so i got the oil, i've tried bleeding my brakes with no success the lever (in my opinion) goes too far back, not sure what i'm doing wrong, there is no air bubbles coming out the bottom when i pump the brakes, this is what i did. attach tube to the bleeder valve, pump the brakes a few times, hold, open the bleeder, close, release the lever. i don't see air bubbles coming out the bottom, yet the lever seems to go too far back? (or maybe it's supposed to be like this)?
I think you've got a leak in your master cylinder which is why you can't bleed the brakes. The picture of all the parts looks correct. The video shows you what to do and how it all goes together, he's just working on a different style master cylinder than yours, one with a remote reservoir for the brake fluid. It's exactly the same principle just a different shape. My mistake with the placement of the 0-ring in the groove, there are many different types of master cylinder, and I apologise if that led you astray. The 'snap on' ring as you call it is a circlip that prevents everything from coming out of the cylinder, I assumed, as your piston was out that you had removed it. Maybe it got broken and fell out in the accident. I would remove the internals and rebuild it as per the video, there is no need to clean out the inside of the cylinder as he does in the video unless you believe yours has got corroded in there. Once it's been rebuilt then add brake fluid, bleed the air out and see how you get on.
ok let's assume that i have a leak, that still doesn't explain why i have no air coming out the bottom when bleeding my brakes? should air bubbles come out if i have a leak? how many times should you bleed each brake? i did it 8 times ish on each brake. anyway's i'm gonna order the rebuild kit, meanwhile tho i wanna make sure i have no other issues in the breaking system. also, in the video everything is already out, how should i pull everything out on mine? does it just come out if i pull with a pair of pliers?
Hard to say. If you are satisfied that the system is bled properly then it is either fluid leakage - which you should be able to trace if you gave everything a good clean up. Take off the pads and have a good look to ensure no fluid is escaping around a piston. It could be a sh1t or defective master cylinder - either it is not capable of exerting sufficient pressure on the master cylinder piston to force brake fluid to reach a high enough pressure to force brake pads against the discs or it is defective and fluid leaks past the piston back into the main reservoir. I would be very tempted to ditch the aftermarket tat and go back to using Brembo stuff.
alright so i unbolted the oil line from the master , what was that you were saying about using a blow torch on the washers, what does that do exactly? ditch the aftermarket tat? sorry i'm not familiar with that term, what does it mean? you talking about the lever? i'd be down to buy other levers if necessary, but not the Brembo stock ones, they are an absolute blow to the eye to how ugly they look
this is what i ended up with, it seems i have everything except the ring that holds the piston in place (so in theory it should still work as the piston stay's in place even without it...
actually there is everything, even the metal ring that hold everything in place, so everything is there.... gonna take it apart and put it back in.
find some way of holding the washers - I would just use a really big screwdriver with the washers along the metal leg, so that all of the washer is visible. Then I would use a gas blowtorch to heat up the washers until they are cherry red. And then have a metal surface handy to drop them on and leave to cool naturally. I thought that it was the levers and master cylinder that were not Brembo. If the master cylinder is Brembo and you are happy that it is working properly then it should be OK. You can get Brembo repair kits, though. Might be worth it as youwould be sure that the master cylinder is OK. Dump the short levers, anyway, Fit normal length ones. They don't have to be Brembo but do need to beof reasonable quality.
would just putting the washers on a vice and then heating them up be ok? how can i test the master cilinder, it LOOKS ok, but is there a way to test it? also, this little rubber seal, which way is it supposed to be facing? i wanna make sure everything is right i watched a video showing a guy putting his finger on the end of the master, closing it, and then starting to pump to see if it builds pressure, will doing that tell me if it's good or not?
i've been at it for 8 damn hours. i'm so done, btw, i can't even find a rebuild kit for this specific model. anyone?
Using a vice will defeat the object- it will absorb the heat. The bits held by the vice will never get hot enough. You really want them lose on a metal rod or something, so that you can heat them up enough to go red. I don't know or anyway of testing the master cylinder without rebuilding, bleeding the system and checking that it can exert real pressure from the slave cylinder. You could use a piece of wood about right thickness of a disc plus two pads, to mimic it being back on the bike. Light pressure for on the brake lever should clamp the wood hard -enough so the wood cannot be moved. You can also check that you have no leaks.
Los, if I remember the video correctly I believe you have the rubber seal on the right way in the second photo but not the first. HOWEVER, in the first photo the rubber seal looks damaged, it looks as though there are holes in it. If that is indeed the case then it’s no wonder you can’t bleed the brakes. Each time you squeeze the lever the pressure can’t increase because the brake fluid escapes through the holes in the seal rather than compress within the brake lines. This would also explain why you’ve seen brake fluid leaking from the master cylinder. Don’t bother about bleeding the brake lines of air until you’ve fixed the issue with the master cylinder and it’s working as it should. If you can’t find a service kit then try and find a complete master cylinder & reservoir, there’s bound to be some on eBay. However, note the service kit will be common across a lot of different bikes with that master cylinder so do some research and try another model bike eg M750, M900. Im glad you’ve found the circlip because it’s that which holds everything in place and is necessary. The fact you have short levers is irrelevant, that’s just a style choice. Heating copper washers for reuse is with regards to the copper washers that sit either side of the banjo bolt that connects the brake like to the master cylinder. IMO it’s not 100% necessary to heat them but if you reuse them without having heated them just keep an eye on them for any leaks, 9 times out of 10 they will be fine.
the clip doesn't hold the piston inside tho, it only hold the rubber seal and the white plastic "thing" anyways i think i fixed it, no idea how, but i guess 10 hours of trying did the trick, took the master cylinder apart and put it back together. then, i put everything back on the bike, bleed the brakes, and it seems to work good now, I'M NOT 100 SURE. since it was raining and i only tested it in my garage by speeding up for like 5 meters and then breaking really hard and the brakes are really strong now, i'm gonna test it on the road tomorrow, because i might be mistaking
Do you have a photo of the circlip? Does it look exactly the same as the one in the photo of the kit you posted above? It really should hold the piston in.
For @los_serpent or anyone else who is rebuilding a PS13/15/16 master cylinder there is a very good write up here.
thank you!!! looks like i'm missing the last rubber cap! oh well well, i doesn't seem necessary as long as i'll be careful cleaning it once in a while, gonna take a test ride today and see if i fixed it
Los, I've just edited my post #52 as the rubber valve is correct in the second photo NOT the first as I initially wrote, my error. Apologies for any confusion. I'm assuming you have it on the right way now otherwise it wouldn't be working as you say it now is.
yeah all good i figured it out, i'm gonna go on a test ride today, hopefully, i fixed it! learned a lot from this, i won't have a problem working on brakes next time, this was my first ever time touching brakes so i was a bit lost... also, my wheel doesn't spin too freely, however it was like this ever since i bought it. i cleaned the disks, it can do 2 spins with a nice hard right-handed only spin, is that enough? (also considering the bike is not completely upright, i was holding the bike up with my hands with someone spinning the tire, so it won't be completely straight i guess that could also influence the spin)
@los_serpent please check everything again before you go out to test them mate, those brakes are your life fella, you want to be 100%, I know you want to fix the bike up on the cheap but don't go cheap on the brakes! Take care.
