Bicycle support. what functions does it perform
Bicycle calipers, or cars, are moving parts on gear derailleurs and disc brakes. Under the influence of a change in the tension of the cable, the calipers move, due to which the desired position of the chain or brake shoe is set.
There are three types of bicycle calipers:
- front derailleur. a machine with a fixed frame, driven by a cable, changes position and throws the chain over the sprockets;
- rear derailleur: part with frame and rollers, keeps the chain tension at a constant level when changing gear;
- brake: attached to the bike frame, are responsible for the movement of the brake pad in relation to the rotor (disc).
When changing gears, it is necessary to relieve the load on the pedals in advance, this will allow the chain to move more smoothly from one sprocket to another and reduce the load on the caliper. When scrolling the pedals back and while parking, you cannot switch speeds: this is fraught with breakdown of the mechanism.
The brake caliper works regardless of the speed of the bike and the applied pedal load. Its essence lies in the fact that when the tension of the cable changes, the parts along with the pads move (approach the disk) or diverge, moving away from it.
It is worth repeating once again: the technical condition of the calipers will extend the service life of the transmission, reduce brake wear, and therefore increase the safety of movement.
How to set up a node with your own hands
Do not tweak heavily worn and long-lasting budget parts (entry-level Shimano, for example). it will smooth out a little, but it will not solve the problem.
Front Derailleur Lever Setting:
- Place the machine in a position in which the chain should be evenly located on the large sprocket.
- Put the chain on a small star.
- Tighten the cable.
- Using the adjusting bolts, set the end positions of the frame.
Sprocket ratios. Part 2
Setting the end positions and the correct tension of the screws allows the chain to be pulled evenly when shifting gears in both directions. If the chain does not go well from low gear to high, loosen the adjusting screw L, and vice versa.
The adjustment of the rear derailleur is carried out by analogy with the front derailleur, although here you have to tinker longer due to the larger number of sprockets.
- Set the chain to the highest gear position (smallest sprocket).
- Loosen and then tighten the cable of the machine.
- The top sprocket must be completely in line with the guide roller (adjustable with screw H).
- Set the end point in the same way on the side of the lower gear. the large sprocket should converge in line with the guide roller (adjustment with screw L).
- By switching to other stars, determine where the tension setting is required. With the help of the adjusting bolt, achieve a quick and easy transfer to this sprocket.
The calipers may not perform well due to accumulated dirt, so they should be cleaned before adjusting.
How to adjust the disc brake caliper:
- The rotor engages in the pads. Loosen the assembly to the frame. If friction has decreased, but not disappeared, centering of the caliper will be required. To do this, remove the wheel from the bike and align the shoe overhang.
- The same centering eliminates the problem of pads rubbing against the disc. True, the fatigue stress of the frame also plays a role here. the geometry is violated and the caliper is separated from the brake disc. Loosen the caliper fasteners, center the caliper while riding the bike and then tighten the bolts.
- Piston sticking due to dirt can be resolved by a complete bulkhead and lubrication of the assembly.
Braking problems can also be caused by changes in the rotor geometry. Due to imperceptible distortions, the pads will touch the rotor even at permissible distances. Self-repair does not always give the desired results. If it is not possible to achieve the correct operation of the unit, find out how much the adjustment service costs in the workshop, and go ahead.
Why put a support on a bicycle and how to set it up
A high-speed bicycle is a complex and delicate mechanism, almost like a car. Unlike his single speed older brother, he has a developed drivetrain. This allows you to rationally use a lot and expend energy in a straight track, uphill and headwind.
But the other side of the coin, which has to pay for comfortable riding conditions, is breakdowns and frequent maintenance. Transmission problems most commonly include cassette sprockets, chain, tensioner and caliper. Let’s talk about him.
Why do calipers get upset
The reason for the deterioration of the performance of parts is most often wear. It is caused by misuse of the transmission, shock, dirt and irregular maintenance. Indirectly, the breakage of the calipers is caused by a superficial setting.
Inspection and maintenance:
- cleaning and lubricating the chain;
- pulling up the cables;
- adjustment of the front and rear derailleurs;
- compliance with the rules of gear shifting.
With the brake caliper, everything is about the same: due to the ingress of dirt, the pad adheres to the rotor worse. Also, the mobility of the node may deteriorate. changing the allowable distances. which will have to be adjusted.
Typical Mountain Bike Disc Brake Situations:
- friction of the disc on the brake pads due to improper protrusion of the pads;
- a weakened spring (the pads do not bounce back tightly or at all);
- rubbing disc pads at full wheel revolution. caliper bolts not tightened correctly.
It is not necessary to exploit a frustrated or worn out component of the transmission or brake system. this is fraught with unpleasant consequences. The best protection against them is to pay attention to even minor problems and fix them in a timely manner using simple recommendations in the article.
The essence of the basic setup is to set the boundary positions of the switch. In this case, it is advisable to remove the chain. this will be more convenient. Standing behind the bike, we perform the following operations:
- Using the adjustment screw for the limitation of the highest gear (H), achieve the location of the cassette rollers and the smallest cassette sprocket in one plane. There is one secret. if the device is not new and has backlash, the rollers are not aligned with the extreme star of the cassette, but literally by a hair’s breadth from the hub.
- Overcoming the spring force, move the derailer by hand to the extreme left position (closer to the bushing) and, turning the screw L, ensure the alignment of the plane of the rollers with the line of the largest sprocket. Again, if there was a difficult transfer to the rear sprocket with the most teeth, the switch should be shifted a few microns closer to the spokes.
- Put on the chain.
Debugging shock absorbers
On mountain bikes, a shock-absorbed front fork is most often installed, although other types of bikes do not always have one. This is primarily due to the specifics of mountain biking. Shock absorbers differ in the type of work items that are used in them. There are several types of forks:
Spring-loaded ones are the simplest, cheapest and most unreliable ones. Their work is based on spring compression.
Elastomeric, based on a rubber or polymer rod. Although they are more expensive than the previous ones, the quality of their work can hardly be called satisfactory. Therefore, elastomeric shock absorbers are only used in the lower price range forks.
Motorcycle Gearing Changes Explained | MC Garage
Spring Elastomer Shock Absorber
Air. Compressed gas acts as a spring in them. most often air, which is compressed by a piston. They are not suitable for extreme riding and quickly deteriorate.
Oil-air and oil-spring shock absorbers are the most reliable, but also the most expensive.
The design of the air, oil-air and oil-spring forks allows you to adjust the operating parameters, so each rider can adjust them for himself. The suspension forks have the following settings:
- The minimum load or spring rate that is set based on the rider’s weight. Also known as Preload, it is a basic setting designed to handle all the bumps in the road.
- The next important setting is bounce or Rebound. It adjusts the fork release speed. When changing the nature of the terrain along which your path lies, this characteristic plays a crucial role. When driving on uneven surfaces with many obstacles, it should be unscrewed so that the fork can better absorb them. On flat roads, the rebound should be set to a minimum, otherwise extra energy will be wasted when pedaling.
- Compression controls how much oil is passed by the damper in a specific part of the fork travel. There are high and low speed. It is found in products of the highest price range and is used for fine tuning. Thanks to this setting, the compression speed changes non-linearly, which allows you to handle even the smallest bumps or make the fork stiffer for easier pedaling.
- LockOut makes it possible to completely block the fork. Most often used when driving on smooth, flat roads, as well as when climbing a mountain.
Spring oil fork
We have named only the main options for adjusting the shock absorber of a bicycle, but in fact there may be more. It should also be remembered that manufacturers tend to name certain adjustments differently, so before you start debugging your plug, you should carefully study the user manual.
This article describes only the main points that you should pay attention to when self-adjusting your two-wheeled horse. Not all issues were covered in full, since this topic is quite extensive.
We still hope that after reading it, your fear of modern bicycles has disappeared, and you will no longer run to the workshop at the slightest problem. Always remember that it is not the gods who burn the pots. A little patience and success is guaranteed.
Low gear limiter adjustment (L)
The procedure is performed in the following sequence:
- the chain is installed on the largest sprocket in the front and the smallest in the back;
- the cable is disconnected from the dereiler;
- by rotating the screw L, it is necessary to ensure that the chain, when rotating the pedals, moves as close as possible to the inner frame, but does not touch it;
- the cable is stretched and fixed.
How to adjust your bike’s gear shifting
Usually, setting up a Shimano rear derailleur for normal operation is limited to a quick readjustment. To complete it, you need to hang out the rear wheel, which will require one of the following:
- Repair rack.
- Rear wheel stand.
- Ironing board.
- Friend’s help.
Rear derailleur adjustment technology exemplified by Shimano Tourney
High gear limiter adjustment (H)
- the chain is installed on the largest sprocket in the front and the smallest in the back;
- turn the screw H to find the optimal position in which the chain will be as close as possible to the outer frame of the switch, without touching it.
We transfer the chain to the smallest sprocket in the back and to the largest in the front. By turning the screw 2, we achieve the minimum distance between the chain and the frame, but without contact.