NinerZero Posted March 7, 2016 Posted March 7, 2016 Hi All, I'm still new to learning the technical's of bikes, as I want to do certain things on my own, to save money by taking it to the bike shops everytime. I cleaned my brake pads this weekend, as they were squealing and therefore it begged for a clean. I removed the pads and cleaned them. However, now when I pull the brake levers, they pull a bit further back than usual. How do I go about tightening them or firming them up if possible, so it only pulls to about 1/3 maximum. This applies to my front and back brakes now. They are hydraulic brakes.
Mojoman Posted March 7, 2016 Posted March 7, 2016 Did you just take out the pads or remove the caliper as well? If you scuffed up the pads then I would also give the discs a light scuffing as well. I usually press the piston back into the caliper (be gentle, use something wood or plastic), refit the pads.Remount the wheel and tighten QR. Pull brakes until you can feel the pad against the disc and then slacken off the caliper. Release the brake lever, spin the wheel and then pull the brake lever again and then snug up the caliper bolts (while holding lever in) and it should be aligned and not catching (depending if your disc is true or not). Remember you will need to execute a few rolling stops before your pads bed into the disc again....
NinerZero Posted March 7, 2016 Author Posted March 7, 2016 Did you just take out the pads or remove the caliper as well? If you scuffed up the pads then I would also give the discs a light scuffing as well. I usually press the piston back into the caliper (be gentle, use something wood or plastic), refit the pads. Remount the wheel and tighten QR. Pull brakes until you can feel the pad against the disc and then slacken off the caliper. Release the brake lever, spin the wheel and then pull the brake lever again and then snug up the caliper bolts (while holding lever in) and it should be aligned and not catching (depending if your disc is true or not). Remember you will need to execute a few rolling stops before your pads bed into the disc again....I just removed the pads and washed them. Dried them off and put them straight back in. Didn't adjust any other screws.
Skylark Posted March 7, 2016 Posted March 7, 2016 I just removed the pads and washed them. Dried them off and put them straight back in. Didn't adjust any other screws.Washed with what? Only clean brake pads with white spirits, preferably brake cleaner. Take it for a ride round the block and carefully jam on the brakes a few times, should firm up after a while if you didn't cock anything up. Remember, if you remove your pads always put brake blocks in or don't touch the levers, uncentered pads can also make the brakes feel a bit spongy for a while.
Off_da_brakes Posted March 7, 2016 Posted March 7, 2016 Did you by any chance flip your bike upside down when you cleaned the brakes? May then be a sign that your brakes are in need of a bleed as there may be a little bit of air in the system. Speaks to Skylark's point. I'd suggest entrusting this job to your lbs.
NinerZero Posted March 8, 2016 Author Posted March 8, 2016 Did you by any chance flip your bike upside down when you cleaned the brakes? May then be a sign that your brakes are in need of a bleed as there may be a little bit of air in the system. Speaks to Skylark's point. I'd suggest entrusting this job to your lbs.mmm...I did flip my bike to remove the pads, i don't have a bike stand. Guessing its a rookie mistake.
JXV Posted March 8, 2016 Posted March 8, 2016 The pistons may have retracted a little when you removed the pads. A few short circuits of the garden and pumping the brakes a few times may restore normal feel. Another possibility is that you didnt replace the pads exactly on the same side and position they were in when you removed them. Pads almost never wear completely parallel to the backing plate and calipers are seldom secured exactly parallel to the disc so refitting the pads on opposite sides will cause their friction faces not to be an exact fit to the discs and you'll get weaker braking with more lever movement until they bed in again. To fix this more quickly you need to at least re-align the pads to the discs as described by a previous poster....loosen caliper bolts, spin wheel, gently pull and hold lever to centre the caliper and then bolt up tight. Turning the bike upside down may have allowed a bubble to move from the reservoir into the active (pressurised ) part of the brake system and it will require bleeding to restore brake performance in this case. If there is air in the system the lever will have a spongy feel. It will take initially but there will be no stopping power unless you pull much harder and the lever will move further than normal. Another cause for the symptom could be contamination of the pads. This reduces friction causing you to grip the lever much tighter than before. Common contaminants are oil and brake fluid. In either case, clean the discs with acetone (off the bike to protect your paint) and replace pads with new. Various detergents and degreasers that people use on their bikes can also contaminate pads (e.g. dishwashing liquid, engine cleaner etc.). You'll get lots of *** advice here about burning the pads in petrol, sanding them down etc. None of this is safe or guaranteed effective. If pads are contaminated with anything other than mud and grit, throw in bin and fit new after cleaning the discs. Mud and grit will come off with clean water and a toothbrush.
robsc Posted March 8, 2016 Posted March 8, 2016 Gonna try your advice JXV . I have taken out my rear pads at least 3 times to clean and sand down , they still squeal like crazy . They have been doing this since brand new , lbs said that I should replace rotor . Im not sure if this will alleviate problem though ?
JXV Posted March 8, 2016 Posted March 8, 2016 Gonna try your advice JXV . I have taken out my rear pads at least 3 times to clean and sand down , they still squeal like crazy . They have been doing this since brand new , lbs said that I should replace rotor . Im not sure if this will alleviate problem though ?Squealing is a bit different from soft levers. Key is to set the pads as parallel to the discs as possible. Some types just squeal anyway...no names mentioned Check disc wear and replace if needed. Some versions of Shimano and Avid/sram brakes come with shaped cup washers that allow you to set the caliper at a different angle to the post/adapter onto which it mounts. These can help with pad/disc alignment issues. To work correctly you need one set of cup washers above and one set below each caliper mounting tab. Follow installation diagrams to get the orientation of the washers correct. If you don't have these washers try buy or scrounge some from your LBS. You may also need a longer set of mounting bolts....
NinerZero Posted March 8, 2016 Author Posted March 8, 2016 The pistons may have retracted a little when you removed the pads. A few short circuits of the garden and pumping the brakes a few times may restore normal feel. Another possibility is that you didnt replace the pads exactly on the same side and position they were in when you removed them. Pads almost never wear completely parallel to the backing plate and calipers are seldom secured exactly parallel to the disc so refitting the pads on opposite sides will cause their friction faces not to be an exact fit to the discs and you'll get weaker braking with more lever movement until they bed in again. To fix this more quickly you need to at least re-align the pads to the discs as described by a previous poster....loosen caliper bolts, spin wheel, gently pull and hold lever to centre the caliper and then bolt up tight. Turning the bike upside down may have allowed a bubble to move from the reservoir into the active (pressurised ) part of the brake system and it will require bleeding to restore brake performance in this case. If there is air in the system the lever will have a spongy feel. It will take initially but there will be no stopping power unless you pull much harder and the lever will move further than normal. Another cause for the symptom could be contamination of the pads. This reduces friction causing you to grip the lever much tighter than before. Common contaminants are oil and brake fluid. In either case, clean the discs with acetone (off the bike to protect your paint) and replace pads with new. Various detergents and degreasers that people use on their bikes can also contaminate pads (e.g. dishwashing liquid, engine cleaner etc.). You'll get lots of *** advice here about burning the pads in petrol, sanding them down etc. None of this is safe or guaranteed effective. If pads are contaminated with anything other than mud and grit, throw in bin and fit new after cleaning the discs. Mud and grit will come off with clean water and a toothbrush.Thanks for your explanatory feedback, I'll try your advice.
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