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Why Do Mountain Bike Disc Brakes Lock Up Instantly?-Here’s why

It mostly happens on cornering trails, when you turn the handlebar of your bike, brake cables are not enough long to stretch and release with a turning of handlebars, and these cables would be stuck and cause stretch which would lock the disc brakes thoroughly and when you handlebar returns to its original shape and condition in a normal state, then the disc brakes will unlock, it happens when you have turned the handlebar in the opposite direction of the cables routings installed in your bike.

If you have not inspected the inner routing of your brake cables, then it might be possible that your brake cables would stuck, it only happens when your bike has internal brake routings, or if you have installed external brake routings, then check the internal fluid and oil and also the cables, brakes need servicing in every month, stucked brakes would lose working when you pull the levers of the brakes even if the calipers and rotors of your brakes are new and smooth working, it will also hang the calipers and rotors due to which disc brakes would cause locking.

If the brake levers are not working normally when you pull them, these would stop near the grips of the bars and do not come back to their original position, then it is also a major problem for causing locking of the disc brakes, the reason is that even one to second of stopping and jamming of the levers of brakes would lock the disc brakes, levers need proper servicing and cleaning to clear all the debris and dry oil which is affecting all the brake system of front and rear disc wheels.

When disc brakes become old after riding too much on the terrains, then the inner ramps of the calipers would ruin and these would not function properly when you pull the levers of the brakes, these ramps would play a major role in capturing the outer edges of the rotors and stopping of bike wheels, it only happens when you have used disc brake for many years, these are the signs to change and replace the calipers of the brakes.

Damaged Brake Pads:

Brake pads also have a limited life range and these are the main brake parts that are 80% involved in stopping bike wheels with power and these are connected with the rotors, too long usage would ruin their ability and power of stopping bike wheels on a normal basis, it only happens because these pads would rub so badly that these will lose their functions and also these would cause bending and deforming due to which these are not able to stop the rotating rotors of the wheel with power and force, these would start creating bad and irritating noises from the braking areas of the wheels, you have to replace or upgrade your brake pads to get rid of this problem.

Sudden Pushing Of Brake Levers:

In cases when you are going on downhill trails at higher speeds on cornering and twisted terrains, then on every corner near trees and mountain walls, you have to apply force on the levers with a sudden push and with a large force, in those cases if your brakes are older and cheap, then your it will cause locking of your wheelsets, the rotor does not unlock easily after few seconds it will come in its normal working position.

Using Fingers For Pushing Of Disc Brake Levers:

Disc brakes have much more braking power as compared to old traditional rim brakes, for rim brakes, we used all of our five fingers and palm hand to push the levers of the rim brakes, but for disc brakes never use five fingers for pushing levers, disc brake levers need just a push of one to two fingers and the wheel will stop abruptly due to more advanced features of disc brakes. using more than one to two fingers for disc brake levers causes locking of the disc brakes.

It is a serious issue because it needs improving your skills for braking of both front and rear wheels and you have to learn at the beginning about using a lesser number of fingers, although it is hard in the beginning over time you would easily adapt and remember fingers for braking.

Heating Of The Internal Brake Fluids And Rotors:

If you are a mountain biker and you love long mileages terrains for both roads and mountain biking, then it is a must to install better quality and expensive brands of disc brakes because cheap and old disc brake fluids will heat up after riding half an hour regularly on the terrains when the internal fluid and rotors got heat up then these will lose their ability of braking and the rotors would not respond with the calipers of the disc brakes.

In summer seasons, the internal fluid of disc brake got heats up due to which this fluid would start expanding and their volume increases within the cables from the actual recommended volume, these expansions of fluids would block and lock the brakes and affects badly the normal and smooth working of the disc brakes.

Which Brands Of Disc brakes Do Not Cause Locking Of Disc brakes?

If you are looking for better and long-lasting disc brakes to get rid of locking problems, then Magura and Avid companies of disc brakes do not cause locking while Shimano and Hayes disc brake companies are older and have many complaints regarding locking of the disc brakes. a common reason is that brakes and rotors of these Magura and avid companies would not heap up on the terrains and cold internal brake fluids and cold rotors would work normally and smoothly with better braking power ability.

Swapping The Levers of Front And Rear Brakes:

Disc brakes have long cables in length and do not need cutting in those conditions when you want to swap the levers of front and rear brakes, then it would be a better and worthy step, you can install the front brake lever on the left side while rear brake lever on the right side of the handlebar grips, it is an experienced and experimental step to avoid locking of the disc brakes, although it would cause a little bit of difficulty in handling and gripping of the bike on aggressive terrains, but as time passes you will easily learn and handle your bike with this setup.

What Is The Main Purpose Of Locking Disc Brakes?

Almost all disk brake have a locking system, if you start thinking deeper then it is also in favor of a rider but if you are a beginner then you need to learn thoroughly about locking skills, locking of disc brakes prevent sliding and skidding of the rear tires and minimize the speed and the trails on which you are riding at higher speeds with better traction, locking of the rear wheel would break the traction of the bike with the trail, there are also other many advantages of locking of disc brakes, a beginner rider needs to learn and it takes almost many months to train fully and level up for locking of disc brakes.

Disc Brakes Containing Dot Fluids:

All the brands and companies of disc brakes do not contain dot fluids within the cables, but there are few brands of disc brakes which contain internal dort fluids within the cables of disc brakes, there is a major disadvantage of these dot fluids, these are hydroscopic and these can easily mix with the water and make a mixture, the same problem starts within the brake cables and the water starts making its place within the cables, now water needs to evaporate and it starts sweeping down towards the calipers of the disc brakes, when the liquid reaches the calipers between the brake pads, these would decrease their functioning, there is a large difference between the densities of water and dot fluids, as a result, locking of disc brakes takes place. when looking and purchasing new disc brakes never buy dot fluid disc brakes, Shimano brakes do not contain dot fluids in their cables.

Lever Bolts And Brake cable:

Screwing bolts of the levers need to be adjusted with a medium force, if these are tight enough then the locking problem is arising from these levers, you have to maintain and adjust the levers by noticing the calipers, if these are moving rapidly back and forth by pushing off the levers and holding the edges of the rotors on every lever push, then the levers are normal, after that check the cable, if it’s junky and it is creating much more friction so that it is not moving back and forth normally same as that of the new cables, then you have to replace cable of your disc brake.

The best method of checking the quality and working performance of cables is that, push the levers of the brakes almost 5 to 10 times continuously and then leave, this pushing and leaving of the levers would remove all the moisture and air which is present within the cables with the internal fluids, this process will remove all the internal air out from the brake cables and disc brakes would become normal and smooth.