How to Replace your Brake Pads (Disc Brakes)
The basic rule to always follow when working on your bike:
Prepare. Prepare. Prepare.
This may even sound obvious but is worth saying again and again.
Read the Fucking Manual! You have to do your research before you go anywhere near your bike with the intention of wrenching. Riding is serious business so don't mess with it if you don't know what you're doing.
Everything I'll be teaching you guys, I learned at the Brake Maintenance class at Motorgrrl. I would also like to thank Adam Slade and Jason Hodrinsky for providing the expert instruction.
As I write this, Slick Rick " A Love That's True" is playing on my Spotify and I'm perpetually delighted.
We wrenching or what?
HOW TO REPLACE YOUR BREAK PADS
Riding around NYC makes me really appreciate having good brakes. All too often, I need to come to an emergency stop on the road because either, a car is driving foolishly in front of me, a kid on a bicycle wearing headphones blaring music jumps onto the road outta nowhere, or some other scenario where pedestrians, cars, and bicycles are causing hell for motorcyclists. All of these things have happened to me on the road, and there's no end in sight. Needless to say, I have come to appreciate having a really good braking system.
This is me and another student listening carefully to what Adam was saying:
Braking this frequently however, wears your brake pads and if you're not careful, you'll wear them down to the metal pad backing, you'll lose the ability to come to a stop, destroy your rotors, and probably hurt yourself pretty fuckin' bad! So don't play yourself! Change your brake pads when they need changing.
HOW DO I KNOW WHEN IT'S TIME TO CHANGE MY BRAKE PADS?
Most brake pads come with wear marks. Once the wear marks disappear, it's time to change your pads. If your brake pads don't come with wear marks, like my back brake pads, make sure they don't get any smaller than 2mm. Another rule of thumb, is to let the pad get no thinner than the metal backing.
These are front brake pads. These pads had wear marks on them so you could see where they were worn down.
EQUIPMENT AND TOOLS
Basic Socket set
flat head screw driver (Large)
( Gloves are optional, I didn't use any, as I have no manicure I need to preserve)
Small bowl of magnetic tray to hold the bolts you've removed
Think through all your steps before hand and make sure you have what you need before you get started. Please also keep in mind we did this work on a lift, and we recommend you do too!
The mechanism that holds the brake pads is called the caliper. This is what it looks like on a Ducati Scrambler.
Front Brake Caliper
There are two bolts holding the caliper to the fork. You'll want to loosen those using a breaker bar. But first, locate the cotter pins, and loosen them.
Cotter pins look this:
Remove the bolts holding the caliper in place. Remember to put them in your little bowl or magnetic tray. Your small parts can be easily lost if you're not careful.
Slide the the caliper off the disk carefully holding it with a rag, so you don't scratch your rims. Once you have the caliper off, you'll have to hold it until you're ready to slide it back on. It's heavy and will hang and pull the hoses it's attached to. Jason suggests using zip ties to tie it where you need it to sit, without the pulling. That way, you keep both hands free.The pads are held in place by a spring plate or retaining clip and pins. Remove them and add them to your tray. Here's a handy diagram of what it will look like:
This pin holds your cotter pin in place. Some pins are threaded. In this case they are not.
Remove the pins and the spring plate. At this point you've exposed the actual pads. Remove the brake pads, making sure that the new set is exactly the same as the set you've just removed. With the pads removed, you can see the pistons. The pistons are the cylindrical part of your brakes that push the pads onto your disks so that you can come to a stop.
CLEAN THE CALIPER AND THE PINS
Spray the caliper with brake cleaner. Use your shop rag to clean out the caliper and the part of the pistons that is exposed.
Use your big flat head screw driver to gently push the pistons back in so that you'll have space to fit your new meaty brake pads. BE GENTLE! You can use the old brake pads by sliding the big screw driver in between them and wiggle the pistons back in place. This will reset them until you start using your brakes again. Use the caliper grease to clean all the pins and the spring plate.
*IMPORTANT* Do not push your brake lever until your are completely done!
Insert the new pads. Replace the spring plate, the pins, and the cotter pins exactly how you took them out.
Slide the caliper back in position on the disks and re-insert the caliper bolts, screwing them in little by little until they are both "pretty fuckin' tight". If you have dual front disks, you'll do this a second time on the other side. Once the caliper is securely back in place, pump on your brakes a few times, slowly. This will push the pistons back out so they make contact with your new brake pads.
You'll want to follow these steps for the back brakes. In my case, I only had to remove one pin, to expose the worn out pads. Only one side of the pad is held by the pin, and the other sits on a lip in the caliper. In this case, I didn't have to remove the caliper from the disk. There was also no spring plate, so once I pulled out the pin, I was able to remove the worn pads for new ones, making it super easy to change the back breaks.
This is the hold where the pins go, to hold the back brake pads in place.
This is the little hole inside the pin, where the cotter pin will sit.
Here is a photo of the newly install break pads
Make sure to clean your disks with alcohol and your shop rag.
Check the rest of the bike to make sure all the other bolts are pretty fuckin' tight. Check your tire pressure. Make any of adjustments you need. I had to adjust my clutch, since it had too much free play.
Go for a test ride before hitting the road, pumping the brakes a few times so you know you did it right!
If everything is working properly, crack beer and give yourself a pat on the back! You've just successfully changed your brakes.
Big Thanks to Rahoul of @thruxton999 for the photos.
Next lesson will be on how to change your chain and sprockets.