Bleeding brakes

[dagus]

Do I need to bleed my brakes to change my brake pads?

What tools do I need?

[ARCIE31]

I never have.
Just remove the retaining pin. Take out the pads. Push the pistons back into the caliper (Gently). In with the new pads.In with the retaining pin. Job done.
ARCIE 31

[dagus]

Thanks. That's one less tool I need to buy for now...

[brewsy]

Doug you dont have to change your fluid but if you dont know the last time it was changed this is as good a time a any..
You really dont need any tools to bleed your brakes, well apart from some clear hose which you can get from your local auto parts store.
Bleeding brakes on a bike is a one man job (as long as you arent starting from a completley dry system).
Youd be surprised how different they will feel with new liquid. Brake fluid is hydroscopic remember so over time it absorbs moisture. Water can be compressed unlike hyd. fluid which leads to lower boiling temp i.e. brake fade and 'squidgy' feeling lever..

Marc

[jaysun0ne]

if you do, make sure the fluid is the same.

if you change fluid type you should rebuild calipers (at least thats what i have been told)

[Abquid]

Replacing pads, bleeding brakes

In my experience, bleeding the brakes on the Hawk can be a time-consuming soul-destroying experience (though it always works out in the end) and I wouldn't do it unless I was rebuilding the master cylinder and/or the caliper, or if the fluid was so old and evil it was practically black!

well, maybe it's not that bad, but it always seems to take a couple of days before all air is gone and the @#$% lever is firm...

[JR]

And if you haven't done it, replace the rubber brake hose with a braded stainless steel one. Give's you a good excuse to bleed the brakes.!!!!

[nt650hawk]

Open the master cylinder oil reserve. When you spread the pistons open the oil has to go somewhere. This will make it easier. DON’T SPILL ON THE PAINT

I must suggest this for anyone. I highly recommend it. Just ask the people who know me at the track. Do you feel that your brake lever requires more pull to get the bike to stop. Is it because of the oil, brake lines, rider? Maybe... One thing I do that seems to work out best is a detailed cleaning. That's it.

How often do you actually pay attention to your calipers? Probably every time you change your brakes. Right. Look at it this way. This is one of the places that collects probably some of the finest debris and is open to water. By debris I am talking about brake dust. This stuff gets into every single nook and cranny especially the Caliper piston seals that cause the pistons not to operate properly. Most of my experience is with 4 piston calipers but this can apply to anything.
Step:
1. Take brake pads off on one side.
2. Take one caliper off on the same side you took the pads off.
3. Thoroughly Clean caliper with Simple Green and a toothbrush. Pay particular attention to the piston and seal area. This is where the culprit usually resides.
4. Squeeze the pistons into the caliper.
5. NOW FOR THE MAGIC. While watching the pistons in the caliper squeeze the brake lever a couple of times and see which piston moves. You should expect to see the pistons moving out slightly equally. What do you mean they are not. " Your brakes are not working properly" and it is not the fluid or the brake line. This just means that the one piston is doing most of the work while the others are being lazy/sticking and causing drag, thus premature pad failure, rolling resistance and lazy lever engagement.
5. NOW FOR THE FIX. "Massage the pistons in the caliper." Here you will hold the one piston that is moving and squeeze the brake lever a few times to coax the other piston out about 3/16".
6. Clean piston while out 3/16"
7. Push the piston back in.
8. Repeat to all pistons so that they all move in and out relatively easily. I usual get the pistons to shut with a snapping sound not just a tight squeeze. This can take some time. 5-10-15 min. The time invested reveals an unbelievable outcome.
9. Install caliper and brake pads.
10. VERY IMPORTANT Squeeze brake lever to seat the pads to the rotor.
11. If you have dual set up. Repeat steps above on other side.
12. AgainVERY IMPORTANT Squeeze brake lever to seat the pads to the rotor. You do not want to go out on your first ride after all this work and run into the back of a car, tree, curb, mailbox because you forgot to set your pads
First ride watch out. More brake. Well not really. Just working correctly

Man, this is easier to do than to put it into words.

[Stevenjhow]

Very nice post! You should add that to the mods/how to "stickie"

[dagus]

Wow, Gino - THANKS.

Braided lines went on a couple years ago... so I guess they were bled then?

[brewsy]

Doug, I would say that you definitely have to change the fluid.
The procedure for changing the fluid is exactly the same as bleeding only instead of getting rid of air you actually want to squeeze all the old fluid from the master cylinder through the system so only good clean stuff is in the reservoir and lines and cylinder.

Bleed Brakes:
You need
New brake fluid - DOT 4 would be my recommendation. Don't buy DOT 5 unless you know that its been in there before. DOT 5 DOES NOT mix with DOT 3 or 4!!
Bleed hose. Clear tube that fits over the bleed nipple. Get one from your car auto parts store.
Jelly jar. Catches the old fluid.
Small spanner that fits correctly on the bleed nipple.

1) Take the top off the reservoir
2) Attach the bleed pipe to the nipple on the calliper. Pour some fluid into the jar so that the end of the pipe is covered by fluid. This is so that air doesn't get sucked back into the lines from the calliper end
3) Get yourself as comfortable as poss with with one hand on the brake lever and the other holding the spanner on the bleed nipple
4) Apply a little pressure to the lever and crack the nipple a touch. If you have opened the nipple enough (but not too far!) the lever should start moving to the bar and old fluid should start coming out of the pipe into the jar
5) When the lever is almost at the bar CLOSE the nipple
6) Check the reservoir for fluid, if it is anywhere near the bottom add some more fluid. Be careful not to overfill as this stuff eats paint!
7) If you are bleeding brakes to get rid of trapped air look carefully at the bleed pipe. You will see the air trapped in suspension in the fluid and/or big bubbles. Repeat steps 4-6 til the fluid coming out of the nipple is as clean and clear as what's coming out of your new bottle
If you are just changing fluid you (in theory) wont have any air trapped so just keeping bleeding til the fluid has changed colour from the brown shitty old stuff to the new clear clean fluid.

That's it!
There really isn't any mystery to it (unless you are starting from completely dry system).
Just remember you don't want ANY air in there.

NB When you have got all the air out top off the master cylinder with new fluid and put the top back on. However remember that when you come to change your pads put a LOAD of cloth up by the master cyl. as you will force all that liquid out of the master cyl when you push the pistons back in to fit the new pads.

HTH,
Marc

[jaysun0ne]

i got the 03 brake system off a cbr what dot fluid was honda using back then? and i guess all i can do is hope they wheren't rebuilt.

[brewsy]

AFAIK pretty much all vehicles (cars and bikes) still use DOT 4.

This is a pretty good explanation of the types.

https://www.shotimes.com/SHO3brakefluid.html

Marc

[joel]

A Mityvac can make things a bunch easier- or you can get a big syringe and reverse fill the system...