mitrofan. Saturday 9 February 2013.
how to make a homemade bike brake
Well, if your bike will be equipped with moped wheels with drum brakes, they can also be driven using standard motorcycle handles. It should be noted that their ends must be equipped with plastic or rubber balls.
A freewheel for a cross-country bike does not need a much more efficient direct drive. The foot brake will be superfluous, and the athlete sometimes has to brake almost simultaneously with the operation of the pedals, and it is also difficult to get under way on the uphills on a car with a foot brake. For a cross bike, it is better to use a hand-operated shoe brakes like those used on sports cars.
The chain drive is different from the standard one. First of all, it has a different gear ratio, as a rule, it is equal to 1. To ensure it, it is necessary to replace the drive sprocket with another one, with the same number of teeth as the driven one.
You can use wheels and from a moped, they are much stronger and have better cross-country ability compared to bicycle wheels, although they are heavier.
The wheels of the cross bike are standard, from “Kama”. It is advisable to choose tires for them with a sufficiently deep tread pattern.
Still, a bicycle fork is far from the best option for a cross-country bike. And if there is a possibility, it is still better to replace it with the corresponding unit from a light moped, for example, “Riga-11” or “Riga-13”.
Extension of the axle of the wheel relative to the fork about 45 mm.
one of our drawings. If your bike does not have a stem, brackets made of 4mm steel sheet are welded to the fork stays to improve handling.
The bike fork also needs to be modified as shown in
It also makes sense to get rid of the hinge at the junction of the steering wheel with the steering shaft. To do this, you need to determine the optimal position of the steering wheel and fix the hinge joint by welding.
The handlebars of the bike should also be reinforced: like cross-country motorcycles, it should have a horizontal bridge. In principle, it is best to use a motorcycle or moped handlebar, reinforced with a pipe with an outer diameter of about 18 mm.
To do this, the flanges of the hinge are first tacked to each other by welding from above and below, then excess metal is cut off with a hacksaw, after which the joint is carefully welded. The welded joint is carefully cleaned so that it does not have sharp edges that could hurt.
Strengthening the frame is also helped by getting rid of the hinge around which the bike was folded.
And there will be a lot of such work when rebuilding a bicycle. In particular, the single-tube center frame is reinforced and is transformed with the help of an additional crossbeam of the tube into a classic triangular frame, which has much greater strength and rigidity. The diameter of this additional pipe is about 30 mm, the wall thickness is 2.5 mm.
The increased durability and reliability are what should differentiate the trial car from the production folding bike. And first of all, all this will be determined by the quality of welding work, which must be performed by a highly qualified welder.
the basic principles of converting serial bicycles such as “Kama” or “Desna” into a car for a trial, based on the recommendations of the magazine “Praktik” (GDR).
In our today’s publication, we want to acquaint readers with
DIY TRIAL BIKE
How to make a homemade trial bike. Details
How to assemble a handbrake on a kid’s bike
A modern road bike with 28 “wheels requires front caliper brakes with an 80 mm distance from the bore to the pads. Here are two proven caliper brakes with a distance of up to 90mm. Both brakes showed full suitability and good quality for me.
Option 1. Caliper brake on one axle (like the Salyut bike):
My weight is 85, from my cruising speed of 17 km / h with emergency braking with one front brake on horizontal asphalt it brakes quite effectively, braking distance of three meters to a full stop.
No special bends or pincers were noticed during braking (thick enough aluminum)
Out of the box, the pliers were not always retracted into the opposite position symmetrically, the right one sometimes remained with the rim touching. I blew the hinge with aerosol graphite grease, squeezed it. Now it seems normal. I had to slightly lower the front wing (within the limits of the norm), the right “tick” touched the wing when I pressed the brake and moved it.
For a walker, it was a perfectly fit brake. The only drawback is that the “tick” levers move slightly up and down in the wing area during operation and the maximum wing raised interferes with the brake operation. Not a problem for standard tires, but when installing 28×2.00 tires it is better to raise the fender as high as possible.
Subsequently, I rearranged this brake with one axle on my daughter’s bike (wheels 16 ″), it was installed perfectly.
Option 2. Caliper brake on two axles (similar to the HVZ bike):
With a uniaxial brake, the pincers moved slightly down to the wing during operation, and the wing had to be lowered slightly. With biaxial pliers, all moving parts on the wing side move only to the sides, so the wing can be raised as much as possible. This is important for me, because I have 28×2.00 tires instead of stock 28×1.75. there is not enough space.
The new two-axle brakes have short pads, it seems that at minimum speeds they work harder than the previous single-axle brakes, and, on the contrary, they brake less intensively at high speeds. But most likely the whole thing is in the pads, on the new ones they are not only shorter, but also to the touch a little more “plastic”.
The biaxial ones have a simple clamp synchronization mechanism, which is good. The axle of attachment to the fork on biaxials is several mm longer, this is also good. In terms of quality, both the old single-axle and the new two-axle are comparable. service brakes, work normally even on small hills.
(in the photo, the pincers axles are smeared with graphite grease to protect against dust)
Unpacking and Installing Basic Bicycle Parts
This is what the bike box looks like when it comes from the factory. All bikes usually have a crankset, chain, rear and front derailleur, rear wheel, brakes and steering column already installed.
Separately packed steering wheel, seat, front wheel, pedals, reflectors and other small things.
A number of tools are required to assemble the setup:
- hexagons (4, 5, 6 mm), or better a set,
- wrench 15 (for tightening the pedals),
- key for 10,
- Phillips screwdriver,
- pliers (for crimping the cable),
- wire cutters (for cutting the cable).
We take the bike out of the box. With nippers or powerful scissors, we cut off all plastic clamps and remove the packaging. Be careful. it is easy to damage the paintwork of the frame at this stage.
The bike is ready for assembly.
First, attach the saddle to the seatpost. To do this, use a 6mm hexagon to unscrew the mount on the seatpost, install it in the grooves of the saddle frame, close it with a bracket on top and tighten it. This clever design also allows for back-and-forth movement and tilt adjustment. Now it is enough to just tighten the bolt, and it will be more convenient to make settings on the assembled bike.
We fix the reflector as close as possible to the saddle.
We lower the entire structure into the seat tube to the end and secure it with an eccentric clamp. If it closes too easily, then open it to the end, turn the tightening wheel and try to close it again. If it does not close, on the contrary, weaken.
Next, we are engaged in the removal of the steering wheel and the steering wheel. On different bicycles it is different: either the stem is already attached to the handlebars, or not. In any case, the stem is set first. When installing the stem and handlebars, pay attention to the derailleur and brake cables. they should not be tangled. Pay attention to the vertical marks on the stem. this is the maximum possible lift.
There is an important bolt hidden under this little plug! Using a 5 or 6 hexagon, the stem is fixed in the steering column, and the steering wheel is height adjustable.
Let’s take care of the front wheel. First you need to correctly install the eccentric (it is in a box with small things). The photo shows the correct position of all elements. Pay attention to the springs. they are located with a narrow part inward, i.e. to the wheel.
Remove the plug and spring from one side of the eccentric (from the one where there is no lever) and insert the axle into the front wheel hub. The question may arise, which side to insert it? Just look at which side it is mounted on the rear wheel (usually on the left) and follow the analogy.
Next, insert the wheel into the fork. It is necessary to “unfasten” the front brake of the bicycle in advance (in the case of rim brakes) or remove the rubber band from it (usually in the original packaging it is fixed with an elastic band or a tie).
The easiest way to tighten the eccentric is to approach the front of the bike. In this case, you can track whether the wheel is centered. Tightening is done as follows: turn the wheel clockwise to the left and try to close the lever. If it closes very easily, fold it back and turn the wheel again until the eccentric closes with force. You don’t need to overdo it, otherwise you can break the eccentric!
Now you can pump up the wheels. Recommended pressures are always printed on tires in psi and bar. Bar = atmosphere. Please note: the pressure in the bicycle wheels must be 3 atmospheres and higher. 3.5 is the best option. 2.2 like cars is no good. During operation, periodically check the pressure in the wheels. this is a guarantee of the absence of “eights”.
Install the pedals. The photo shows that each pedal is labeled as L or R. Sometimes stickers are also molded. L (Left). left, R (Right). right. Be careful: the pedals have different threads! Both pedals are twisted “in motion” of the bike, i.e. left to left (counterclockwise) and right to right (clockwise).
First, we twist them with our hands, and then we tighten them with a key by 15.
If the chain is not in place, it can easily be returned there. To do this, press on the rear derailleur foot and the chain looses. Now you can simply grab it with your hand and put it on one of the chainrings.
Installation and adjustment of the front brake; adjustment of both brakes
Now let’s start installing the front brake. Find a curved tube like this in the box. You need to thread the front brake cable into it so that the wide part is at the top, and the narrow tip at the bottom is closer to the brake levers (on the next photo).
We do it as in the photo. The elastic must be put on before you fasten the cable. An elastic band is needed to protect the cable from dirt.
Now we loosen the bolt and put the cable there.
We squeeze the levers so that 2-3 mm remain from the pads to the rim. and tighten the bolt (without fanaticism, otherwise the cable will start “pushing”).
We leave a small part of the cable (5-7 cm.), Cut the rest with nippers (nippers are needed very good, otherwise the cable will fluff at the end). Next, put on the tip and clamp it with pliers. If you don’t have the right tools at hand, take this step later. But do not postpone for long. the cable may “fluff” and you will have to change it.
Further, the cable can be wound by the lever so that it does not dangle.
Now you need to adjust the brakes. It would be good to devote a separate article to such a difficult question, but now I will try to briefly describe the adjustment process.
The precise operation of the brakes consists of many nuances. First, spin the wheel (having previously inflated to the recommended pressure). is there an eight? If so, then it needs to be fixed. It is better to do this for an experienced craftsman or look for an article on eliminating eights on the Internet. If everything is in order, we work further.
When assembled, the brake pads must be at equal distances from the rim. This is achieved by tensioning the cable. you can loosen the bolt with which you attached the cable and tighten it more. And then there is the “lamb”. it is right next to the brake lever. they can also tighten or loosen the cable. Never screw it out completely! The pads themselves must be parallel to the rim. Check if this is so. If not, you need to loosen the bolt that secures them and adjust their position (see photo). You can, for example, clamp the brake (then the pads will press parallel to the rim) and immediately tighten the bolts.
Now we press the brake lever and see how the brake levers come together. And they must converge at the same time! Look at the video.
If, when you press the brake lever, one lever presses the shoe faster than the other, you need to make the adjustment with special screws (see photo). The adjustment is made as follows: choose the lever where the shoe is faster and stronger pressed against the rim and the screw on this side tighten clockwise by one or half a turn. Click and see if the situation changes. Usually, the pads begin to press against the rim at the same time after adjustment with one screw. If not, then turn the screw on the other lever (where the block is farther from the rim) turn counterclockwise by one. half a turn. Continue the described steps until you achieve the result, as in the video. The same procedure must be done with the rear brake.
Checking the condition of the brakes
First of all, we “unfasten” the brake, as shown in the photo.
Check how the cable (G) moves in the shirt (A) by pressing and releasing the brake lever and pulling the cable back with your finger. the movement should be free, without delay. If the cable pulls hard, it may be damaged, the shirt or cable guide (C), or dirt has accumulated inside the jacket or cable guide. They must be removed and cleaned or replaced.
Check the condition of the pads (J). Grooves for the drain of dirt should be visible on them (the block should not be smooth). Worn pads without grooves must be replaced. Check that the pads are complete with washers and that they are correctly installed.
Observe the order of washers when installing new pads.
The brake levers (I) must rotate freely in their seats and spring apart after compression. If the movement is difficult, the brake during operation may get stuck in the closed position and rub the pad on the rim. In this case, you can remove the levers from the seats, clean and lubricate the contact points and reinstall.
When installing, make sure that the protruding pin on the arm fits into the hole in the frame, and that the hole on the left and right arm is the same.
Adjust the position of the pads
“Fasten” the brake by squeezing the levers and placing the cable guide (C) in the stop (D). Loosen the shoe fixing bolt (K) with a hexagon. We press the lever with the block to the rim and set the block so that it:
- adhered to the rim with the entire surface
- did not touch the tire
- parallel to the rim
In this position, the block must be fixed by tightening the bolt. When tightening the bolt, the shoe may move and must be corrected. It will be easier if you find an assistant who will grip and hold the brake lever while you tighten the bolt.
If your brakes squeal, try the following.
Before tightening the bolt, place a folded sheet of paper under the rear (in the direction of travel) of the shoe, then tighten the bolt. So the pads will be smoother to press against the rim during braking (first by the front, then by the rear) and will not “creak”.
We do similar operations with the second block.
We set the levers symmetrically
For the left and right shoes to wear evenly, they must be at the same distance from the rim. Adjustable by spring tension on the brake levers. To equalize the force that returns the left and right brake levers to their original position, use the adjusting bolts located at the base of the levers.
By twisting the bolt clockwise, we tighten the spring, unscrewing it. weaken it. By pressing and releasing the brake, we check the uniformity of the removal of the pads from the rim. Tighten the bolts on the left and right sides until the pads move the same distance when the brake lever is released.
Adjusting the position of the brake lever and the tension of the cable
To bring the brake lever closer to the steering wheel (for example, so that you don’t have to stretch your fingers too much), tighten the bolt on the brake lever.
In this case, keep in mind that you should not bring the handle too close to the steering wheel. It should not touch the grip when fully clamped.
When the position of the brake lever is set, it remains to adjust the cable tension. The task is to bring the pads as close to the rim as possible, leaving a distance of 2-3 millimeters between the pad and the rim.
To do this, you can tighten the cable in two ways:
- For a rough adjustment, if the cable is very weakly tensioned, and the pads are far from the rim: loosen the bolt fixing the cable in the brake lever, tighten the cable, tighten the bolt.
While loosening the bolt, hold the lever and cable so that the cable does not “run away” and do not have to re-thread it into the seat.
for fine tuning, we use the adjusting screw at the point where the shirt comes out with a cable from the brake lever.
To make the screw spin freely, loosen the lock nut by unscrewing it counterclockwise. Turning the screw clockwise, we release the cable tension (the pads move away from the rim), unscrewing it counterclockwise, we increase the tension (the pads are closer to the rim). When the pads are in the desired position, tighten the lock nut.
That’s all! Checking how everything works. If necessary, re-adjust the springs of the levers (item 3).
Braking tuning requires attention to every detail, from the brake levers to the brake pads.
First step. Adjusting the brake levers
Brake levers should be located so that they can be reached quickly and comfortably. In order to adjust the position of the brake lever, loosen the fastening screw, place the handle as it is convenient for you and fix it. Usually there is a screw on the brake lever, with which you can adjust the distance of the brake lever to the grip. adjust the position of the lever with it.
Step two. Position of the brake pads
It is easier to adjust the position of the brake pads as follows: press one of the pads with your hands close to the rim, adjust its position. Make sure that the block is not too low (the edge of the block is below the rim), but not too high. the block touches the tire.
I would like to draw special attention to the next moment, since there is little clear written about it. Until the nut of which the shoe is fixed is not tightened, the shoe has three degrees of freedom: the washers form something like a ball joint. (Pay attention to how many washers are there? That’s what they are for!). It is believed that the leading edge of the pads should touch the rim slightly earlier than the rear. Therefore, we do this: we put a small gasket under the rear end (see fig.).
This number of washers is needed to get something like a ball joint
Now you can tighten the nut that fixes the shoe.
Step three. Centering the positions of the levers
At this step, you need to fix the brake cable: so that the brake pads touch the rims at least a little if you press the brake lever. At the bottom of the levers there are special bolts that adjust the tension of the springs that press the pads against the rim.
We set it up as follows: press the brake and see which of the pads touches earlier. For the one that touched earlier, we increase the spring tension (or vice versa, weaken it on the other side). It is necessary to ensure that the pads touch the rim at the same time.
Fourth step. Adjusting the distance from the pads to the rim
I believe that this distance should be as small as possible. (1-2 mm. If the rim is even). But then the brakes will work very sharply. the slightest pressure leads to sharp braking. Therefore, the distance can be made a little more.
The distance is adjusted in two steps: first, due to the screw with which the cable is attached to the brakes. Then fine tuning on the brake lever.
The large washer acts as a lock: when it is tightened, the cable tension adjustment screw cannot be turned.
How to slow down on Fixed Gear?
For many, the bicycle has long become an alternative to both a personal car and public transport. and more models of this two-wheeled iron horse, created purely for sports purposes, can be seen on city streets. Fixed weights, originally created for track racing, are no exception.
What is Fixed Gear?
The main difference between these bicycles and other models is the absence of the usual hand brake. Many people do not understand how to brake on a fixed bike, because its pedals rotate both forward and backward. It will not work to slow down on the fix (it is rather difficult) with the help of the pedals, because the model is specially designed in such a way that they rotate constantly.
The fact is that for the bike to move, they need to be constantly twisted. they rotate with the movement of the wheel. Nevertheless, Fixed Gear is gaining more and more fans thanks to its interesting minimalist design and ease of maintenance.
Before getting into the saddle of such a bike, you need to figure out how to brake on a fixed bike in theory. Or for a start, put at least the front handbrake. Learn more about Fixed Gear.
Braking Methods on Fixed Gear
For beginners and advanced cyclists, there are their own methods of braking with fixed weights.
Asking the experts on Fixed Gear how to brake on such a bike, you often hear that you can stop abruptly with your feet. But for beginners, such a trick will not work, because with a lack of skills there is a danger of being seriously injured.
Experienced cyclists who are mastering this model can use a method called Skid Stopping (skidding or skid braking). This is a favorite of many fans of extreme cycling fixse skid braking. When performing such braking, it is necessary to rise strongly and shift the center of gravity to the front wheel (be above the steering wheel). At the same time, the legs resist the movement of the pedals as much as possible. Toe-clips with straps are best for this, which reliably fix the feet on the pedals. At the same time, the rear of the fix bike often skids when skidding. With the help of such simple actions, you can both brake and perform various spectacular stunts on Fixed Gear. For beginners, Pace Pedaling is the best way to brake on a fixed bike. To perform it, you must prevent the rotation of the pedals. At the same time, the speed of the bike starts to decrease. It should be noted that the fix is not capable of stopping abruptly, therefore it is necessary to have an excellent eye and correctly calculate the stopping distance.
Fixed skidding: theory and practice are inseparable!
Having studied all the methods of braking with fixed weights in theory, it will not be superfluous to practice a little. To do this, it is worth choosing a place with the most even road surface. A schoolyard or a spacious parking lot is suitable as a training ground. It’s better to hone your skidding skills on a fix gradually.
Professionals are sure: once having chosen such a bike, in the future you will hardly be able to refuse it, because a fix is the model that modern fans of extreme, adrenaline and gambling bicycle racing along city streets choose.
Forgotten for a long time, the game of bike polo is back in fashion. This team sport attracts owners of various bikes, including city bikes and fixed bikes, as it does not require special technical equipment. First appearing in the 19th century, the Urban Bike Polo.
Are you tired of the bike “like everyone else”? Looking for something different but easy to use? Buy a fixed gear bike. What is a fixed gear bike? Experienced cyclists sometimes call it for short. fixie (fixie). But in.
Fixed gear, that is, single speed bicycles without freewheel. today are very popular all over the world. Thanks to the high degree of control over the bike, a wide variety of complex tricks can be performed on it. Sur place Surplus or track stand (from.