Adjusting the rear speeds on the bike

How to Properly Adjust Bicycle Shifting

How to set up your bike’s derailleurs

Every cyclist sooner or later faces the problem of poor gear shifting on a bicycle.

There may be several reasons for this. damaged cables or dirty shirts, a stretched chain, poorly tuned front or rear derailleurs. It is the latter circumstance that most critically affects the quality of gear shifting on a bicycle and can turn your ride into a continuous torment.

Many beginners rely on experienced mechanics for this procedure. This is the correct approach. But over time, you realize that you need to learn how to independently make the specified setting. This will not only help to save a certain amount of money on the services of a bicycle mechanic, but will allow you to independently, at any time, adjust the speeds, ensuring the perfect gear shifting of the bicycle throughout the entire trip. This text provides specific steps that even a beginner cyclist can follow to adjust the speed of his bike on his own.

Rear derailleur setting.

The first thing to start with the adjustment is an external examination of the rear overhang. It is necessary to make sure that the gearshift cable is securely fastened and supplied, its integrity, cleanliness and no wear of the upper and lower derailleur rollers. And also, the flatness of the foot, which during the operation of the bicycle can deform when falling.

It is very easy to check the foot evenness. you need to look at the rear of the derailleur and make sure that the corresponding cassette or ratchet sprocket, as well as the upper and lower roller of the derailleur, are on the same mowing line perpendicular to the ground. If all of the above conditions are met, you can safely proceed to setting.

It is necessary to set the chain to the minimum rear sprocket, correspondingly turning on the maximum reverse speed on the bike. To carry out the adjustment, both the front and rear cross-overs have two adjusting screws on their body, denoted by the letters H and L (High and Low, respectively). Since at the beginning of the adjustment, the chain was set to the maximum gear at the rear, for adjustment you need exactly the screw with the letter H, which is responsible for adjusting the high speeds. By rotating it clockwise or counterclockwise, they achieve such a position of the switch foot so that both of its rollers stand strictly on the same mowing line with the smallest back sprocket. After that, it is necessary to engage the minimum reverse gear, in which the chain is on the largest sprocket at the back. And with another screw, which is designated with the letter L, make an identical adjustment before aligning the rollers with a large sprocket.

Sometimes a situation arises when, after correct and careful tuning and adjustment of the rear derailleur, a problem arises when shifting into high or low gears is poor. This is due to a strong or weak tension in the gear shift cable. This adjustment can be done in two ways. a special regulator on the rear derailleur, or a regulator on the gear shift knob (shifter). Which of the options is used on a particular bike depends on the level of equipment set by the manufacturer. If the chain is thrown poorly into lower gears, the tension of the cable should be increased, and if the chain is dropped to higher gears, on the contrary, it should be reduced.

There is another adjustment option on the middle and high level rear crossbars. distance of the idler roller (top) to the cassette stars (chain tensioner adjustment). It is produced as follows. The chain is installed on the largest sprocket at the back and the largest at the front. In this position, the rear derailleur foot will be pulled to the maximum. And with the adjusting screw, you need to achieve a distance of approximately 5mm from the top roller to the sprocket teeth. It is at this distance that the smoothest and most precise gear changes are made. It is not worth reducing it, as there may be a risk of grazing the roller by the sprocket teeth and damage it.

Front derailleur setting.

adjusting, rear, speeds, bike

Before adjusting the front bumper, the first step is to make sure it is correctly positioned on the bike frame. For beginners, there are two recommendations. The first is to make sure that when the largest chainring is engaged in the front, its teeth are a short distance from the bend of the derailleur frame, as well as at the same distance from it. At the same time, in no case should they touch the frame or, on the contrary, be far from it.

The second is the parallelism of the switch frame to all the stars in the horizontal plane. That is, if you look at the switch from above, then its frame should be parallel to the stars of the system.

You need to start the adjustment by setting the chain to the minimum front and maximum rear sprocket. Next, you need to unscrew the bolt that fixes the cable to the switch housing. After that, it will take its natural position and you can proceed directly to the setting. Turning the screw marked L (Low) in different directions, you need to set the gap between the chain and the switch frame in the region of 1-2 mm. It is this distance that will ensure perfect shifting, and also eliminate the possibility of chain friction on the derailleur frame during driving. After that, it is necessary to fix the shift cable with a slight interference, making sure that it lies in the required groove in the clamping area. With the chain set to the maximum chainring and minimum sprocket, use the adjusting screw marked H to adjust the same way until the minimum clearance is found between the chain on the large chainring and the derailleur frame. If, after carrying out the above procedure, difficulties arise with the inclusion of low or high forward speeds, it is worth adjusting the tension of the shift cable, similar to setting the rear derailleur.

Having mastered both types of speed adjustment on a bicycle as quickly as possible, you will protect yourself from unpleasant surprises that may arise during the ride, having the opportunity to make the necessary adjustments at any time, spending a minimum of time and effort.

How to adjust bike speeds?

There are two gear selectors on modern models of these vehicles. front and back. Usually, the adjustment begins with the latter, but there are also cases when it is necessary to adjust only one crossover.

adjusting, rear, speeds, bike

Possible causes of indistinct / incorrect speed switching

Before talking about how to adjust the speeds on a bike, let’s talk about the possible causes of such defects:

Setting up the rear derailleur

First of all, you need to put the chain on the smallest sprocket of the cassette. This can be done using the right shifter. it is this detail that directly affects the rear derailleur on a bicycle. To release the cable, you need to unscrew the screw that fixes its position. The screw marked H must be unscrewed with a screwdriver so that the smallest sprocket is in the same plane with the sprockets in the foot. Next, the cable must be pulled and secured with a screw.

After that, you should definitely check the work of the transfer. If the chain does not switch to large rollers (stars), then the cable must be tightened even more, using the drum already on the shifter or on the transfer. The chain is moved to the largest roller and the position of the switch is adjusted with the screw L. Ideally, the cross-over should not be able to hit the knitting needles, that is, the foot and the star should be in the same plane.

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How to fix defects?

Every speed bike must have an attentive owner. That is, all the details. cable, sprockets and switches. must be lubricated with special agents. lubricants.

If the cable is stretched, it can be slightly tightened. In the event that it has already broken, it should be immediately replaced with a new one. Algorithm of actions:

If the spring does not work well enough, then it must be rinsed with water and lubricated.

Rooster deformation can be seen not only in special bike shops. A bent cock is visible if you place the rear derailleur frame obliquely. In case of slight deformation, it can be leveled independently by pulling it out until the hind foot is level. However, remember that this is only a temporary measure. It is best to replace a deformed part with a new one. The same goes for the bent crossover.

How do I adjust my bike speeds? How to adjust bike speeds?

Despite the fact that the derailleur has a primitive mechanical design, adjusting it can be quite difficult for cycling enthusiasts. Read this article to learn how to set your bike speeds and learn how to use the derailleur correctly.

Let’s define the terminology

Before talking about such a concept as adjusting the speed of a bicycle, you need to understand the basic definitions so that even a novice cyclist understands what is at stake.

The speed selector is sometimes referred to as a toggle. It is an indispensable component of any modern speed bike. It looks like a rectangular spring mechanism with a frame (or foot) attached to it. When it comes to the shifter, it is impossible to ignore the shifter. a device that is designed to control the transfer by adjusting the cable tension. Usually this important part is attached directly to the handlebars. But there are bicycle models where the shifter is located on the down tube of the front triangle of the frame.

Every seasoned cyclist knows what a rooster, cassette and speed bike system is. For the rest, we will give definitions to these terms:

How to adjust the speeds on a bike without fixing screws? The two notorious switches marked H and L are right on the cross-over. First. Hight. this is a stop screw for adjusting large gears (or small sprockets or gears). L (Low) adjusts small gears. Their location may vary on different models.

Adjusting the front derailleur

This algorithm of actions will tell you how to adjust the speed on the bike by setting the front overhaul:

After reading this article, you will know for sure the answer to the question of how to set the speeds on your bike. The main thing. follow the above steps, and the process of adjusting the speed switch will not seem so difficult to you.

Front derailleur

The front derailleur usually has more travel and requires less adjustment, so they usually start with that. In addition, the readjustment here requires less precision and it is easier to repeat it after the rear.


Speed ​​switches are one of the most complex in terms of design, but rather unloaded in terms of toolkit elements of a bicycle. In order to set everything up, you only need a few things:

  • screwdriver;
  • pliers;
  • key for 9 or a set of hexagons (depending on the manufacturer);
  • replaceable cables and shirts (if replacement is needed).


The front derailleur is adjusted as follows:

  • Position the derailleur so that the rear is the largest star and the front is the smallest.
  • Unscrew the cable.
  • Adjust the position of the frame with the screw limiting the lower gears. It must be located a maximum of 3 mm further from the chain.
  • Stretch the cable a little.
  • Switch the speed to the middle of the stars.
  • Check if the chain is touching the outer frame or not. If the mechanism does not function correctly after performing all the actions, tighten the cable even more.
  • Set the front derailleur to the smallest of the stars.

At the end, it is important to check if the gear changes are easy. If the mechanism does not work, you need to adjust the screw that limits high gears.

How to adjust the speed switch on a bike

It often happens that either the speeds on the bike are not switched clearly, or some new transmission elements have been installed. In this case, you will need to adjust the speed switch and it is quite possible to do this work on your own, without contacting specialized workshops.

Setting up the gear selector only looks complicated but can be done on your own. Beginners are scared off by this process, and quite rightly, by the complexity of the whole complex of works. Indeed, when setting up, a flaw can be identified that is associated with the frame, and with the stars, and with the system, and with the bushings.

In general, the adjustment operation is one of the most dependent on the correct assembly and tuning of almost the entire bike. It requires serious attention to itself. Despite all the difficulties, the adjustment must be carried out constantly and do not forget about it, because the quality of skiing primarily depends on the drive mechanism, and repairs will be required much less often.

Rear derailleur

Initial checks on a rear bicycle derailleur begin with the derailleur mechanism. complex than the front, it can hide more problems in itself than can be corrected with a tweak:

  • The rooster is a special mount, and, being usually a separate part from the frame, the rooster is damaged by falls and even serious loads, therefore it is very important to check its parallelism to the frame and, in general, its integrity.
  • Recoil spring. its defects are often perceived as problems with the cable jacket, as they look the same: switching on the loosening of the cable becomes problematic. Springs are usually changed along with the entire device.
  • The cable feed is a secondary test, on many derailleurs, especially budget Shimano derailleurs, the cable runs into the rear derailleur from the back, creating a kind of loop. It is on it that damage usually appears, since this point is easily damaged when falling or driving on the grass.

Features and varieties

The Shimano product line includes a large number of derailleur categories depending on their purpose:

How to adjust bike speeds

Sometimes it is better to delegate the adjustment of bicycle parts to professionals. And if the question arose about adjusting the speeds, then the beginner has a direct path to the bike workshop. But if you like to figure it out on your own, this article is for you.

The rear wheel stand and tools come in handy to adjust the gearshift more conveniently. Prepare a set of wrenches for different nuts, flat and Phillips screwdrivers for adjusting screws. You will also need a set of L-shaped hexagons.

The chain must be installed on the smallest stars both front and rear, then carefully remove dirt and dust from the entire surface. It is also necessary to get rid of the old grease, which can stick to some parts. Clean all rotating parts thoroughly.

How to adjust the screws on a bicycle

If you just took the bike out of the closet, and sent it there in a completely working order, do not touch anything. All the mechanics of famous bike brands advise changing all cables once a season. If full speed control is required, the shift cables and shift jackets should be replaced. It is necessary to unscrew the nut that holds the shifter drive cable and remove the protective cap from the cable.

Often on the shifters and the derailleur and the cable tensioner there is a nut with the help of it and tighten the cable. It must be carefully removed from the shirt cable. New ones can be cut from them. After pulling the cable out of the shirt, it must be cleaned of dirt, removed from the shifter and replaced with a new one. Then new shirts with longitudinal weave and new tips are installed. Older shirts may need to be trimmed or shortened or lengthened.

Now the chain needs to be switched to a large sprocket and reset. If this works, check the shifting of all rear gears, a successful shift should be the result of your setup. If shifting fails, adjust shifting by tightening or loosening the shifter cable with the adjustment nuts. Try not to overtighten them, smoothness is important here.

Look from behind at the switch position on the smallest and largest stars. The correct position of the wheels can be found with a switch. Screw marked Lo or. helps to adjust the position of the rear derailleur so that the position of the largest gear is in the same plane as the derailleur rollers. When adjusting the position with a screw marked Hi or, you need to set the arrangement of the stars in one plane. the smallest and the gearshift wheel.

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Do the same for the front derailleur. Check the operation of the switch after replacing the cable and jackets with new ones. Place the cable on the smallest chainring and tighten it. Then try switching to 2 and 3. The switch is adjusted by pulling on the cable with the adjustment nut located on the shifter.

If necessary, loosen or tighten the cable using the fixing nut on the derailleur.

How the switches work

Using the handle and shifter, the cyclist activates the required speed. In a certain position of the handle, the cable is pulled. As a result of this tension, the frame is thrown onto larger sprockets; when the cable is loosened, it is not thrown onto small sprockets. As mentioned above, you can start setting up your bike from the rear derailleur. Procedure for adjusting the rear derailleur:

  • select the second star in the front block, and the smallest in the rear one and set the switch chain on them;
  • The bike’s rear derailleur system has two bolts that act as stops. One is abbreviated as H, and on the other. L. These two bolts are used to adjust the high and low gears on the sprockets. If during the adjustment process any extraneous sounds occur, you can get rid of them with the help of the latch;
  • check the tension of the cable and if the tension does not correspond to the required one, use the regulator located on the shifter;
  • Test the switching quality. If the switching occurs smoothly, no extraneous sounds are heard, then you did everything right.

Rear derailleur

The gear selector is an important part of a multi-speed bike. Thanks to this component, it becomes possible to move in extreme conditions, which include upwind movement, ascents, poor road quality. The transmission unit must cope with all these problems. The quality of the ride and the safety of the cyclist depend on the fine-tuned operation of the speed switch. This skill is very useful, and every bike owner should learn how to independently adjust the gear shifter. Every cyclist can make adjustments to the bike’s gear shifters on their own. You need to study the theory in detail by reading the instructions, or using the advice of experienced bike owners.

How To Index Your Gears. Adjusting Your Rear Derailleur

Before setting the derailleur, the rear derailleur must be adjusted. Placing the bike in the correct position (wheels up) will greatly facilitate the entire adjustment process. So, all the necessary details will be in plain sight, and it will be much easier to get to them.

Reasons for poor gear shifting:

  • physical defects of the switch parts;
  • contamination of parts. To prevent this from happening, the components of the transmission unit must be periodically cleaned of dirt, dust and old grease;
  • worn out cable with elements of damage. Such a part requires replacement;
  • damage to the cock.

If you observe damage, deformation and wear of the constituent parts, they must be replaced as they are practically irreparable.

If all parts are OK, adjust the switch. What is the speed selector made of? The components of the speed switch are as follows:

  • The handle for shifting the speeds, located on the steering wheel;
  • A shifter that attaches to the handlebars near the handles. Handles and a cable are attached to the shifter. It is with the participation of the cable that the impulse is transmitted from the shifter to the stars;
  • Cassette, which includes stars of different sizes;
  • front fixing mount;
  • rear derailleur, whose main function is to transfer the chain to the necessary sprockets.

What to do if you can’t adjust the bike’s rear derailleur

There are several methods for solving this issue. But if the standard tuning instruction did not work, to tune the rear derailleur you need to:

  • dismantle the chain, remove the cable;
  • move the switch to the chain position to the smallest star;
  • use adjusting bolts (this way you can tighten the cable);
  • set the adjusting bolt H to the extreme position;
  • move the part called the parallelogram to the big star and adjust the position of the bolt L.

The regulator is fixed with bolts. It must be set to the extreme position. After that, the chain must be displaced in this order: the front cassette is the largest star in diameter, the rear one, on the contrary, is the smallest.

How to properly adjust the rear and front derailleurs on a bicycle: photo and description of the process

Despite the fact that the bicycle was invented a long time ago and, it would seem, should have been out of date for a long time, but this two-wheeled vehicle is gaining more and more popularity every year. Cycling enthusiasts prefer this type of transport due to its convenience, ease of operation, environmental safety and practicality. Not only ordinary bicycles are very popular, but also mountain, track bikes, in which modern innovative technologies are involved. In order for the owners to enjoy cycling, they need to take care of it and monitor the condition of all parts and assemblies. If, in the process of cycling, you hear extraneous sounds, creaking, knocking and twitching during gear shifting, it’s time to pay attention to such a detail as the gear selector.

Bicycle front derailleur

The transition to the setting of this mechanism is possible only when the rear derailleur is set. This feature is important to take into account before starting work. The figure shows the switch (round, black).

Leave the chain on the middle sprocket of the front block and place it on the large sprocket in the rear block. If chain friction is observed, re-engage adjuster L. To adjust stop H, the chain moves to the largest sprocket at the front and smallest at the back. The adjuster will help to position the chain in the optimal position without friction and excessive tension on the chain. At the end of the work, be sure to check the quality of its implementation.

Correct installation of the front derailleur

You can start the front derailleur setting only after adjusting the rear derailleur. Installation is the initial step in adjusting the speed switch. It’s very important to do it right.

  • before installing the switch, it is necessary to inspect the condition of the constituent parts and, if necessary, clean them from dirt and lubricate.
  • The next step is to adjust the location of the front derailleur. On the frame, it should be located along the pipe under the saddle.
  • Set the steering angle parallel to the drive sprocket on the front cassette of the transmission unit.
  • Next, you need to adjust the gap between the underside of the derailleur frame and the upper mowing line of the teeth of the large gear. The gap should be minimal.
  • Adjust the cable tension.
  • Place the chain close to the inside of the frame.

It is also worth paying attention to setting up the chain. The bike chain is a very important element, with the help of which the impulse is transmitted from one chainring to another and the adjustment process takes place. The technical condition of the circuit is of great importance for the operation of the entire system. If, for some reason, the bicycle chain stretches or deforms, this cannot but adversely affect the operation of the entire transmission unit. To prevent this from happening, the chain must be periodically removed and cleaned, and then set the correct position. There are lock and lockless models of bicycle chains. They differ in the way they are connected. To remove the locking chain, it is enough to find the link with the lock and disconnect it with a screwdriver. The lockless bicycle chain is disconnected using a squeeze. This tool helps to push the link axle out and make the connector. If it skews for some reason, this can adversely affect the gearshift process.

One of the best manufacturers of bicycle parts, including derailleurs, is the Japanese company Shimano, which has a proven track record of producing products in which Japanese quality is combined with budget and price. Shimano derailleurs are suitable for all types of bicycles. Shimano derailleurs are installed on both regular touring bicycles and mountain and track bikes with gearboxes up to 33 speeds.

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Another recognized market leader is Sram. The products of this company are used on bicycles of the city bike category, as well as on sports bicycles. Sram products are of good quality and affordable price for cycling enthusiasts.

Every bicycle owner who prefers this type of transport to others is obliged to understand how to switch its speeds. It is believed that the more speeds a bike has, the better it is. But in fact, speed only allows you to improve the quality of maneuvering and squeeze the maximum out of the bike‘s capabilities, so then everything depends on the dynamic efforts of the person riding the bike. Conventional bicycles have a simpler design compared to high-speed ones. With such a bike there is less hassle, but it also has fewer possibilities. In the transmission unit of such bicycles there are only two stars: one large and one small. Multi-speed bikes, which have gained popularity in recent years, have two sets of sprockets in their transmission units: front and rear. Each cassette consists of stars of different sizes. To switch gears correctly, you need to remember a few basic rules:

  • If your bike is not equipped with a planetary hub, you only need to change speeds on it while driving, otherwise there is a danger of damage to the bike.
  • During gear shifting, it is not necessary to apply significant dynamic forces, in order to eliminate the danger of a burst of flowers, it is advisable to change gears sequentially, without making sharp jerks.

Rear Shift Adjustment

The standard and common drivetrain, such as on a mountain bike, is a chainring at the bottom bracket and at the drive wheel with appropriate derailleurs. It is necessary to start tuning the system from the rear sector of the gearshift system.

  • setting the chain travel limit on the cassette;
  • overdrive adjustment;
  • changing the position of the tensioner.

It is necessary to adjust the travel limit to prevent the chain from falling off the sprockets. This procedure is performed by tightening the L and H screws with the high and low gear adjusters. You need to turn the screws until the rear sprockets corresponding to them lie in the same plane with the limit rollers. Step by step, this process looks like this:

  • Set the extreme position on the stars: the front is the largest, the back is the smallest.
  • Loosen the rope.
  • Turn the screw H to achieve complete coincidence of the rollers and the small sprocket in the same plane.
  • Return the cable to the derailleur and set the opposite position: the front is the smallest star, the back is the largest star.
  • Rotate the L adjuster until the stops are aligned with the large rear sprocket in the same plane.

Chain transfer quality is the most important characteristic of transmission performance. Accuracy and transition speed are controlled by the following mechanism:

  • Set the system to the position of the small star in the front and small in the back.
  • Rotate the cable adjustment drum, tightened to the stop at the beginning of work.
  • The correct position of the drum is determined and, accordingly, the degree of tension of the drive.

How to find this optimal position? With a weak cable tension, the chain will not jump well to large stars. An overtightened drive cable results in poor transition to small (higher) stars, accompanied by a sharp clang. To strengthen or loosen the tension, we twist the drum counterclockwise or clockwise. Don’t forget we’re talking about the rear derailleur.

Well, the last step in adjusting the rear speeds on a bicycle is adjusting the position of the tensioner. In the front we activate the smallest one, and in the back the lowest one and rotate the chain tension screw. The distance between the deflection roller and the sprocket should be between 3.5. 4.5 mm. A vernier caliper will help to accurately measure this distance.

adjusting, rear, speeds, bike

How to properly adjust your bike’s gear shifting

The gearshift system is one of the most vulnerable parts of a bike. Transmission components are susceptible to wear and tear and imbalance, which requires repeated adjustments during operation. The main symptoms of speed mismatch are difficult shifting while driving and chain jumping over one or more sprockets.

If the above signs appeared suddenly, and the quality of all components of the transmission is not in doubt, then it is necessary to adjust the speeds in the rear and front sectors of the gear shift. It is not worth neglecting the adjustment, since over time the stars will experience increased wear, the chain will begin to fly off, and it will be completely inconvenient to ride. The procedure for setting the speeds on a bicycle is not difficult and can be done at home.

Preparing to set up the transmission

It is wrong to start adjusting the gearshift system right away. The bike has been on the road for some time, therefore, there is a certain amount of adhered dust on the chain. Be sure to remove all the dirt from it, lubricate the rollers, sprocket points and the switches themselves. Sometimes problems with a tight transition from one speed to another lie in the dirty chain. If, after cleaning and lightly lubricating, the problem is resolved, then you do not need to adjust the switches.

Next, pay attention to the drive cables: they must be flat, without bends. Otherwise, they will have to be changed. Inaccurate shifting and jumps may be due to faulty cable.

Another preparatory procedure is to inspect the cock near the rear derailleur. The rooster must be in an upright position and strictly in the same plane with the rollers. You can align it, but it is better to change it to a new one.

As for the bike’s front cassette derailleur, here you need to make sure that the inner frame is parallel to the chain travel. The distance between the largest sprocket and the outer frame of the switching device must be within 2-3 mm.

Everything is all right, and the speeds keep turning on badly? Then it’s time to adjust the transmission. We loosen the tension of the cable to the maximum, tighten the drums on the switch until they stop. After adjustment, the system will work more accurately, and there will also be a necessary margin in case of lengthening the drive cable.

Adjusting the Limitations and Quality of Chain Hopping on the Front Derailleur

The next part of tweaking the transmission is adjusting the front derailleur. The work includes debugging the accuracy of the chain travel limits using the H and L-screws, as well as the speed of the chain transition when gears are engaged.

If it was correct to start from the rear with the high gear limiter, then here first the position of the roller is adjusted from the side of the lower gears:

  • The chain is transferred to the position of the lowest in front, highest in the back.
  • The cable is detached from the derailleur.
  • By turning screw L, the smallest possible distance of the chain from the inner frame is achieved.
  • The cable is put on and pulled by the drum adjuster.

Setting the correct limiting with screw H differs from the L-setting by reversing the chain position on the stars (smallest in front and largest at the back) and approaching the chain to the outer frame of the derailleur.

How to adjust the accuracy and response speed of the front derailer:

  • We turn on the top gear from the front.
  • We consistently transfer to lower gears.
  • We tighten the cable if the chain is tight and slow.
  • We reach the lowest star and switch in reverse order.
  • We loosen the tension by turning the drum if the chain does not go to higher gears.

When tuning, you should achieve fast operation of the switch on all stars. Initial position of the chain at the rear: when checking for insufficient tension, the smallest sprocket, and for excessive tension, the largest sprocket.

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It is on this simple principle that the front and rear parts of the transmission are debugged. Quality parts such as shimano rarely need adjustments and last a long time afterwards. In any case, it is quite possible to fix the imbalance problem with your own hands without going to the workshop.