Front Master Cyl,..... UGLY !!

[KCinSB]

'93 K110RS: Bike's been sitting awhile (guess why) Anyhow, the front brake master Cylinder has gotten worse. I had been ignoring the 1st symptom, which was/is the lever does not return completely by it's own spring return force. Yes, it is not a good thing, and the brake will drag if not nudged back to the release position. Likely will take some Guff, but I'd gotten used to it and was even kinda liking the "hill holder" effect. Now, the Master looks so bad I assume I REALLY need to take action. Photos attached.
  Does this look like it may be saved, or not worth even looking at that option?  Is this type Master Cylinder available? Checked at my local K-Bike independent owner shop hoping for a decent used item, he has several parts bikes but each was different! Even a '93 RT was different, dunno why. I believe my bike is an import, as it has some features that point to not from a USA dealer (headlite lens for one), but that's just a guess. What am I in for here??       ??

[frankenduck]

Since a new one from BMW costs $530 (Part 32722352190) it is worth trying to save it.

More info if you scroll down here:
http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/master.leak/master.leak.htm

(My K1100RS had a sticky front brake lever when I first bought it.  I rode it home up the coast from Malibu and the hill-holder effect was very useful in San Francisco.)

[KCinSB]

MORE Ugly!!
   Well,......... things were going fairly well until I got to the dreaded Lever Pivot Screw! That thing goes through about 3/4" of alloy, then through the lever, and then into it's thread. That long shaft in the alloy must be corroded. It was hard to break loose, but did unthread, stopped moving out, and exposed the head. Could not screw it back in to work oil up into the hole, so stuck with this issue. Used a vise grips on the head with a screw driver in attempt to wedge down force on the screw while moving it back and forth. No Joy. Results so far are a messed up screw, and no progress OUT! Sprayed it good with oil, and hope it frees up....   

[frankenduck]

You're not the first to have issues with that brake lever pivot bolt. (I think it's a crappy design.)

There's a nylon sleeve on it that must expand over time or something.

The bolt is upside down in this parts diagram but the nylon sleeve is #6 here:
https://www.realoem.com/bmw/enUS/showparts?id=0532-USA-11-1993-89V2-BMW-K_1100_RS_0522,0532_&diagId=32_0784

When putting things back together I usually sand that sleeve down a bit and put lots of spray silicone lube on it in case I ever need to remove it again.

[KCinSB]

Thanks, didn’t know about the sleeve of course. So there’s more to the issue I guess. Starting to think that the indications so far are pointing to saving it may be a lost cause.  We’ll see……….

[KCinSB]

From the Max BMW site, detail on the parts:  items 5 and 6.
As advised, it looks like there is a plastic/Nylon sleeve intended to be a lever pivot point “anti-friction”. My guess is when trying to remove the bolt, that sleeve follows the bolt and hangs up on the alloy body hole. Likely the more you force it, the more the sleeve “crumples” and becomes more lodged in place! Not going to be very likely saved.

[KCinSB]

I always draw a blank using a search function. It’s got to be in here somewhere. How to remove the twist grip so the master cylinder can slide off the handle bar? Mine is also a heated grip…….  The BMW factory shop manual sucks!

[Laitch]

I always draw a blank using a search function.

Searching is something that's learned, like motorcycle maintenance. 

Within this post by frankenduck is a link to a pdf of front brake service instructions made by frankenduck for the benefit of humanity.
http://www.motobrick.com/index.php?topic=343.msg10133#msg10133

Here is a post by rbm also made for the benefit of humanity, including The Mighty Gryphon, describing servicing including grip removal.
http://www.motobrick.com/index.php?topic=6737.msg46106#msg46106

[frankenduck]

In order to disconnect the heated grip wiring under the tank you'll need to use a pin to pop the terminals out of the connector since both sides' heated grips are in the same four pin connector.

And BEFORE you pull the HG wires through the handlebars tie a string to the terminals so that it gets pulled through when you pull the wires.  Then you can use that string to pull the wires back through the handlebars when reassembling.

[KCinSB]

Thanks for the info on the grip. I had success today, and was able to get that bolt out! So now will try to clean it up and save the original part, and do not need to remove the grip to get the Master off the bar. Inside of cylinder looks like a “maybe”. I’ll try if and see.