I used this forum and article along with the service manual to do the following.
Background:
The gearbox and clutch functions were very good and BumbleBerry performed flawlessly during the first months after purchasing her and prior to my maintenance. From the clutch fluid reservoir's viewing window, I could see that the DOT4 fluid color was darker than usual. But when it came to do the maintenance, I was really shocked when I removed the master cylinder cap and looked inside! Many of you know the liquid consistency of DOT4 fluid. Opening the clutch fluid reservoir was similar to opening a jar of Vaseline! with a quarter coin size amount of really brown DOT4 fluid in the middle! I was really amazed how the clutch and brake systems still performed.
Before removing and overhauling the clutch master cylinder completely, I decided to first overhaul the Clutch Slave Cylinder (CSC).
First I took pictures of the orientation of the clutch line. There's a much better photo by CYYJ.
Then, I loosened the banjo bolt using a socket wrench. This step makes it easier to later remove the clutch line when CSC is removed.
There are three bolts that hold CSC. The most challenging and infamous is the lower left bolt (looking directly at the CSC). It is behind the exhaust pipe which makes it almost impossible to use a socket/ratchet wrench. After reading CYYJ's complete instructions, I decided to give it a try and see if I can open it without removing the exhaust pipes. I used an open spanner for this one bolt and took my time. It was very time consuming because the range of rotation for the spanner was very limited, but I managed to remove it. The other two bolts were easy and I used socket wrench.
Note: when removing the bolts, make sure not to loose the Dowel Pins. It’s also a good practice to keep track of which bolt goes where.
Once bolts where removed, I removed the CSC (still attached to the clutch line). I used the clutch lever and pumped the clutch so the cylinder would come out. The last bit took a little bit of manual work, grabbing the cylinder and removing it. Make sure to have a pan under the bike to collect old DOT4 fluid.
The inside of the CSC
The cylinder housing with slave cylinder still inside.
I removed the banjo bolt, bleeding screw and lay all components apart on a towel.
They were really dirty and grimy with years of neglect.
For cleaning, I used shop towels, very soft plastic tooth brush, new DOT4 brake fluid, and non-chlorinated brake cleaner.
Make sure you have good lighting, so not to miss any small spot.
I ordered all new rubber seals, gasket, and spring. The housing and slave cylinder piston are clean and spotless.
Please note the orientation of spring and slave cylinder cup.
I also cleaned the housing thoroughly. The old gasket took a long time to remove. I used lots of brake cleaner to soak it and then used a sharp razor blade to remove it, small bit by small bit.
I also removed Clutch Lifter Rod in the center of the housing and cleaned it. Note which end sticks out and which end is inserted (I hear some guys still can’t figure it out!)
I was told that I could have changed the oil seal (the one clutch lifter rod is inserted in the last photo) without opening the clutch cover, but I didn’t bother since it looked fine.
After making sure all parts are clean and spotless, I applied DOT4 fluid on seals and inside of the housing. The housing was put back in place and bolted down. The infamous bolt took a while to tighten, using an open spanner.
After overhauling the clutch master cylinder, I refilled the clutch system with fresh DOT4 fluid and bled the system thoroughly.
Thanks to CYYJ's post, I was able to do all that, great reference.
