95 k 75 and m\c

[Bmwsquirl]

I read a lot of posts.my question is I want to rebuild the rear m\c .I read multiple times it should have the number 12 on it.this is abs master cylinder there is a part number but no double digit 12 or 13 on it.I'm wanting to get a rebuild kit.thanks in advance
Be safe
Squirrel

[frankenduck]

Look here:

[Chaos]

if you're lucky you might be able to just take it apart and clean the seal and bore.  Worth a try if it's not pitted or ripped.

[Bmwsquirl]

Thanks ill recheck in the morning.

[Bmwsquirl]

All the rubber bits are dry rotted figuring m\c  is close.there is no 12 on it except for a unpainted machine piece where it meets mounting plate.all rebuilds say natural on websites.this has
Brembo 103741-20 on rubber cup and 70 4170 00 on body.is brembo and natural parts interchangeable?thanks
Squirrel

[Bmwsquirl]

Where natural comes I typed magura

[Laitch]

. . . figuring m\c  is close.

What does phrase mean, squirl—close to what?


Brick owners who intend to do mechanical work on their own Bricks should have a vernier caliper. Many are capable of measuring a master cylinder's bore opening.  I've seen rear brake cylinders without markings; they could be grey market cylinders. Regardless, the cylinder bore opening can be measured to settle this.

If you could provide photos in this thread of both sides of the brake cylinder, its bore and the faulty parts, we could get this sorted in short order. One seemingly successful alternative to repairing what you have is replacing what you have with a Chinese aftermarket cylinder that many riders apparently have found satisfactory. Mighty Gryphon can explain all that to you.

[Bmwsquirl]

Thanks

[Bmwsquirl]

L man
The rubber in the master cylinder is shot also..the newest rubber I can find on the 1995 is 1993.tearing out the abs it reads I can go with dot 4 or 5 anyone try the 5?
Be safe
Squirrel
Sorry on the slow reply

[Scott_]

I'd stay with Dot4. 

[Laitch]

. . .it reads I can go with dot 4 or 5 anyone try the 5?

I'd stay with Dot4. 

The 1994 K75 Rider's Manual has significant information concerning ABS. In the specification section of the Manual  shown below is the following recommendation for brake fluid. As Scott implies, this DOT4 fluid type has been recommended for all classic Bricks without or with ABS including the K1100 models. You can use other brands of DOT4 instead of just those listed.

[The Mighty Gryphon]

I have read somewhere that DOT 5 is not to be used in our bikes.  Best to avoid it and use DOT 4 which is easy to find and not expensive.

[Bmwsquirl]

Thanks