The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: littledave on April 27, 2013, 03:50:58 PM

Title: r65 ls master cylnder question
Post by: littledave on April 27, 2013, 03:50:58 PM
im having problems with the brakes on my bike (failed mot) they are very wooden with no feel and not much power in fact i can still make the wheel move with them on full at a push whitch is not good i have taken the caliper to bits this afternoon and all seems well (all new seals and bleed nipples)
but when i striped the master cylnder down and removed the piston to look at the seals i noticed the base plate of the resivor only has one hole and a part drilled hole next to it but it looks like in the cylimer manual shows two holes and tells you to clean both so my question is SHOULD I HAVE TWO HOLES IN THE BASE PLATE?
Title: Re: r65 ls master cylnder question
Post by: georgesgiralt on April 27, 2013, 04:46:52 PM
Yes. But one is so small it could pass for a mold defect.
Title: Re: r65 ls master cylnder question
Post by: Bob_Roller on April 27, 2013, 05:20:33 PM
While you are into a full brake refurbishment, if you still have the OEM brake lines, replace them .

Don't know what is available for you, but if you replace the lines, get braided stainless lines .

Take a good look at the surface of the pads that contact the rotor, chances are, they are shiny and glazed .

Put them on a piece of sandpaper, say 220 grit and rough them up a bit to remove the glazing, if any is present .
Title: Re: r65 ls master cylnder question
Post by: saintell on April 29, 2013, 06:17:54 AM
To make your answer a little clearer,one hole lets the fluid go down the line and the other,which is very small,lets the fluid return back into the reservoir,cheers Nev ;D
Title: Re: r65 ls master cylnder question
Post by: bruce_launceston on April 29, 2013, 07:23:17 AM
When we say very small we mean only 0.35mm diameter. Easy to block with corrosion or crud and difficult to clear. I used an insulin syringe needle as a drill and eventually got it through.
Title: Re: r65 ls master cylnder question
Post by: littledave on May 02, 2013, 03:14:59 PM
cheers lads