Bicycle Rear Derailleur Adjustment
After we have eliminated all 5 possible problems with the rear derailleur, we can begin to configure it. I took a bike with a shimano rear derailleur and divided the whole setup into 8 steps:
On the shifter, we throw off to the highest speed (which corresponds to the smallest star on the block of led stars). We pedal so that the chain is on a small star. (now you understand why it is so convenient to work with the rack)
I do not show numbers on the shifter, but believe me the position of the indicator is on the “number” 9. Which corresponds to the smallest star on the cassette.
When adjusting the rear derailleur on the sprockets (front) the chain is best positioned where you use it most. This is usually the central star on a 3-star system.
Loosen the hexagon or bolt that holds the cable.
We twist it all the way, and then we return one turn back all the adjusting thumbs of the cable tension, which are located on the switch and on the shifter (sometimes there is only one adjustment screw on bicycles, most often it is on the switch, less often on the shifter).
In my case, the cable tension regulator is located only on the shifter. The photo shows how I twist the lamb.
We pull the cable with our hand (it is not necessary to pull with all our strength, the main thing is that it does not sag and be stretched along its entire length) and tighten the bolt holding the cable.
Align the center of the derailleur foot rollers with the center of the smallest chainring on the bike. Some people remove the chain for stages 5 and 6 to fine tune them. I do not see the need for this, you can not shoot, especially if you have a switch that is not of the top level, such as shimano tourney, acera or alivio.
HOW TO RIDE FAKIE / BACKWARDS ON A FIXIE
Actually, all this movement of the switch occurs using the adjusting screws with the letters “H” and “L”.
We turn the screw “H” with a screwdriver until the centers of the rollers on the foot of the switch and the small star coincide and go on to the next step.
In the photo, I showed a red line, by which you can see that the switch roller is under a small star on the cassette, which means that the extreme position is set correctly.
We switch on the shifter to the lowest speed (number 1), which corresponds to the largest driven star. We twist the pedals so that the chain goes to the extreme sprocket. And also align the center of the presser foot rollers with the center of the largest sprocket. All this alignment takes place with the screw “L”.
On the shifter, the indicator for switching the speed to number 1, if there are no numbers to the most extreme position, which should correspond to the largest star on the cassette.
Essentially, the “H” and “L” screws act as end stops for your derailleur, which keeps the chain from flying off while driving and keeps you alive.
We drop again at the highest speed. Do not forget to pedal. The chain should be on the smallest star. Next, switch to one speed and turn the pedals, if the chain does not jump or does not jump right away, then you need to slightly unscrew the adjusting screw that adjusts the cable tension (it turns out we are pulling the cable).
Then again we check and switch from the highest speed one step lower (if an 8-speed cassette, then from 8 to 7 speed), if the switch happened immediately, congratulations you set the switch! You can check the remaining speeds will also easily and clearly switch both up and down.!
The chain should jump to the adjacent speed. In my case, this is a 9 speed cassette. Switching from 9 to 8.
Adjust the distance from the largest star to the derailleur roller. This distance should be about 4 mm, if the distance is greater, the switching clarity will be reduced. The adjusting screw on the switch is responsible for adjusting this gap. By unscrewing the screw, the distance decreases, screwing it in increases. tuning is done on the largest star corresponding to the number 1 on your shifter.
What you need to do before setting up work
Before adjusting and adjusting the rear sprocket, you need to inspect the rear sprockets for dirt and defects. If necessary, it is necessary to clean from dirt and lubricate all the components of the transmission mechanism. Sometimes it is enough to perform cleaning to make the switch function again in the previous mode.
For cleaning the mechanism from dirt and working off, special cleaning fluids are used, which clean all the elements of the mechanism. The cable is checked for integrity and freedom of movement, which must be cleaned and lubricated, or replaced with a new one. The bicycle chain is also lubricated, which is described in detail in another article. The rear cassette and the front system are cleared of dirt and clogging, and only after that you can proceed to setting.
When all the preliminary measures have been taken, it remains to adjust the rear derailleur, for which there is an instruction.
Steering wheel switches
If the shifter on the handlebars breaks, it will not be difficult to understand this, since the cable tension will immediately weaken, or it will simply stop pulling. Chasing expensive Sram, Shimano components in the hope that they will not work better is not worth it. For an ordinary inexpensive bike, the speed of gear changes and the weight of components are not as important as the maintainability and cheapness of replacement parts.
about setting the rear derailleur in a short
Reasons for the malfunction of the rear spreader
Design features and principle of operation of the device
The rear derailleur of different models (Shimano, Deore, Sram, SunRace, Acera, Tourney) has the same principle of operation. The main components of rear crossovers on high-speed bikes are:
- Fastening the entire mechanism to the cock. This fastener is a hole that is designed to be bolted to the bike.
- The shirt stop adjusts the tension. The rope is pulled or weakened by it. It is in these places that dirt accumulates or corrosion forms, which negatively affects the switching process.
- The guide is in the form of a kind of lever with a groove through which the cable passes to the fastening bolt. Some designs of mechanisms may not have guides, so the cable is immediately fixed from the stop with a bolted connection.
- Fixing bolt for securing the cable.
- Adjusting screw for installing the guide roller.
- The parallelogram is a movable structural mechanism of the switching device, which, when displaced, moves the foot with rollers in the corresponding direction, while performing a change in speeds.
- Screws L and H. They are designed to prevent the chain from falling off when changing speeds.
- The foot is a frame in which the rollers for passing the chain are placed.
- The guide roller is designed to guide the chain on the sprocket of the rear cassette. The main purpose of the device is a guide when changing speeds.
- Tensioner pulley, to which the chain is supplied from the front sprocket. Excessive chain slack is eliminated by this roller and spring.
The design features of the rear units are identical with only minor differences. The photo above shows how all the structural elements look like. The operating principle of the rear derailleurs is as simple as the design.
- To change the speed mode, you need to press the steering wheel adjuster.
- This adjuster is connected to the rear gear with a steel cable.
- The second end of the cable is fixed with a parallelogram through a bolted connection.
- When the cable is pulled, the parallelogram is displaced towards the larger star. When weakening. in the opposite direction, that is, to a smaller star.
- When the cable is loosened, the movement to the smaller star of the parallelogram is provided by the spring.
- When the position of the parallelogram is changed, the presser foot is displaced in the desired direction together with the rollers: guiding and tensioning.
- The tensioner pulley is spring-biased, thereby eliminating chain slack. The accuracy of gear shifting depends on this mechanism.
- The guide roller moves the chain towards the desired sprocket. The chain is fixed by small lugs on the star.
Why doesn’t a bicycle move backwards when you pedal back?
This is how the rear speed changers are arranged on high-speed bicycles, with the exception of planetary ones. Mechanisms with 6,7,8,9,10 and 11 speed systems are now on the market, but the principle of operation is the same for all.
How to adjust the high gear limiter
The screws L and H do not affect the adjustment process, they serve to prevent the chain from falling off the cassette stars. For the setup process to be successful, the chain must be positioned on the largest chainring in the front and the smallest at the back. Next, we carry out the following actions:
- The hex bolt that secures the cable to the parallelogram is unscrewed and released. The adjusting cuff, which is needed to fine-tune the length of the cable, must be fully tightened, both on the switch itself (not available on all models) and on the shifter on the handlebar.
- By turning screw H, you need to ensure that the derailleur rollers are located on the same imaginary line with the smallest sprocket (the purpose of this procedure is to prevent the chain from falling off the smaller sprocket).
- The shifter must be switched to the largest number (so that the chain is on the small sprocket). After that, you need to tighten and secure the cable.
- After it is fixed, switch the speed switches to 1. 1, on the system to the smallest sprocket, and on the cassette to the largest.
Clockwise rotation of the screw H contributes to the deflection of the frame towards the larger star along the radius, and against the smaller.
Front Derailleur Installation Procedure
What should be done before adjusting the front derailleur? Usually, the adjustment is preceded by the disassembly of the PPP and its removal for maintenance. It is very important to set the front derailleur clearly before performing the setup procedure.
Many cyclists ask the question of how to install the PPP on a bicycle by independent actions. Let’s analyze this algorithm point by point.
- The ideal position is when the guide frame in the area of the longitudinal axis is parallel to the front sprockets. It is better to dismantle the chain during installation.
- Achieving the minimum distance between the frame and the large star by aligning and bending the parallelogram.
- Determine the height according to which the clamp will fix the switch. Slightly tighten the clamp fixing bolt.
- The position of the frame axis is adjusted by turning the switch. In this case, the frame should become parallel to the front star system.
- We check the distance from the frame to the largest sprocket and the parallelism parameters. Tighten the clamp clamp.
- The installation is complete. We put on the chain and go to setting
PPP setting procedure
First, it is advisable to position the bike so that the rear wheel is raised. A regular ironing board is ideal for this.
We carry out clearly sequential steps of action.
- First, the lowest speed on the switch is set. In this case, the cable cannot be fixed on the cross-over. Using the shifter, pull the cable up to the stop with rotary movements clockwise. No need to tighten as much as possible.
- The rear derailleur is placed in the lowest speed position. As a result. the first speed on both stars.
- Adjust the L limiter, bringing the inner side of the frame closer to the chain. The described bolt rotates counterclockwise.
- The cable is mounted in the place of attachment to the PPP and tightened with pliers. We fix.
- Set the gear in front to the largest sprocket, and behind _ to the smallest.
- We pass to the limiter H. The outer side should be as close to the chain as possible. We adjust with rotational movements.
- Now set the speed to 5 on the rear derailleur. When pedaling, we change the speed of the PPS over the entire range.
- We set the speed 2 in front and by changing the position of the rear cross-over, we check the friction of the chain against the frame. In the presence of such a defect, adjustment is made by pulling the cable.
- We test the switch on a level and safe section of the roadway.
Differences between road derailleur setting and MTB
There is no difference in front derailleur settings on mountain bikes and road bikes. The only thing is that the road bike uses not 3 stars, but two stars in the system of stars, which makes the tuning faster.
If you have a dual system. You will also need to complete all the points, and in the 4th step there will be no adjustment of the central position, and the tension of the cable will be adjusted when switching to the 2nd star, where there will be an adjustment of the extreme position with the screw “H”.
Congratulations you have tuned the front derailleur, I also recommend checking if you have the correct chain length.
How to properly adjust the bike’s front derailleur?
It is generally not worth adjusting the front derailleur until the rear derailleur is configured. But before you tweak something, you need to thoroughly know how it works. Therefore, let’s try to understand the principle of its work.
We expose the extreme position of the frame using the bolt “H”
When setting the extreme position “H” we need to switch to the smallest star on the cassette, which corresponds to the largest number on the right shifter from 6 to 11, depending on how many speeds you have there. We put the chain on the third star (the largest star on the system) and turn the screw “H”. We adjust the frame so that the chain does not fly onto the connecting rod with a clearance pedal of 1 mm will be quite enough.
Checking the clarity of gear shifting.
Try to change gears and see if the chain goes to all stars.
often than not, the chain does not go from the second star to the first and clings to the switch frame. This is solved by unscrewing the “L” bolt (so that the switch frame moves towards the frame) one or two turns and everything should work perfectly.