In this video I go over stripping, cleaning and reassembling a motorcycle brake caliper. this will fix many types of the brakes dragging an seizing. Only basic tools required.
Never use sand paper or scotch, you could damage the finish on the pistons which could result in them not sealing anymore. Instead use some kind of metall polisch.
Yessss i agree. I wouldn’t try to salvage a piston that has damage or rust on its O ring mating surface. If it isn’t smooth and shiny it’s most likely going to leak! Great video anyway!
i've been told it's an easy job, however from your video i've had more assurance, as well as the seals inside the callipers i had no idea about. so to make my job 100%, i've ordered some just incase they are bad. Thank you for the clear explanation. great video
I just bought a whole new unit with brake shoes included for $30 to replace my stuck ones. Considering the lowest price I could find for brake shoes alone were $18... good deal.
great vid, thank you. I was struggling with my kid's bike getting the piston to move freely. Found out I had a bad caliper, reordered off ebay. Then the pistons would slide nicely without the seals, but would stick once I put the seals in. Had to really scrape out the crap in the seal grooves. Working great now.
For the cost of the seals I would always renew the full set. Call me paranoid if you will, but brakes are the most important part of any bike and I wouldn't chance reusing seals.
Yeah I get that, definitely not paranoid. On these calipers for example I have only found one set that were not re usable out of 20 bikes and I just ordered new ones.
I use a small bit wood like cocktail stick to clean out the seal groves and cotton bud to dry them out to get good look at cleanin progres of thos groves
This is really awesome. I don’t know why my brakes won’t retract but I guess it’s a pressure issue. I took the piston out and cleaned it and I cleaned the entire caliper and I’m just not sure if the piston is retracting all the way. Where are you adding the brake fluid and releasing air down on the caliper? Thanks!
As long as your wheel spins freely with the brake released. Common causes of pistons not retracting is dirty seals, after market lever that is holding the master cylinder slightly engaged, last is if the brake fluid resiovor has to much fluid. You add the fluid to the resiovor connected to the lever/ pedal and bleed the air out of the bleed nipple, the bleed nipple should be located at the top side of the brake caliper. Hope this helps. Cheers Logan
Hi and thank for your video. I would like to disassembly my brembo brake to clean and change seals with new one. I think to start removing the banjo in order to avoid the completely coming out of oil from the tank. This because my mv agusta has got abs and is very very difficult remove air bobble that go inside if you empty all the plant from oil. So I ask you when I unscrew the banjo (with the tank of the oil closed) do I have time to stop the oil before the tank and all the plant is empty? Thank you from Italy
What I would do in your case is when you remove the banjo bolt have the caliper higher up than the master cylinder so that gravity cannot drain all the brake fluid.
Thanks for taking the time to make a great informative video. Greetings from Fargo North Dakota, maybe you can help me with my brake caliper challenge. Have Brembo brand that has two pistons on each side of the caliper. Completely disassembled calipers and removed all pistons and seals. Cleaned everything out very well and relube before putting seals and pistons back in. Reassembled calipers and bleed brake lines with fresh fluid. Pistons still not retracting even the minuscule amount they should when not applying pressure to the brake lever. Ideas, thoughts of what I should next check? Thank you
Could be a couple things. The master cylinder could be not returning and holding pressure in the brake line. To check this simply losen off a banjo bolt and if pressurised fluid comes out instead of a slow leak, the master cylinder needs a service. 2nd make sure your front brake lever has some play and is not holding the piston in, this hapens normally when Chinese levers are fitted. Check these first and let me know how you get on. Cheers Logan
Thanks for clarifying, loosened banjo bolt at master cylinder and fluid came out readily. Almost all the Pistons were firm going back into the calipers, one was difficult even after moving seal and piston itself
Great video, really informative! I do have a kinda unrelated question. Did you as a video publisher set when will the subscribe buttion flash? at 5:32, when you say "i want you to smash that like and subscribe" the actuall "Subscribe" button near your channel name lights-up. Is that something youtube does automatically when it hears "subscribe" on video or did you somehow had to set it? Thanks
Thanks and yes when publishing a video you get to pick when the button appears.
5 месяцев назад
@@TheMotorcycleForge yeah but I dont mean ON the video. The button under video, that is right next to your channel name lights up. Watch this video in "Incognito" so you are logged out. You will see how subscribe button gets a rainbow border at precisly 5:34 It's first time I'm seeing this. And thanks again for the video! I rebuild my front brake yesterday and even though 1 poston was rusted asf I still am able to ride around for a week until brake rebuild kit comes
Hi,Its it possible, if you snap the bleed nipple off ,then after welding it over so it looks like a tooth filling ,you are able to bleed from a banjo onto the hose into caliper?
Generally the bleed nipple is higher up than the banjo bolt so air might get stuck. You may be able to do it if you turn the caliper so the banjo is at the top. I would fit a new bleed nipple if it's possible to get it out but it sounds quite stuck. Cheers Logan
Thanks for the reply,would explain why brakes still spongy after pads fitted ,garage was saying I could do with new seals in master cylinder and calipers ,at a further cost of £350 ,yet was fine before I dropped off for mot,they charged me £100 extra for the weld instead of trying to get replaycment calipper 😮
Yeah thats a bit odd, they definitely should have just got a new nipple or complete caliper. That quote for seals seems a bit extreme. I can normally get a master cylinder rebuild kit and caliper seal kit for our race bikes for under 50nzd, 25ish pound, Im fitting them myself though. Hope some of this is useful 😅 Cheers Logan
Did anybody else have difficulty putting the top smaller seal in. Mine looked like it way bigger than the groove it came out of. I tried for an hour and it would not go. I ordered a new set thinking maybe they're were stretched out.
Im relieved to know I dont need to replace the whole caliper and piston to fix front brake with aerox 155. So Instead I just ordered new sets of brake pads.
That's a good compressed video version of the job. Mine - though of course I have changed the pads a few times and bled the brakes, are now getting a bit... uneven. I would guess that the uneven feel in the lever when braking (anything more than very gently) is due to the cylinders/seals etc. not being completely clean or free of build-up and of course due possibly to worn seals... at 98,000 kilometres. Great video, man... and you stuck to the golden rule... no more tech' language than is necessary. Liked.
@@TheMotorcycleForge Thanks for replying. I do not know the term "pulse" for levers, so I will put it like this: The brakes are functional. Not much less good than they were when the bike was new. They have always been mediocre on the PCX (2015) in my opinion, though. Under gentle-to-normal braking, there is nothing untoward to notice. Under normal-to-sharp braking, and more so under sharp braking, even if the finger pressure on the lever remains constant or increases smoothly/consistently, the lever will reach a certain point, then there is a feeling that there is no increase in braking (the lever moves no father), then suddenly the lever moves farther and there is a slight increase in braking. This is probably that my finger pressure meets steadily increasing resistance (smooth caliper/piston movement) then suddenly greater resistance (rough, incremental caliper/piston movement). Hence it's time to do more caliper checking/maintenance than is necessary for a regular pad change and or break bleed. Though there is nothing complex going on in theory, I have never taken these calipers apart right down to individual component level. In addition I am a DIY/owner mechanic and not a "properly" trained one. A bit of a long-winded reply. Sorry.
Ok so the two areas I would check first is if the brake caliper is floating ( only has pistons on one side of the pads) Make sure the pins that the caliper slides on are not dry/seized use rubber grease to lube them. Second it may be that your master cylinder has worn groves/notches in the bore and the piston is catching on them causing this sticky leaver. Hope this helps, cheers Logan
@@TheMotorcycleForgeHey can I ask one more thing? Thanks... When you say "it may be that your master cylinder has worn groves/notches in the bore and the piston is catching on them causing this sticky leaver." Do you mean the cylinder in the caliper or the cylinder in the brake fluid reservoir which the brake lever contacts directly? Thanks again.
I tried todo the same but, when checking the pistons, only one of them is moving, the other just pretends to move. But when holding the one that moves freely, the the other one moves upwards. I’m puzzled as to why this is happening Also, there is no air on the system yet, they don’t work 🧐
Was the stuck piston tight when reinstalling? If so you may have pinched a seal. Or seal may be perished. There may still be air, is there any high points in the brake line?
You never mentioned how important it is to install the outside seal's with the large side inward or your brakes will just seize up and always drag , ruining your pads and rotor prematurely, not to mention, the horrible fuel mileage you will get because your basically riding around with your brakes on. 😢 RU-vid tips can sometimes cause people more damage than not. 🤔
The seals on this Caliper and most other Japanese style calipers that I have worked on are symmetrical square seals they can go either way. What bike has these seals you speak of?
