It goes without saying that your brakes are important. I would say second only to tyres for safety importance. Therefore it also goes without saying that you must look after your brakes. Here are a few things that you need to regularly check/do on your stoppers to keep them in tip top condition.
1.) Brake Pads
Your brake pads are the part of your brakes that do most of the ‘stopping’ work. They grip the brake disc and provide friction which acts against the spinning wheel to slow you. Brake pads must be in good condition for you to stop well, so they must be regularly checked for wear. You usually don’t need to take anything apart to do this, you can just check them by looking at the wear groove / lip on the edge of the pad. If you look where the disc enters and exits the calliper you’ll see what I mean. If you can’t see a groove or lip on the pad material (on either edge of the pad), then they need replacing.
2.) Brake Discs.
Brake discs provide the other half of the stopping force in your brakes, they spin with the wheel and are slowed when the pads grip them. They too, like pads, need to be checked for wear and they usually have a minimum thickness stamped on the disc carrier (bracket). If your discs fall below the minimum thickness, then they need replacing. When you fit new discs, you must also fit new pads so that the old pads don’t score or damage the new discs. Don’t worry though because I doubt you’ll need to replace brake discs until the bike has done at least 10,000 miles.
3.) Brake Lines/Hoses.
Your brake hoses transmit the force provided by your fingers on the brake lever down to the pistons in the brake calliper via hydraulic fluid. They need to be regularly checked for cracks or leaks, and some people prefer to replace their rubber hoses for braided steel hoses. (See fitting braided hoses FAQ) This is often a good idea because rubber brake lines don’t last all that long and can become soft meaning that some of the force transmitted through the lines is lost when the hoses flex.
Strip and clean
So now you’ve checked all of these things but your brakes still don’t seem to be doing what they ought to. The next thing to try is to strip and clean the callipers. If you are unsure of doing this then you must get somebody who is sure to talk you through it or do it for you. There’s no messing around when it comes to brakes. The writer or anybody else other than the reader (you) cannot be held responsible for any loss damage injury or any other bad thing that comes of following this guide. You have been warned.
OK. One of the first things you need to buy beg borrow or steal is a torque wrench. The second is a Haynes or other workshop manual to find out the torque settings for your brakes. Got those? Good. Now you’ll need a ball of string, some copper grease and a can of spray brake cleaner (Halfords is a good bet) (blimey it’s like writing for Blue Peter). Whilst you do this DO NOT TOUCH THE BRAKE LEVER it could have some extremely expensive consequences. Also on twin disc systems only ever do one side at once… believe me it makes life sooo much easier!
First you need to loosen the pad pins which should be visible on the back edge of the calliper. Next, remove the calliper bolts which hold your calliper onto your fork legs. Ok now ease the calliper off of the disc, being careful not to twist, bend or otherwise damage the brake hoses. Now get a piece of string and tie the calliper so that the brake hoses are not under any tension (to the mudguard or something). Now remove the pad pins and catch the pads as they drop out of the bottom of the calliper.
Hooray, you’ve successfully learned how to take it all apart… what now?
Well you need to check the pads for wear, if they’re okay and they’re not contaminated with oil or something, then you need to put them in a safe place. Away from where you are working. And anything Oily.
Spray brake cleaner liberally over the inside of the callipers and all over the pad pins. If your pad pins are corroded, then they may need replacing, or you could give them a good seeing-to with some very fine emery paper.
There is often a small springy bit of metal that is stuck inside the calliper at the back. This is the pad spring. Make note of which way round it goes and pull it out carefully. Spray that with brake cleaner too and behind where it was in the calliper. Right, now comes the Science bit. Concentrate:
Copper grease is slippery. Therefore you DO NOT want to get any on the brake pad or on the disc. You’ll never get it all off and you’ll have to buy new pads and discs.
Ok preach over. Once everything is dry and you’ve given it a going over with an old toothbrush to remove any bits of crud, you can open the copper grease and put a small amount around the pistons in the calliper. Once you have done this you must push the pistons back inside the calliper housing with your fingers so that about 1mm of piston is showing above the calliper body. Yeah I know its messy, but just bear with me will you? Ok. Now you can put the pad spring in place and smear a THIN LAYER of copper grease on the prong like bits on the spring. Now put the spring back in place. OK. Now go and find your old pads or open up your nice spangly new EBC HH brake pads.
Again carefully smear a thin layer of copper grease onto the bits of the pad that are going to be pushed by the piston (I.E. the back). Usually on pads that aren’t new there’ll be ring marks on the back of the pads. Use these as a guide, and on sliding (2 piston) callipers (Most NSR’s I expect, old CBR600s, SV650s and believe it or not the new Yamaha Fazer – Yikes!) You’ll have one pad that’s not pushed by pistons but rests against one side of the calliper. Wack a small amount of grease on the centre of the back of this pad too. Your pads might have some metal plates on the back, these are called anti squeal plates and they need to stay in place.
Now grab one of the pad pins and put some copper grease on the smooth part.
OK, now put the faces of the pads together so that they touch each other, (careful your hands are bound to be all greasy; hold the pads by the back plate) and put the 2 pads back into the calliper. Grab the pad pin that you just covered in grease and push it into its hole. Jiggle the pads around a bit until the pin goes right through. Now grab the other pin and smear it in copper grease. Bung it through the other hole in the calliper. OK. Now Pull the two pads apart (its probably best to wash your hands before you do this) and slide the calliper onto the disc.
Jiggle it into position and replace the calliper bolts. Once they are tightened to the correct torque setting you need to tighten up the pad pins to the specified torque. Wohoo! You’ve just stripped and cleaned your brakes!! Not quite. One more IMPORTANT thing is (once you’ve done both sides on a twin disc system) is to pump the brake lever until it no longer comes back to the bar. That would have been fun if you’d ridden the bike like that wouldn’t it??
OK now you’re ready for a road test. BE CAREFUL on your road test, just in case you’ve forgotten, overlooked or generally ignored something that could prevent your brakes from working. If you’ve just fitted new pads or discs then you’ll need to take it easy for a few miles to let them bed in properly.
Taken from Bike Chat Forums