Front master cylinder rebuild

[pasteurized]

Hey all - I made the mistake of swapping the original master cylinder for one off a dual disc bike a couple of years ago in hopes of doing a dual disc swap. That plan fell through and I'd like to put the original back on but it seems to be shot from sitting around dry for so long. I have it off the bike (and here on my desk) but I am having trouble getting the piston out. My question is: where exactly is this circlip that I must remove before the piston will come out? I will post some pictures down below of what I am working with and hopefully I can get some pointers.









I will be ordering a new rebuild kit once I get this piston out and inspect things a little better.

Any help you can provide on this would be great!

Thanks,
pasteurized

[Suzuki_Don]

Remove the rubber boot around the piston shaft and then remove the circlip that is inside the bore. You will need a needle nose or long nosed circlip pliers to reach the circlip. It is not easy, but it can be done. If I can do it then anyone can do it.

See picture attached.

[Nessism]

You still have pieces of the rubber boot down along side the piston. Carefully dig out the old boot and the circlip will be down in the bore. You will need some very long reach circlip plyers to get down far enough to get it out.

Good luck.

[pasteurized]

Thanks for the responses, guys. I have removed the rest of the rubber boot with a dental pick. At this point I was expecting to see a circlip, but I do not. I will do my best to clean everything up and take a better look.

[robertob]

Thanks for the responses, guys. I have removed the rest of the rubber boot with a dental pick. At this point I was expecting to see a circlip, but I do not. I will do my best to clean everything up and take a better look.

There is definitely an external expanding circlip down in there. It's really buried. I was able to get it out most easily with a machinists' scriber instead of a pair of circlip pliers.

To get it back in I used a deep socket and just "popped" it into the groove.

Keep us posted

[pasteurized]

Thanks robertob! I found that there was a small round metal clip, then a white plastic ring that were covering the circlip which are not shown on any exploded diagrams that I have looked at. I was able to pry out the circlip with some dental picks without too much of a problem. Now, getting the piston out seems like it will be a hassle. Will probably need to soak it in PB blaster a while before trying to pull it out.