DIY bicycle fork repair

Regular service and timely bicycle fork repair - an important point in the maintenance of equipment, which helps to prevent the failure of the entire structure.

A fork is a part of the steering mechanism that is connected to the front wheel, steering wheel and frame and has a number of key functions:

• keeps the front wheel upright;
• makes it possible to control the direction of movement of the wheel, adjusts the angle of its rotation and maintains the trajectory of rotation;
• when using the front brake, it takes over the resulting loads;
• acts as a shock absorber, smoothing vibrations and vibrations from road irregularities.

Different bike forks differ in:

• the diameter of the wheel they can support;
• type of fastening of the front brakes;
• the presence or absence of shock-absorbing capabilities. They are rigid (hard) and shock-absorbing (soft). The former are usually mounted on road or specialty bikes designed for riding on flat, hard surfaces. But the vast majority of models are still equipped with soft forks, as they increase ride comfort and improve control at high speeds;
• the travel of the suspension forks. The smoother the surfaces on which the bike is operated, the less fork travel is needed - and vice versa.

Rigid forks are generally inexpensive, require minimal maintenance, and are structurally simple and reliable. Soft ones are often more expensive, high-tech, require regular maintenance and more often require repair of a bicycle fork.

Video (click to play).

The periodic need to repair a bicycle fork with shock-absorbing elements is due to the complexity of its design, where each element carries a certain load and may fail.

Simplified, any fork, including the hard one, consists of:

• steering tube (rod) - the axis connecting it to the frame and the rudder stem;
• the stem is securely pressed into the crown, from which two "legs" further extend;
• legs (in the case of a rigid fork - a feather) - two vertical tubular profiles;
• dropouts - the axle of the wheels is attached to them.

If we talk about soft forks, then in their legs there are shock absorption elements: springs, a damper, external adjustments. Unlike a rigid fork, the "legs" of the shock-absorbing fork are inserted into special casings - "pants" like a piston, which end with a dropout.

Like rear shock absorbers, soft forks can be of different types: spring, elastomeric, oil, air, or combined, for example, air-oil, oil-spring or spring-elastomeric - depending on which substance acts as a damper.

To ensure the front shock absorber has a longer life and to avoid too much bicycle fork repair, it is necessary to periodically clean and lubricate its moving elements (legs, oil seals), and in the oil version, change the oil at least once a season.

Correct use and adjustment of suspension fork settings to reduce the likelihood of bike fork breakage and repair

In addition to servicing and repairing a bicycle forks with shock-absorbing elements, some models of two-wheeled vehicles make it possible to change and customize certain parameters for themselves:

• the fork lock completely locks the fork mechanism. It can be useful during a power ride uphill or during acceleration - it prevents the absorber from absorbing energy and swinging when pedaling, increases the efficiency of muscular efforts;
• preload makes it possible to set the minimum load at which the shock absorber starts to work - that is, the user can independently set the spring rate. With the correct setting, it optimally dampens vibrations from pits and shocks, while maintaining firmness on a flat surface;
• Compression is the adjustment of the compression speed of the fork. Reduces swing during pedaling and allows you to quickly "catch" irregularities, providing a more stable and even stroke;
• shock absorber rebound - the speed at which the fork is released and returned to its original position. The rebound speed should be such that the shock absorber can extinguish the energy of the next obstacle before it goes to the steering wheel.

Correct adjustment of the front suspension settings determines the efficiency and comfort of movement - it must fully correspond in all parameters to specific riding conditions. An illiterate setting will not only reduce the dynamic capabilities of the technique, but can also lead to the need to repair the bicycle fork.

Our workshop offers sportsmen and cycling enthusiasts the repair of bicycle forks of any type and complexity.

A suspension fork is one of the key components of a bicycle, and its parameters and settings must clearly correspond to the purpose of a particular model and riding style.

We offer the services of professional craftsmen who will quickly and efficiently perform the entire range of necessary work from installing a new unit and adjusting its settings to maintenance, as well as partial or complete bicycle fork repair.

If you do not know how to remove and disassemble a mountain bike suspension fork for maintenance, repair or replacement, then this article will help you find out what you need for this, and how to do it at home. Also, such questions will be considered here: how and how to lubricate the front fork, the frequency of maintenance and other tips on this topic. All this will be presented in the form of detailed instructions with pictures for each action, as well as a video on disassembling a bicycle suspension fork. In this article, we will analyze the RST GILA 100 mm spring-elastomer fork with disc brake mountings.

A bicycle fork, like all other components, can be replaced, repaired or serviced. Therefore, before proceeding with these procedures, we need to remove it from the bike, and in some cases disassemble the shock absorber for parts. In what cases will we have to remove it? First of all, this is when it is replaced by another. Secondly, it may be necessary to replace bearings and / or support cups, apply new lubricant, and also, there are times when it is necessary to align the steering tube or perform other repair work.

Disassembling a fork shock absorber is most often necessary to replace lubricant or worn components. For example, these can be oil seals (cuffs), etc.

Below you will find detailed instructions for dismantling the front suspension fork with explanatory pictures.

1. First of all, we carry out preparatory work, namely, we unscrew everything that is attached to the plug. In our case, this is the brake caliper, as well as the front disc brake hose, which is clamped to the fork legs. If you have V-brakes installed, then dismantle them. This also applies to the speed sensor from the bike computer, front fender, etc.
2. Unscrew the bolts securing the stem to the steering tube, and then unscrew the bicycle fork anchor bolt.
3. Carefully remove the steering wheel together with the stem and lower it down. At this stage, you should act carefully so as not to damage the hydraulic lines or accidentally hitting the metal parts of the steering wheel on the frame, so as not to scratch the latter.
4. Remove the spacer rings and the guide sleeve (cone).To do this, carefully pry it with a small flat screwdriver in the area of ​​the cut. Then we take out the upper rolling ring and the upper bearing. All these actions are illustrated by the pictures below.
5. All operations have been completed and now you can carefully remove the steering tube from the glass. After that, it remains for us to get the bearing, the lower rolling ring and remove the front wheel. To do this, we loosen the eccentric or unscrew the fixing bolts (depending on the type of attachment). This completes the process of removing the bike fork.

After we have removed the suspension fork from the bike, old used grease should be removed from all of the above components, namely the bearings, cups and raceways, as well as the steering tube and other areas. It's not worth applying a new one yet, we will add it back to the glass at the stage of installing the fork.

Next, let's start disassembling the shock absorber for further lubrication replacement.

1. Turn the plug over and unscrew the mounting bolts.
2. We remove the pants from the legs of the fork. If necessary, remove the oil seals.
3. We remove used lubricant from all accessible surfaces. This procedure can be left for later and performed after complete disassembly, but it is preferable to do it right away in order to avoid oily marks on clothes, tools, etc. Do not forget to remove dirt and grease from the cuffs of the bicycle fork, as well as from the inside of the pants themselves.
4. Then remove the lower travel stops and stop stops. To do this, we apply a little effort and pull them off the rods.
5. We unscrew the adjustments on each of the fork legs. They are unscrewed using a special key, which, unfortunately, we did not have. Therefore, we had to make our own self-made key for these cases. We will attach a photo below, if it will come in handy to someone. We take out the springs with caps and elastomers, as well as two rods (one from each leg).
6. We remove the old grease from all surfaces of the fork.

This completes the process of disassembling the bicycle fork shock absorber. Next, apply new grease. We will consider what can be used as a lubricant below.

I use Litol-24 grease to lubricate all the components of the bicycle front fork, including both the shock absorber and the head tube bearings. It is believed that it negatively affects aluminum parts when moisture enters. But using it for five seasons, no negative consequences were noticed. The advantages of this grease include good temperature resistance. It does not thicken both in severe frost down to -50 C and in extreme heat (up to 150 C).

Many people advise pouring liquid machine oils, sewing machine oil, and others into their forks. Personally, in my experience, a deterioration in the operation of the fork shock absorber was noticed (jerks were observed during compression and rebound of the spring). And if liquid oils worked better, manufacturers would fill them in initially, which they don't.

We figured out how to lubricate the bicycle fork. Next, let's see how to do this. We apply grease to the spring with excess (we ram the lubricant between the spring rings), the excess will come out through the hole under the stem and, if there is an excess in the pants, it will be squeezed out through the stuffing box seals (but you shouldn't overdo it either). We also apply grease to the grooves of the cuffs and add forks to the pants. We lubricate all rubbing parts with a thin layer.

Before installing the plug into the glass, do not forget to lubricate the bearings, rings and cups.

This completes the lubrication process and you can go back to assembling and installing the bicycle fork.

The process of assembling and installing the bicycle suspension fork is carried out in the reverse order. The only thing that you should carefully and carefully perform this operation in order to avoid incorrect installation of components. After you have installed the assembled fork back on the bike, secured the stem, be sure to check that there is no play in the steering tube in the frame glass.If they are observed, then be sure to eliminate them before the trip.

After you set everything up and start riding, for the first time, there will be an abundant release of lubricant through the cuffs of the bicycle fork pants. Don't worry, this is normal. Over time, excess oil will be squeezed out, and this process will stop. During this period, don't be lazy and remember to wash off excess lubricant after each ride.

The frequency of changing the lubricant of a bicycle fork depends not least on the road surface on which you are riding. If your routes contain an abundance of dust, mud, sand and other abrasive material, then the frequency of service should be increased. Here we give the average figures after which maintenance should be performed.

Approximately every 700-800 km, the oil seals should be disassembled and lubricated, and every 4000-5000 km the entire fork is moved and lubricated.