The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Crossrodes on November 21, 2010, 09:48:10 AM

Title: Caliper Kit
Post by: Crossrodes on November 21, 2010, 09:48:10 AM

 I see that Motobins has a caliper kit which includes the pistons for 40mm Swinging ATE calipers.  I don't know what "swinging" calipers are.  Can anyone explain this.  Also it says that the size is stamped on the body of the caliper.  I don't see anything stamped on my caliper.  Am I looking in the wrong place?  My bike is a '79 with dual disks on the front.  I'm guessing that an additional, optional brake kit was installed somewhere along the line.  I'm also guessing that the ATE brakes are the original stock type.

http://www.motobins.co.uk/bmw-parts.php?model=R%20Series%202%20valve%20Twin

Title: Re: Caliper Kit
Post by: Bob_Roller on November 21, 2010, 09:57:05 AM

The larger bikes had calipers that weren't bolted to the forks legs like the R65, they were more of a 'hinged' type that could move around a bit .

The caliper rebuild parts won't come in a kit for the ATE calipers, you need the square seal for the piston, dust seal to cover the outer portion of the piston, the o-ring between the caliper halves and finally, if you want to replace the bolts that hold the caliper halves together .

Motobins states that the piston seals and dust seals are for R65's only, the R65 has smaller diameter pistons than the other bikes of the same era .

Title: Re: Caliper Kit
Post by: Crossrodes on November 21, 2010, 10:06:25 AM

Too bad...I'd like to replace those pistons.

Title: Re: Caliper Kit
Post by: Bob_Roller on November 21, 2010, 10:11:46 AM

I was wrong about the kit, it's part number : 23070, 1 kit required for each caliper .

The kit doesn't have the small o-ring that goes between the caliper halves .

Motobins doesn't stock pistons for the R65, up until about a year ago, they had stainless pistons, I sent them an email about a month ago just to confirm they don't have them anymore the response was that they weren't a good selling item and have been discontinued .

Title: Re: Caliper Kit
Post by: Rob Valdez 79 R65 on November 21, 2010, 11:23:45 PM

And Mike V. has the small o-rings for free or nearly.  He bought a big bag of them.  Talk to him.

And as someone stated here recently, any decent machine shop should be able to turn you out pistons if you take them one of yours to work from.