. Their action is based on fixing the speed switch, which allows it not to dangle.
Usually they are accessed only once, at the first setup, and they are not touched again. But in the event of a cock or a switch breakage, you simply cannot do without them.
They are not too sensitive, so they can be safely twisted and adjusted as needed.
Cables and shirts
Special attention should also be paid to cables with shirts. The shirt is a cable sheath. And special attention should be paid to them for the simple reason that if the cable or shirt is damaged, then at the most crucial moment it may break, and subsequently switching speeds will be impossible.
Therefore, they must be chosen very carefully so that there is no damage or traces of rust, and for each cable there is a different type of shirt. There are only three of them. a SIS lash, a SIS-SP braid and a twisted braid. Based on the selected cable, the correct shirt should also be selected. Otherwise, it may happen that the cable will rub the entire sheath, and it will fail.
Rear derailleur cock
A rooster (or cockerel) is the part with which the switch is attached to the frame.
In addition, it provides more reliable protection of the frame from all-round impact, such as a fall from a great height or a large overload of the bicycle.
First of all, the rooster fails, and this saves the frame itself. After all, the rooster can always be changed, but the frame, if damaged, may not be repairable.
Therefore, this part is also very necessary, and if there is a need to purchase it, then choosing it, you should pay attention to the following characteristics: its alloy composition (what metals are used in the manufacture), quality (no chips and cracks) and of course the price.
It should not cost more than 500-600 rubles, of course it all depends on the wishes of the buyer. You can buy those that are much more expensive, but this is unnecessary.
Chains and sprockets
These two parts are the main parts of the bicycle, since they directly move with the help of them. Most often, the asterisks are cassettes. which consists of 6-7 stars. It all depends on the number of speeds on the bike.
And the chains vary in pitch and length. The chain pitch is the size of one link on the sprocket or chain, and in accordance with the pitch on the sprocket, you need to select the chain with the desired pitch. The length is basically the same everywhere, but it can also be of an individual size. Then you will have to look for it for a very long time, or rivet it yourself.
Chain tensioner rollers
The tensioner rollers are part of a mechanism that provides high-quality chain tension during gear changes or while the bike is moving. Without it, the chain will not keep at the same level, which will not allow you to pedal or switch gears.
Steering wheel switches
There are two types of steering wheel switches. lever and cylindrical. Lever are a small lever located on the left or right on the steering wheel, with which the cable is pulled.
Cylindrical switches are switches that mount with a rubber or plastic handle to the edge of the handlebars. Shifting here occurs by turning the handle down or up, then pulling the cable and moving the chain to the desired sprocket located at the back. They guarantee high-quality and fast shifting without getting off the bike and while driving.
How to fine-tune the rear derailleur
The most important factor when adjusting a switch is accuracy. You can fine-tune it as described at the beginning of the article, but during implementation you need to pay special attention not only to the adjusting screws, but also to the entire mechanism as a whole.
That is, when setting up, you need to monitor the state of the tension of the chain and cables, the position of the rollers, etc., since with fine tuning they can go to the side, which will delay the repair time for some time.
How to adjust the front derailleur on a bike
Adjusting the front derailleur is a little easier than the rear derailleur. An important factor here is its correct and reliable installation on the frame, and everything else is done within 15 minutes.
The correct front derailleur position is when the chain is on the largest sprocket and a distance of 1-3mm is maintained from sprocket to frame. Then we can assume that the switch is installed correctly.
- you need to set the minimum speed, that is, behind the chain stands on the largest star, and in front on the smallest.
- slightly loosen the cable tension and turn the screw L until there is a 1mm gap between the chain and the frame
- firmly fix the cable by inserting it into a special groove.
- we set the highest speed
- adjustable with screw H the gap between the chain and the inner side of the frame
- we check the performance
- if the switching is tight, then we adjust with screws to the desired state
- After all the manipulations, the bike should be washed and all parts (chain, sprockets, etc.)
Steering wheel switches
The switches here are exactly the same as on the rear wheel. They are absolutely no different, and even located exactly the same.
Cables and shirts
The cables do not differ from the derailleur on the rear in that they can be slightly shorter, or even slightly thinner. And shirts are also divided into three types, and each shirt has its own cable.
Useful Tips for Using Derailleurs on Your Bicycle
Of course, breakdowns and adjustments can be avoided if all the rules are carefully followed.
- wash the bike and its parts as often as possible, and then dry it thoroughly, since dirt and corrosion are the main enemies of metal products
- lubricate all parts with machine oil or grease (imported products do not cope very well, and often do harm)
- climb on your own to repair mechanisms only in extreme cases, since inexperience can only aggravate the situation, so it is better to ask professionals or friends for help.
In conclusion, I would like to say that you can fix any thing yourself if you do everything correctly, following all the tips listed above. Or even start monitoring its condition from the very moment of purchase. And then you don’t have to fork out for new parts, which, moreover, cost 2 times more than the bike itself.
Why the gear shifts poorly on a bike
As usual, entry-level bicycles are appropriately equipped with the transmission of the most inexpensive groups. When gears shift poorly and jam, owners of these bikes say what to expect from inexpensive components. Those who have purchased a much more expensive bike are very much surprised when, after a while, they also have problems with shifting.
Nobody wants to say that there is no difference between the top-end and the initial components, just the reasons for the fuzzy operation of the switches do not depend so much on their class as on their state and correct configuration. Why the gear shifts poorly on a bicycle?
Reasons for poor gear shifting. Cables and shirts
The most common cause of poor shifting, especially in inexperienced cyclists, is in dire condition for some bike enthusiasts. Inspect the sections of the cables not hidden by the shirt and click the shifters to expose the hidden part. There should be no scoring or protruding threads on the cables. If they are, then the cables and maybe shirts should be changed immediately.
To inspect the cable completely, you need to unclench the aluminum cap with pliers, which protects the cable from loosening and unscrew the bolt that secures the cable to the rear derailleur.
Release the jacket from the stops and carefully remove it from the cable. The other end of the cable can be left in the slot in the shifters. When the cable is completely exposed, inspect it again for thread scuffs and abrasions.
Wipe it down with a rag with WD-40.
If the shirts are in order, then they can be used further. To clean them of the dirt that has accumulated there, fill them with WD-40, and wiggle there with a rope.
You need to know that cables and shirts are not lubricated, especially with thick greases, otherwise after a while a mixture of grease and dirt will form in the shirts. You can spray it with a light spray lubricant, but it will quickly evaporate and there will be little sense. There are Teflon-coated cables, they slide better, are more expensive, and Teflon in friction areas wears out quickly.
It so happens that when the rear derailleurs are perfectly tuned, the speeds do not switch clearly, even with good condition of the cables and shirts. The reason may be a bent cock during careless transportation of the bike or from a blow.
If you have followed all the adjustment procedures and still cannot achieve a clear shift, inspect the cock. If it is crooked, then it must be leveled, but do not overdo it, as aluminum gives microcracks.
There are many ways to align it, but that’s in another article.
Rear derailleur play
Inspect the rear derailleur and, where the cable enters, move it with your hand from you, from towards you. Ideally, there should be no backlash at all, but if it is small, then it’s okay, especially on inexpensive groups of transmission components.
During operation, this backlash gradually increases, and when switching, there is a delay in the transition to another star, indistinctness, etc.
As a rule, the cause of poor gear shifting is a set of the problems described above. All together, a little bit, they give a negative result, you just need to regularly take care of the bike.
How to adjust the rear and front derailleurs on your bike photos and videos
Speed switches are actively used when riding both mountain and city bikes. Much depends on their quality work: the pleasure of cycling, the quality of the ride and even your safety. Before each cycling season, this mechanism should be checked and, if necessary, correctly adjusted.
What parts help to adjust the speed switches
The multi-speed mountain bike or city bike is equipped with several gears and offers new possibilities. It is much easier to conquer peaks, ride on irregularities, even perform various tricks on it. To enjoy cycling, you need to set the speed switch correctly.
Those who first decided to understand the switch mechanism on their own should first familiarize themselves with the details of the transmission and their functions.
Knowledge of the structure of modern bicycles helps to properly set up gear shifting
We will not dwell on each part of the bike in detail. Let’s consider just some of the elements that make up the transmission.
- the front derailleur assists the chain in guiding the chainring. Attaches to the frame near the pedals;
- the system is part of the front derailleur. It also consists of stars, different in diameter and number of teeth, which are attached to the connecting rods with special bolts;
The front derailleur is in the pedal area
Rear derailleur located on the rear wheel
chain. part of the transmission, which must be periodically lubricated with special oils and washed;
The bike chain is an important part of the drivetrain
shifters (or shifters). a device with which the cyclist controls gearshift. Pressing the lever changes the cable tension, as a result of which the speed changes. It is mounted on the steering wheel, near the handles. The shifter at the right handle is responsible for the rear derailleur, on the left. for the front. There are bicycles with one right shifter;
Shifters are mounted on the handlebars and are responsible for gear shifting
The transmission cable connects the shifter to the derailleur
The work of the rear and front derailleur is as follows: if the cable is pulled, the derailleur frame moves the chain to higher sprockets. If, on the contrary, weaken the cable, then the frame will throw the chain onto smaller stars.
The speeds are switched with the help of shifters (coins) located on the steering wheel. The rear derailleur is adjustable with the right shifter. Thus, the chain jumps between the rear sprockets. And the front derailleur is adjustable with a shifter on the left side. So the chain jumps among the chainrings.
The principle of operation of the speed switch. video. Gear shift types
Before making any adjustments, determine what kind of gear shift your bike has. There are 3 main types of switches.
Internal gear shifting for mountain bike
The basis of this design is planetary bushings. This mechanism does not use cassettes. The transmission includes only 2 stars: front and rear. The whole mechanism is hidden inside. There is usually no front derailleur either.
All elements of the speed switch are hidden in the body
This mechanism is often found on road bikes, pleasure bikes, folding bicycles and city bikes. The system itself is located inside the rear planetary hub. This type of shifter can be seen, for example, on the Forward Surf city bike (3 gears).
External shifting on a speed bike
The outer type belongs to most multi-speed bicycles. It is used on both mountain and city walking models. The mechanism is made up of gear shifters and stars that form a cassette or system. Variable speed with rear and front derailleurs.
External gear shift elements. derailleur and cassette
This type of gear shifting can be seen on both the Forward Dortmund city bike (7 speeds) and the Forward Agris mountain bike (24 speeds). You can customize this switch yourself by examining the mechanism.
Bicycle chassis design, principles of operation. video. Combined mechanism
The combined type is a combination of external and internal mechanisms. It attaches to the bike’s rear wheel hub.
The combo derailleur is a hybrid of the external and internal types of bike shifting.
This mechanism is extremely rare, since it has collected all the negative aspects of both external and internal gearshift systems. It is configured only by a professional.
In the modern world, there are many companies that create equipment for bicycles. The best quality models are made by corporations such as Shimano (Japan) and Sram (America), producing entire lines of derailleurs.
Devices for professionals:
Sports bike lines:
Sram ESP 7.0 derailleur specially designed for sports bikes
Hobbyist Switch Line:
There is no fundamental difference in the adjustment and operation of different switch lines from the same company. For example, different Shimano derailleur groups work the same and are interchangeable. Let’s say that the drive of eight-speed Alivio, Altus, Acera switches can be equipped with nine-speed Deore, Deore XT, Deore LX, XTR systems and vice versa.
The difference between the Shimano line is video. What can affect the quality of the switches
It is important to find out what caused the problem.
This defect is regulated by a drum on a shifter.
If the part is damaged, it must be replaced.
Changing the cable on the bike. video. Parallelogram spring problems
For better operation of the return spring, you need to wash it. Then lubricate after cleaning.
Rooster bent or broke
If the foot of the rear derailleur is oblique, then the mount is bent. You can fix this defect yourself.
Deformation of the switch
A common cause of such a breakdown is a blow from a bicycle. Usually the rear derailleur suffers, the front derailleur is very difficult to bend. After a breakdown, it is worth checking which parts are broken.
Changing bike transmission parts. video. How to adjust the rear derailleur
The rear derailleur is a machine that transfers the chain from one sprocket of the rear wheel to another. Today, the vast majority of high-speed bicycles are equipped with such a switch.
Most high-speed bikes are equipped with a rear derailleur
The rear derailleur consists of the following elements.
Setting the rear derailleur is needed if the mechanism is out of order, the chain jumps over the necessary stars, the speed does not switch, a grinding or loud sounds are heard. You can configure the mechanism and debug its work yourself. You will need a Phillips screwdriver and a hex wrench
First, make sure the derailleur is vertical and parallel to the bike. If everything is in order, you can proceed to the setup. For convenience, turn the bike upside down, placing it on the saddle and handlebar, this will give access to the switch itself and the adjustment screws.
First, lower the chain to the smallest sprocket. Do this with the shifter on the right handlebar of the bike, it is she who is responsible for the rear derailleur.
Use the right shifter to lower the chain
Loosen the screw holding the cable. This is done in order to unlock the switch.
Loosen the screw holding the cable
Prepare a screwdriver and find the screw with the Latin letter H.
Screw H limits top gear
Move the switch so that the sprockets on which the chain lies (one star on the cassette, two stars on the switch) are in the same plane, that is, they form one line.
All 3 stars must lie in the same plane
Take the cable with your hand. It must be pulled out as much as possible and fixed by tightening the screw.
We pull off the cable by hand and fix the screw
Check if the switch is working properly. If it does not go well on large stars, turn the thumbscrew counterclockwise, pulling the cable.
Adjust the tension of the cable by turning the lamb
Adjusting the switch position
Change the position of the derailleur so that the largest sprocket in the cassette lies in the same plane with the derailleur foot, forming a straight line with it.
Adjust until the frame and the largest star form one line
Setting the rear derailleur. video. Front derailleur adjustment
The front derailleur is less common than the rear derailleur. Bicycles with this device are cheaper. The front derailleur moves the chain to the stars of the system. Moving from side to side, he pushes the chain to the next star.
Front derailleur device
Front derailleur device.
The main problem with the front derailleur is that the chain hits the frame when driving. You can fix this problem yourself.
Setting the correct operation of the mechanism
Lowering the screw holding the cable
Take a screwdriver, find screw L. Move the frame so that the distance from its inner part to the chain is about 4 mm.
We adjust the correct position of the frame, for this we turn the screw L
Reattach the cable. To do this, tighten it with your fingers and tighten the screw that presses against the cable.
Hold the cable with your hand and fix the screw
We stretch the cable by turning the lamb counterclockwise
Move to the third star. If the chain touches the frame, use a screwdriver to adjust screw H. It is necessary to increase the gap by moving the frame outward.
We adjust the frame with screw H
Troubleshooting the front derailleur. video. How to change gears on any bike from Merida to ladies
To ride easily and comfortably with less effort, you need to switch gears correctly.
How to switch speeds correctly. video
By doing derailleur maintenance before every cycling season, transmission problems can be minimized. It is very unpleasant when the mechanism fails along the way. And adjusting the speed switch yourself and troubleshooting is easy even for a beginner.