rebuild front master on 78

[dedede]

First post, hope Im in the right place. 2 or 3 months ago my son who in the USMC (comimg home soon its been 5 years) called me and told me he wanted to build a cafe bike, I loved it and bought a 78, fell in love with it and started wrenching. We decided to have a build off, bought him a 75. I have completely stripped mine painted the frame and I am rebuilding and reassembling the 78. tonight when taking apart the front master I can't figure out how to remove the plastic reservoir from the rest of the assembly.
I have been reading the posts here for a couple of months and can't believe the amount of knowledge and intrest in these bikes. I have had a 77 since the late 80s and at that time couldn't find certain parts.(no internet)

Thanks for any help

 

[5twins]

After you remove the couple screws that hold it down onto the MC housing, you basically just twist it off. It seals into the body with an o-ring and it can get quite crusted up with old, dried out brake fluid. In other words, it may be stuck on there pretty good. Twist it to break it free then just twist back and forth while pulling it out.

 

[pamcopete]

dedede,

I have 5 bikes from the '70's, '80's and the first thing I did with each when I rolled them into the garage was rip off the master cylinders and brake hoses and throw those in the garbage can. I replaced them with new master cylinders and brake hoses.

The calipers can be rebuilt because they are very simple devices with just one moving part and no exotic valves or passages. You can see inside the caliper cylinder and replace the only wear items, making them good as new. Not so with the master cylinder and the brake hoses that are 35 years old. You can clean them, and play with them all you want, but you can never be sure they are right.

Now, when I squeeze the brake lever on any of my bikes, the bike comes to a quick and controlled stop and I don't have to worry about the master cylinder blowing a seal..... or locking up the brakes...... I like that...

 

[dedede]

thanks for the help, next question how do you get the guts out I ordered a rebuild kit from MIKES
any help welcome

 

[5twins]

The guts are retained inside the MC by a snap ring but it's inset rather deeply. Mike's sells a special pair of right angle snap ring pliers made especially for this job. You can get it out with other tools, just not as easily.