Although a banjo bolt would work in the caliper, I did more poking around and finally ordered these parts so that I can have a line that goes straight into the caliper with a banjo bolt at the master.

The SS line has female threaded ends and comes with three banjo fittings. I'll probably use the 90 degree fitting at the master end:



At the caliper end I'll use one of these adapters so that the line goes straight into the caliper similar to the OEM setup:

Which end of the  goes into the caliper please- AN3 or M10?

Bricklayer wrote:Which end of the  goes into the caliper please- AN3 or M10?

The threads in the caliper are M10x1.0.

NOTE: POST UPDATED - SEE PICS BELOW  (date 20220929)

On my 85 K100RS I am going with this automotive hose- banjo w/ 90 degree and female M10 x 1.0 to connect to the brake pipe. Same length as the stock BMW hose.


EBay $13.82 (free shipping)   -   also at Summit Racing for $11.89 but 2 week wait. Next step- hose for the reservoir to master cyl. hose decision...


UPDATE


Seems this hose has an outward flare (as does the brake pipe on my 1985 K100RS).


Options: 1) drill an inward flare   2) Have a new pipe made to match   3) get a flaring tool and attempt to change the flare on the pipe

OPTION 2 WORKED

I just made a new rear caliper pipe. There's no brake shop in my city so I apologize for my moronic efforts online.

Bricklayer wrote:On my 85 K100RS I am going with this automotive hose- banjo w/ 90 degree and female M10 x 1.0 to connect to the brake pipe. Same length as the stock BMW hose.

Sunsong # 2204760

Good find. That should work with the metal pipe.

Installing my Chicom People's Rear Master brake Cylinder  and had a switch fail. Cleaned many times and just needed retirement, my rear brake switch on the 85 K100RS  has been ripped apart to see it's guts. Probably could re-sleeve or epoxy it back together but a quick search for an M8 x 1.0 brake light switch and voila! US$14 new w/ shipping on Ebay. A quick solder and water proofing should be all needed. Sure I am jumping the gun here as I just ordered it but my confidence is running high. 

New MAGURA Brake Light Switch Normally Closed NC Circuit 285.55 Gray tip M8x1.0






PART ARRIVED - FIT PEFECTLY

Further to posts 54 and 55: In addition to the alternative K100 rear brake line Sunsong Part #: 2204760, other alternatives are Nissan Part #: 46210AL510 or alternatively 46210AL51A, or Dorman #: H620527. It appears they are all replacement for the rear brake line of a Nissan Z350 - hope this helps those interested in this option.

While awaiting for my new rear brake hose to fit the Chicom master cylinder, I gave a shot at repairing the original BMW rubber boot seal which had a tear in it. After a  cleaning and roughing up with sandpaper I superglue a rubber band made from a bicycle inner tube around it. A brake fluid bottle cap was used to hold it together while it dried. Once dried I dabbed a small amount of silicon sealant on the inside. Primitive but seems sturdy enough.

Nice work!

Just did another conversion for a K Kronie. We had a bit of trouble getting the alternate boot to clamp in place. With a bit of grinding of the body the clamp was made to hold. Afterwards I decided to come up with a better method of fitting the boot. I couldn't get it in properly in my 3 jaw chuck but the 4 jaw worked a treat on the only spare left in stock. The supplier of my boots Glen from Stainless Steel Sleeves has retired he also re-sleeved master cylinders and had a great reputation. He will be sorely missed and was a great guy to deal with. 

          I have ordered 2 more Chicom master cylinders and have only one spare boot. I tried a few places yesterday for boots without success. So I resorted to the guy that does my brake hoses Sean from Aussie Automotive Services he went through his stock and couldn't come up with anything. However he has decided to help and has taken piccies of the boot and is trying to track down a source of boots. It's great to see good old fashioned service in action. At the moment I'm also using Jubilee clips until I can find a source of nut and bolt clips.
Regards Martin.
 

Received two new cylinders from Aliexpress, I placed the order on the 15th April received on the 27th April. They are slightly different from the previous ones that I bought. The packaging was a lot more professional the previous ones were just wrapped in bubble wrap. The newest ones were in bubble wrap bags inside sealed bags. The mounting lugs are slightly thicker and the body is marked  NISSIN. They previous ones have all stood up to the test of time so no complaints. I don't know whether these ones are any improvement. The supply hose looks the same which previously was found to be vacuum hose. Time will tell. I've also managed to source 4 more boots locally.
Regards Martin.

Looks like the master was cast from a Japanese master cylinder. I'm sure Nissin Kyogo are happy about that, but being China they will be totally screwed being able to do anything about it.

Developing countries have an advantage in using advancements in technologies. From what I have read and seen, China will buy old manufacturing equipment and molds which are considered out of spec by Japan. Then use them to create products at a lower price without the major investment to create manufacturing equipment. So when the quality goes out the commie name goes on- soapbox mode off.

Will post pics when I have more time, but my chicom retrofit failed this last trip.  Near as I can tell, the boot died, which may have led to the internals dying.  The plunger rod is stuck further in so the brake pedal linkage won't engage it anymore.

I know lots of miles have been ridden on these retrofits, but this episode has me debating whether I want to do another, or spring for oem instead.  

I never liked the look of the Chinese boot hence the machining to take the aftermarket one. I also pack silicone grease under the boot to reduce the chance of moisture ingress. One of my mates chased an OEM master cylinder in OZ the UK and I believe the US. He came up empty handed. 
Regards Martin.