RE: 1100GS Master Cylinder

["Clive Liddell" <cliddell@xxxxxxxxxx>]

 Hi Paige,
My 1995/6 R850R started weeping and, at that time, the "repair kit" was not
available from dealers.

I decided to have the master cylinder resleeved (with stainless steel) to a
more "standard" size (19mm - 3/4").  The job was done by a company
specialising in resleeving down the road in Durban for less than half the
price of a new master cylinder.  As I recall they machined down the piston
to fit the new bore and new rubbers.

That was several years ago and I have had no problem since, in fact it seems
to me that the brake fluid seems to retain its light colour for very much
longer than in the RT with its OE M/C.

Regards
Clive Liddell
Pietermaritzburg
South Africa
R850R
R1100RT 
===

I have a question on the rebuild,? when rebuilding the master cylinder what
do you use to hone the bore out with it?? It is very small and not even my
smallest brake hone will work.? Does anyone make a small one for it?? Also
the reason these things leak is they just use the Alum casting for the bore,
it is soft and pits easily.? Does anyone know of anyone who sleeves these
pieces of crap with a good durable sleeve?? it looks like it wouldn't be
that hard.

Paige









Dean:

 

This has not happened to me, but I'm pretty sure BMW makes a good rebuild
kit.   It's much cheaper than a new cylinder and it's not a difficult job.
Just keep it clean.and make sure you get that brake fluid off the paint
right away!!!

 

-TB  

 

Date: Sun, 8 Jun 2008 17:06:53 -0700 (PDT)

From: Dean Chowenhill <dchowenhill@xxxxxxxxx>

Subject: 1100 GS front Master Cylinder

 

My front master cylinder leaks brake fluid.  Not a lot,infact the amount of
leakage is not noticeable in the sight glass.  It leaks when riding and I
see drops of brake fluid in the hand guard.  If I ride for a long time, a
small amount of fluid actually blows back on my right saddle bag.  Also, and
probably related, occasioinaly the lever does not release all the way and
the brake light stays on.  I think this is because brake fluid is sticky and
it inhibits the return of the lever.

My question is: Should I replace the Master Cylinder for Rebuild it?
Bleeding brakes is not a problem for me.

dean