Clutch MC rebuild

[mlindskog]

It is time for me to rebuild the clutch master cylinder again. I will get the rebuild kit in a couple of days, so no worries there. My problem is instead how to do it.

I rememeber that I have somewhere on the internet seen a very good hands on manual on how to do the rebuild. Of course I can´t remember which website it was on. Any hints or even links to the website in question will be much appreciated.

Mikko Lindskog
Norrköping
Sweden

[ducinthebay]

I haven't done one in about 25 years now, or at least since e-bay was invented. But, from what I remember,its pretty straight forward. there is some kind of retaining ring, either a simple wire hoop in a slot, or a clip that that requires the tiny needle nose pliers. There's a spring behind it, so be ready when you get the retaining ring loose. Use a digital camera to take pictures as it comes apart, so you can remember the order. DON'T WASH THE PARTS IN GASOLINE OR OTHER COMMON SOLVENT!! It reacts with the rubber and will make it swell, and nothing will work properly. Use Q-tips and brake fluid to clean everything, or a product for cleaning brake parts. Of course, wear gloves and glasses. Lay out a towel to work on, it keeps things clean, and parts don't roll away on you. Use brake fluid as your assembly lube. If you haven't got a fresh bottle of brake fluid, nows a good time to buy one. Beer when you are done.

Cheers,

[mlindskog]

Thankx for the answer! After some searching through old bike papers, I found the manual I was looking for. Luckily I had printed the thing. The funny part is that it was on the old ducatipaso.org web site under the adress

http://ducatipaso.org/maintenance/clutc ... clutch.htm

It is not there anymore. Hopefully it is somewhere on the present web site, and I just didn´t find it. If not, my suggestion is to put it there again, as it was a very useful help for rebuilding the clutch master cylinder.

just my two cents

regards
Mikko in Norrköping, Sweden

[paso750]

yeah, unluckily some things have been lost over time. Via waybackmachine I found it, but w/o the pictures. I added it to the FAQs.

G.

Clutch Master Rebuild


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Clutch master cylinder failure is characterized by a relatively sudden loss of clutch stiffness. It can give little or no warning as to its impending failure.
The procedure to rebuild the master cylinder is relatively simple, and only requires a minimum of tools. A clean space to work and some patience is most important.

You will need Ducati part 000047226, which I obtained for approximately $25us. The dealer informed me that there is a price increase on the way which could raise it as high as $60us.

The procedure for this rebuild is outlined below

WARNING
Brake fluid can damage the paint on your Paso. Have a rag under your work area at all times!

1. Drain all fluid from the reservoir.
2. Remove banjo bolt from back of master cylinder that leads to clutch fluid tube.
3. Remove choke cable from choke lever.
4. Remove 2 allen bolts that retain master cylinder/lever assembly and withdraw the unit.

Gather up the following tools (shown from left to right) and find a clean place to work. You will also need a bottle of new brake fluid.
19mm wrench
medium phillips screwdriver
medium slotted screwdriver
very small slotted screwdriver
strong pick (like a dentist uses)
14mm socket

5. Using 19mm wrench, remove the lever retaining nut from the bottom of the assembly.
6. Push out the retaining pin and remove the lever from the assembly.
7. Spin the choke lever off it's mount, and remove the mount from the assembly.
8. Remove the pushrod from the dust seal in the now exposed end of the cylinder.
9. The seal will need to be picked out as much as possible to proceed. Be careful not to damage the inside of the cylinder.
10. After most or all of the seal has been removed, the piston and spring should drop free. Take note of which direction the spring faces in the assembly.
11. The seal and plastic bushing and o-ring are retained within the assembly with a press-in ring. There is a small hole in the side of the bore behind this ring, and with careful use of the small screwdriver, the ring can be distorted enough to remove easily. Also take note of which direction the plastic bushing faces.
12. Ensure that the o-ring is also out of the bore, and lay out the parts that you removed.
13. Lay out the new parts next to the old ones and make sure that they are all there. You will need to assemble the piston with the brass washer and seal, and the piston receiver will need to be inserted into the end of the spring.
14. Carefully flush out the bore with clean brake fluid.
15. Install the new o-ring in the groove.
16. Insert the spring, receiver side up.
17. Grease the piston and CAREFULLY slide it seal first into the bore.
18. Now comes the tricky part. The piston must be compressed, while the plastic bushing, dust boot, and press-in ring are all installed. I found that the best way to do this was to slip the dust seal over the plastic bushing, followed by sliding the press-in ring over the dust boot. Now, slip your 14mm socket onto the phillips screwdriver, then CAREFULLY slide the screwdriver into the hole in the end of the dust seal. Holding this assembly together, use the end of the screwdriver to compress the piston, whereas the retention/dustboot assembly should drop neatly into place.
19. GENTLY tap (the wrench works nicely) on the socket to drive the retention ring home.
20. Remove the screwdriver and socket, and put the pushrod into place.
21. Re-install the pin and clutch lever.
22. Pour about 1/4" of new brake fluid into the reservoir, and gently prime the cylinder.
23. Re-install the choke mechanism.
24. Pour yourself a pint of Guinness, and marvel at your work!

[mlindskog]

Great!
Just some further information, Ducati themselves does not sell this repair kit anymore. One has to buy them from Brembo, at least according to the dealer here in Sweden where I bought my kit.

Mikko

[persempre907]

Mr. G., you're always valued.
I have just to rebuild the MC on my red 907...

24. Pour yourself a pint of Guinness, and marvel at your work!

I prefer a good frozen lager beer.


Ciao

[mlindskog]

So, job done. Haven´t poured fluid into the system and tested it yet though. And yes, I changed two things: I didn´t tap gently to get the stuff in place, used more force, and I had a Pilsner Urquell instead of the Guiness.

regards
Mikko

[persempre907]

I had a Pilsner Urquell instead of the Guiness.

Excellent choice
Ciao

[JoKing]

Cool.
Now i found this "how to". Today. Thanks G

I finished the clutch cylinder yesterday, but i don`t mind. Maybe i have to rebuild it again, we will see... the manual attached to the kit by Brembo was for another type of cylinder. I do not know, if i put the main seal in the right way... or maybe upside down...

The most complicted thing was to get out the wire ring which holds the seal and the other plastic ring down. After i moved it a bit, i found the hole for the pin...

Jo