You were lucky with your cylinder. I recently pulled one off of a K 75, which was so badly corroded that the piston was frozen into the outer housing. It’s resisted every attempt from hammering to pressing in a vice to the point where we just ordered a new master cylinder. By the way, I keep a handlebar mounted MC to use in pumping out caliper pistons and stubborn MC pistons. It usually works unless totally corroded.

Thanks for the video, it helped me rebuild my Brembo 15/16 rear for my "ran when parked a decade ago" '84 Moto Guzzi V65SP. The only thing additionally I had to do was seat the seal /tapered washer assembly with a deep socket. The barrel of the Brembo body is stepped. Also the Guzzi Brembo has a plastic piston stop which fits before/inside the spring. I got the seating procedure from a Guzzi Forum.

I'm currently working on a 82 R100RT. Your videos are so helpful, thank you!!

9:51 la ultima arandela sustituye al circlip que sujeta el conjunto dentro de la bomba, para montarla tienes que presionar el eje de la bomba hasta el final y con un vaso largo apoyar en el interior sobre la ultima arandela y golpear hasta que entre en su alojamiento

Another great video. Thank you.

Just done the job your clips are invaluable,l had much trouble getting piston out it was solid,tried your ways even blowtorch after shielding plastic nipple Finally had to drill oil feed hole 1mm bigger to get thicker drill bit in this did the trick,bore was good next problem the seal not staying in place, there's not Much on the web,but a thin wall 13mm deep socket,vice,and few taps with hammer seated it well,you did keep saying crush ring which suggested way to go Would be useful if you mentioned in clip as l can see others having issues,thanks for the informative pages

Thank you alot for the clear video and how to.

Thank-you for posting.Very clear presentation

Absolut legend! Thank you!

Nice and thorough, as usual! Nice job!

Thanks for this video, i have a solution. Nice job 👍

Excellent instructions as always. I was finding that the assembly just kept on popping out under the spring pressure. I noted the slight step inside the bore where the outer seal and stiffening ring have to push in. I found a plastic tube that fit exactly over the stiffening ring and could tap it home into its seat....not sure how you managed just to push it home?

Great videos, thank you.

Top vid....tomorrow’s first job!

I am stumped. I have the parts in correct order, but have two issues. First is, what holds the front seal washer, seal & stiffening ring from backing out? It appears to have nothing except maybe some vacuum from the piston’s action to keep it there. My second issue is that now on reassembly, (a second time), with the piston fully bottomed out, (the spring fully compressed), the actuating arm pin holes are abt. .5mm from lining up, thus I cannot get them together, and if I did, there would be ZERO movement available with the actuation are (because the piston is fully bottomed out). Darn. I’ll go attempt another reassemble & see if anything has changed.

Did you not have to press the seal/stiffener ring into the location recess after inserting the piston?

Thanks for the video,my master cylinder is a sealed unit not like this one a 1982 model,could you advise on how to open it to see if it can be restored? Thanks

Hi Brooks, how does the front seal stay inside the cylinder? Mine just keeps falling back out. Trying to bleed I had plenty of air coming through and I actually found the stiffening ring had fallen out completely when taken it apart. Thank you

I am rebuilding a R65LS front brake master cylinder, the book said to clean both holes, mine has one hole drilled through from the reservoir and one partially drilled, not through. Should there be two holes drilled through from the reservoir??

How did you removed that from the bike. I tried tday but i could not get a grib on the last bolt. Because it is behind the frame. Love your video''s great explanations keep them comming

as you know have always been watching & appreciating your videos- Is there a way to check the efficiency of the master cylinder hydraulic oil pressure on a gauge ? is there any Data available indicating how much PSI of hydraulic oil pressure must it measure on the gauge to check efficiency of the master cylinder- i have a friends BMW whose brakes need an overhaul so in order to establish the fault in either the cylinder or the calliper i thought this test could help me to diagnose the problem correctly !!! I keep learning watching your videos ! keep it up

Does anyone know if the area under the plastic nipple where the brake fluid comes in has two holes or just one? Mine has one obvious open hole, but looks like it has another. I cant tell if it needs to be cleaned out or if its just a shut hole.

If there is any noticeable pitting in the bore can it be salvaged?

Hmm its wierd the break still does not work correctly. I have the feeling that still some air Comes in some where

Hi the team! Thanks for this video! I would like to know if the piston(15.87mm) can be replaced instead of the 14.29mm? Is it compatible in this way?

hey brook, i'm trying to bleed my R100 rear brake that has a steel-braided line from the caliper to cylinder. It seems I can't advance the brake fluid from either the reservoir side or caliper side through the system. Removing the braided line from the cylinder and placing my thumb over the cylinder opening, I can feel pressure and suction when actuating the brake pedal, however no fluid travels through. Might the issue be within the cylinder or from the piston? I have not opened it up...

I need to know how to put together the front master cylinder please

Hi Brook ! I lost an e-clip and its flat washer on one side of the pin. Do you know where i could buy them. I can't find the reference ... thank you very much

Can you advise what the rebuild kit number is & where I can get one please? No joy whatsoever here in UK... thanks, Ken

Whats the extra port on the bottom of the reservoir for?