[jimsilver]

after drilling out the two screws for the master cylinder reservoir/cup,why does the reservoir/cup remain in place? the bike is a 250n '79 but sat in a garage for 20 years say. I know i can get a complete new assembly for 35-40 quid but its just just annoying,if anyone can be bothered to get back to me i would be more than overjoyed, thanku

 

[Old Okie]

Most master cylinders I have dealt with have an O ring
that seals and holds the reservoir onto the lower part.
Some folks say to use 2 or 3 screw drivers and pry the
reservoir off the base. I have had very little success
repairing old master cylinders, I usually look for a replacement.
You might post a photo so we will know what you are dealing with.
Good luck.

 

[longdistancerider]

The cap is stuck on the reservoir? Most likely the rubber diaphragm has bonded itself to the cap and reservoir.
The plastic reservoir is stuck on the master cylinder? As mentioned a couple of screwdrivers to pry it out of the old O-rings. Beware the the reservoir may crack.
Personally I'd replace it with a new one that has the reservoir incorporated, one piece design.

Moved to SOHC Brake section

 

[opie051699]

After rebuilding three of them, I will say brute force works well. And a new reservoir is cheap, plus it goes in alot easier than it comes out.