To most of of us it is disconcerting braking power feels poor often a sign of brake cables to short causing cable drag often due to some modification to the handlebars specially if a custom handlebar arrangement.
Rim and mechanical disk brakes are controlled by a inner wire cable sliding in the outer cable. If they don't t slide back and forth properly causes the inner wire cable dragging.
Do this simple test. Squeeze the handle bar levers feeling the squeeze of the lever observing how the pads compresses the rim. If the pads grip the rotor flush the handle bar lever should should feel solid straight away a good sign of free cable movement. When you let go of the lever the pads should retract away from the rim evenly.
Check the inner wire cable connection in the handle bar lever if the wire is frayed ready to come adrift at any time.
Check the handle bar lever cable adjuster screwed out to far causing stress on the tip of the shred pulling it towards you every time you squeeze the handle bar lever often striping both the adjuster and lever threads becoming sloppy due maximum adjustment. There are also adjusters on the brake calipers.
On the wheel side of the caliper, not the frame mounting bolts, there is two Allen key mounting bolts. These are only to be loosened just enough for adjustment only. Once loose enough by trial and error twist one direction and try the handle bar lever. If worse try the other direction. By this trial and error technique you can get the pads to move on and off from the rotor properly.
When you squeeze the handle bar lever the pads should compress both sides of the rotor flat and true.
Retighten. Watch you don't wrench the bolts. Just a light tug they can't move.
Check the pads squeezing the handle bar lever again.
Braking efficiency will also depend on how much the condition of the rotor is. So on inspection the surface should be like a new one, clean, smooth and shiny like a mirror. Examining the rotors of new bikes what they look like, should look the same an excellent rule of thumb guide.
Looking at the rotor where the light shines on a angle to you will show up a dirty rotor can get. So too the surface of the pads should look equally clean like new ones.
When assembling pads an incorrect assumption dabbing some grease behind them in an attempt to improve freedom of moment, vibration and squealing, the grease will only end up getting onto the pads absorbing it. To keep the pads and rotor clean while handling it is prudent hygiene practices while handling these parts. Pristine clean hands can be achieved cleaned with washing machine soup powder.
Spongy brakes is often deceiving one thinks of warn pads. Pads in good condition not retracting away from the rotor properly is the cause of a spongy feel. They are not necessarily that warn.
This is often caused by handle bar adjustment or modification causing changes in brake cable tension. It is also misaligned pad recesses. In both cases doesn't allow the pads to retract back into the recess housing away from the rotor properly. The steering angle tension will tend to pull on the cables.
The pads are sticking in the recesses preventing them from retracting back away from the rotor properly. If the pads do not retract back into the recesses properly when the handle brake levers are squeezed dragging on the rotor compress the rotor skewed the cause of the spongy feel.
Any modification to the handlebar arrangement will effect the tension of the brake cables effecting the pads to retract flush back into the recess away from the rotor property. In the in instructions shows how you can compensate the difference of the handle bar modification adjusting the brakes after replacing pads.
If brakes are to be replaced are fitted so the recesses are properly aligned allowing the pads freedom of movement to retract back into. As in any brake system the efficiency of the spring can effect braking performance.
A good long hard look at the rotor for any evidence of brake pad dragging ware is prudent. Evidence of brake pad ware is evidence of sticking brake pads. In other words the rotor can help determine if they are and how much possible ware is done. Don't rubyour fingers on the rotor. Be like a CSI investigator that doesn't touch crime scene evidence only look and even then handling with gloves, prongs and tweezers to prevent cross contamination transfer.
Access requires only one all round Allan key except there is no room for a key for the rear wheel brake lever because of the frame. A spanner is required there.
Gather a try, biscuit tin or low cardboard box to catch the parts as they fall to the ground so you don't lose the vital bits.
Wash you hands in clothes washing soup powder so they are pristine clean as a insurance against oily transferee. Turn the bike upside down resting on the seat and handle bars.
In the light eye the rotor running between the caliper. In perspective to the bike up side down moving the caliper brake lever downwards you'll observe the pad on the wheel side will not move while the other side moves onto the disc.
When reassembling pads make a note to resemble them so they compress the rotor flat and retract from the rotor back into the recesses properly the key to the brakes working best.
Remove the wheel.
Put the parts catcher in position to catch the bits when they drop out.
The wheel removed undo the cable from the brake caliper lever anchor bolt. Just undo enough to clear the wire cable leaving the bolt on the lever.
The same Allen key that fits the cable anchor bolt will fit the two bolts on the wheel side of the caliper. Don't be shy to put some weight on them to undo. But don't be rough unscrewing because of the aluminum threads. They must be with drawn out dead straight.
Once the bolts are withdrawn the cover comes off one or both pads along with the spring may fall into your catcher. Remember you are handling the brake pads from now on so your hands should be pristine clean to insure you don't transfer oil and crease to the oil absorbing pads and rotor.
Examining the spring is a “V” shaped spring steel spring clip each tip crumpled with a "u" shape hook that fitted in a slot in each pad. The spring was effectively sandwiched between them.
Looking carefully at the pads based on new ones observing ware will determine how close the spring will be to scrapping the rotor. It is also a good indication the pads were not really retracting back into their recesses properly causing brake drag on the rotor.
An inefficient spring can be fixed by gently bending it wider, remembering to bear in mind to be careful not to distort it that it become useless.
Reassembly is tricky as it is a bit fiddly. Fit a pad color side into the corresponding recesses in the caliper and the spring in the corresponding pad slot.
Correspondingly fit the other pad color inwards the cover recess guiding the cover hooking the tip of the spring into the hook in the slot of that pad.
Line up the cover to the threads. Careless fitting of the two bolts into theses threads here is the major cause
of stripping the caliper threads rendering it useless. Screw the bolts carefully dead straight with only fingers. Never force them with the spanner if they feel a bit tight. Carefully withdraw and jiggle the cover a bit so the bolts can finger screw with out any grinding tight feel freedom of movement.
If the spring is efficiently spreading the brakes, and you have the recesses properly aligned as you tighten the pads will retreat back into the pad caliper recesses neatly flushed. If the don't undo and reset the caliper cover so the pads do.
Check the pad freedom of movement are not stickling by moving the caliper brake lever. If the they stick loosen the bolts jiggling the cover moving the caliper brake lever until they do and tighten. The final tighten of the bolts is another area that will strip the caliper threads. Don't wrench. A light tug they can't and no more.
Keep an eye on the freedom of movement by double checking every step of the way the pads are not sticking so they are flushing back into the Caliper recesses properly.
The next step is the refitting the wheel. With the pads sitting flushed back into their recesses properly the rotor will fit between the caliper just like that finalizing the tightening of the wheel nuts or if a quick release and double check the freedom movement the pads have fully retracted back away from the rotor.
If it appears something is preventing the wheel to fit in place one of the pads or both is preventing the rotor from sliding between the two pads a sign it is catching on a pad because of no freedom of movement to retract back into the caliper recess. Double check they are not sticking by readjusting the housing. When you reassemble the wheel make sure it is seated in the drop ( or front forks ) properly or the wheel may cockeye the disc.
Spin the wheel to double check the disc is spinning straight and true between the two pads are freely withdrawn away from the rotor. If not the non free movement is sticking the pads dragging on the rotor that will cause impossible to get the bake adjustment.
The next step is to adjust the non moving pad close to the rotor. To compensate for cable stretch screw the handlebars and caliper adjuster all the way minimum. The same Allen key is used on the single bolt wheel side on the caliper. Mind the wheel doesn't move to much or the spokes entangles the key.
Screwing inwards moves the pad inwards correspondingly outwards moves the pad away from the rotor. With the pads properly moving back into the caliper recess you can easily get a few millimeters away from the rotor with dragging on it. Keep double checking every step of the way.
Now for reconnecting the cable. Sandwich the inner wire cable between the cable bolt, pulling down the tail pushing the lever moving the pad the same distance from the rotor as the other pad tightening the bolt.
Check the freedom of movement allowing the pads to move back the millimeter gap. Tighten the bolt with only a light tug. Any more stress will start to strip the thread.
If the spring is efficiently spreading the the pads back into the caliper recesses, the recesses allowing freedom of movement to do so as you squeeze the handle bar brake lever the pads should grip the wheel with a sudden jerk stop.
The next step wire cable stretch slack can be adjusted from caliper and lever handle bar levers when the bike is back on it's wheels.
If you are experienced at internet shopping there are lots of web sits selling brake parts. Goggle Avid BB5 bicycle disc brakes. Using Goggle images will present you with a list of images of the pads and the web site companies displaying catalog and prices. You'll find you can replace both wheels for as little as 12 dollars and can be expensive as much as 50 dollars.
Rim and mechanical disk brakes are controlled by a inner wire cable sliding in the outer cable. If they don't t slide back and forth properly causes the inner wire cable dragging.
Do this simple test. Squeeze the handle bar levers feeling the squeeze of the lever observing how the pads compresses the rim. If the pads grip the rotor flush the handle bar lever should should feel solid straight away a good sign of free cable movement. When you let go of the lever the pads should retract away from the rim evenly.
Check the inner wire cable connection in the handle bar lever if the wire is frayed ready to come adrift at any time.
Check the handle bar lever cable adjuster screwed out to far causing stress on the tip of the shred pulling it towards you every time you squeeze the handle bar lever often striping both the adjuster and lever threads becoming sloppy due maximum adjustment. There are also adjusters on the brake calipers.
On the wheel side of the caliper, not the frame mounting bolts, there is two Allen key mounting bolts. These are only to be loosened just enough for adjustment only. Once loose enough by trial and error twist one direction and try the handle bar lever. If worse try the other direction. By this trial and error technique you can get the pads to move on and off from the rotor properly.
When you squeeze the handle bar lever the pads should compress both sides of the rotor flat and true.
Retighten. Watch you don't wrench the bolts. Just a light tug they can't move.
Check the pads squeezing the handle bar lever again.
Braking efficiency will also depend on how much the condition of the rotor is. So on inspection the surface should be like a new one, clean, smooth and shiny like a mirror. Examining the rotors of new bikes what they look like, should look the same an excellent rule of thumb guide.
Looking at the rotor where the light shines on a angle to you will show up a dirty rotor can get. So too the surface of the pads should look equally clean like new ones.
When assembling pads an incorrect assumption dabbing some grease behind them in an attempt to improve freedom of moment, vibration and squealing, the grease will only end up getting onto the pads absorbing it. To keep the pads and rotor clean while handling it is prudent hygiene practices while handling these parts. Pristine clean hands can be achieved cleaned with washing machine soup powder.
Spongy brakes is often deceiving one thinks of warn pads. Pads in good condition not retracting away from the rotor properly is the cause of a spongy feel. They are not necessarily that warn.
This is often caused by handle bar adjustment or modification causing changes in brake cable tension. It is also misaligned pad recesses. In both cases doesn't allow the pads to retract back into the recess housing away from the rotor properly. The steering angle tension will tend to pull on the cables.
The pads are sticking in the recesses preventing them from retracting back away from the rotor properly. If the pads do not retract back into the recesses properly when the handle brake levers are squeezed dragging on the rotor compress the rotor skewed the cause of the spongy feel.
Any modification to the handlebar arrangement will effect the tension of the brake cables effecting the pads to retract flush back into the recess away from the rotor property. In the in instructions shows how you can compensate the difference of the handle bar modification adjusting the brakes after replacing pads.
If brakes are to be replaced are fitted so the recesses are properly aligned allowing the pads freedom of movement to retract back into. As in any brake system the efficiency of the spring can effect braking performance.
A good long hard look at the rotor for any evidence of brake pad dragging ware is prudent. Evidence of brake pad ware is evidence of sticking brake pads. In other words the rotor can help determine if they are and how much possible ware is done. Don't rubyour fingers on the rotor. Be like a CSI investigator that doesn't touch crime scene evidence only look and even then handling with gloves, prongs and tweezers to prevent cross contamination transfer.
Access requires only one all round Allan key except there is no room for a key for the rear wheel brake lever because of the frame. A spanner is required there.
Gather a try, biscuit tin or low cardboard box to catch the parts as they fall to the ground so you don't lose the vital bits.
Wash you hands in clothes washing soup powder so they are pristine clean as a insurance against oily transferee. Turn the bike upside down resting on the seat and handle bars.
In the light eye the rotor running between the caliper. In perspective to the bike up side down moving the caliper brake lever downwards you'll observe the pad on the wheel side will not move while the other side moves onto the disc.
When reassembling pads make a note to resemble them so they compress the rotor flat and retract from the rotor back into the recesses properly the key to the brakes working best.
Remove the wheel.
Put the parts catcher in position to catch the bits when they drop out.
The wheel removed undo the cable from the brake caliper lever anchor bolt. Just undo enough to clear the wire cable leaving the bolt on the lever.
The same Allen key that fits the cable anchor bolt will fit the two bolts on the wheel side of the caliper. Don't be shy to put some weight on them to undo. But don't be rough unscrewing because of the aluminum threads. They must be with drawn out dead straight.
Once the bolts are withdrawn the cover comes off one or both pads along with the spring may fall into your catcher. Remember you are handling the brake pads from now on so your hands should be pristine clean to insure you don't transfer oil and crease to the oil absorbing pads and rotor.
Examining the spring is a “V” shaped spring steel spring clip each tip crumpled with a "u" shape hook that fitted in a slot in each pad. The spring was effectively sandwiched between them.
Looking carefully at the pads based on new ones observing ware will determine how close the spring will be to scrapping the rotor. It is also a good indication the pads were not really retracting back into their recesses properly causing brake drag on the rotor.
An inefficient spring can be fixed by gently bending it wider, remembering to bear in mind to be careful not to distort it that it become useless.
Reassembly is tricky as it is a bit fiddly. Fit a pad color side into the corresponding recesses in the caliper and the spring in the corresponding pad slot.
Correspondingly fit the other pad color inwards the cover recess guiding the cover hooking the tip of the spring into the hook in the slot of that pad.
Line up the cover to the threads. Careless fitting of the two bolts into theses threads here is the major cause
of stripping the caliper threads rendering it useless. Screw the bolts carefully dead straight with only fingers. Never force them with the spanner if they feel a bit tight. Carefully withdraw and jiggle the cover a bit so the bolts can finger screw with out any grinding tight feel freedom of movement.
If the spring is efficiently spreading the brakes, and you have the recesses properly aligned as you tighten the pads will retreat back into the pad caliper recesses neatly flushed. If the don't undo and reset the caliper cover so the pads do.
Check the pad freedom of movement are not stickling by moving the caliper brake lever. If the they stick loosen the bolts jiggling the cover moving the caliper brake lever until they do and tighten. The final tighten of the bolts is another area that will strip the caliper threads. Don't wrench. A light tug they can't and no more.
Keep an eye on the freedom of movement by double checking every step of the way the pads are not sticking so they are flushing back into the Caliper recesses properly.
The next step is the refitting the wheel. With the pads sitting flushed back into their recesses properly the rotor will fit between the caliper just like that finalizing the tightening of the wheel nuts or if a quick release and double check the freedom movement the pads have fully retracted back away from the rotor.
If it appears something is preventing the wheel to fit in place one of the pads or both is preventing the rotor from sliding between the two pads a sign it is catching on a pad because of no freedom of movement to retract back into the caliper recess. Double check they are not sticking by readjusting the housing. When you reassemble the wheel make sure it is seated in the drop ( or front forks ) properly or the wheel may cockeye the disc.
Spin the wheel to double check the disc is spinning straight and true between the two pads are freely withdrawn away from the rotor. If not the non free movement is sticking the pads dragging on the rotor that will cause impossible to get the bake adjustment.
The next step is to adjust the non moving pad close to the rotor. To compensate for cable stretch screw the handlebars and caliper adjuster all the way minimum. The same Allen key is used on the single bolt wheel side on the caliper. Mind the wheel doesn't move to much or the spokes entangles the key.
Screwing inwards moves the pad inwards correspondingly outwards moves the pad away from the rotor. With the pads properly moving back into the caliper recess you can easily get a few millimeters away from the rotor with dragging on it. Keep double checking every step of the way.
Now for reconnecting the cable. Sandwich the inner wire cable between the cable bolt, pulling down the tail pushing the lever moving the pad the same distance from the rotor as the other pad tightening the bolt.
Check the freedom of movement allowing the pads to move back the millimeter gap. Tighten the bolt with only a light tug. Any more stress will start to strip the thread.
If the spring is efficiently spreading the the pads back into the caliper recesses, the recesses allowing freedom of movement to do so as you squeeze the handle bar brake lever the pads should grip the wheel with a sudden jerk stop.
The next step wire cable stretch slack can be adjusted from caliper and lever handle bar levers when the bike is back on it's wheels.
If you are experienced at internet shopping there are lots of web sits selling brake parts. Goggle Avid BB5 bicycle disc brakes. Using Goggle images will present you with a list of images of the pads and the web site companies displaying catalog and prices. You'll find you can replace both wheels for as little as 12 dollars and can be expensive as much as 50 dollars.
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