I put new seals on the front brakes on my 5th gen last year. This year I added galfer SS brake lines. I also put speed bleeders on the calipers so I could bleed the brakes without an assistant. Today I finished bleeding the system and took the bike out for a short test ride. The front brakes have good response but the rear pedal had the strange behaviour. Whenever I applied the rear and front together, the rear pedal would "push" back against my foot. When I got back to the garage I discovered this. It appears the circlip came out of the SMC (secondary master cylinder). I did take apart the SMC while rebuilding the calipers but I didn't replace any internal parts. I believe I re-assembled the SMC correctly -- the internals look the same as a rear brake master cyl.
there is the possibility to install a circlip incorrectly cuz there is a difference in shape between the top and bottom edges, one slightly radiused and the other sharp and square.
Yeah, I think most circlips are stamped metal, and the flat side is supposed to take the force. Wasn't obvious which was the flat side when I installed it.
Problem solved. I replaced the SMC circlip with one from a K&L rebuild kit. This circlip it was obvious which was the flat side. Also I screwed up when installing the new brake lines and bolted them to the wrong locations on the SMC. So I swapped those to the correct positions. Finally I found the pin bolt on the rear caliper was bent causing the rear brake to bind. I replaced that with a spare from my 2nd Gen parts stash. Now linked brakes are working as expected but the rear pedal is still soft. I ordered a cheap mityvac clone to finish bleeding the rear.
