I've been working on a 75 CB550F for about a year now. It was a barn find and my first ever project bike. One of the many, many issues it had was the front brake, it simply didn't work. The bike had been sitting for at least 15 years. I figured the master cylinder needed to be rebuilt so I bought a rebuild kit from Dime City awhile back. I put the front brake on the back burner until the engine was working well enough to actually need brakes. But in the meantime I had installed clip-ons and ordered shorter brake lines from Slingshot Cycles.
Well, today I had some spare time (waiting for new points to arrive) so I decided it was time to swap out the brake lines and get a better idea of what the problem was with the front brake. The reservoir has had old fluid in it ever since I got it, so I thought I might as well try to bleed it like normal and see what happens.. nothing. (keep in mind I'm a bike brake newbie) So I decide to just remove the lines and catch whatever fluid spills. After removing the lower brake line I pulled the lever and fluid poured out as expected. This makes me think that maybe the master cylinder is working fine? It doesn't leak, it's been holding fluid for at least 15 years, and seems to operate normally before the caliper so maybe it's ok?
Since it wouldn't bleed through the caliper when I attempted does this mean the caliper is the problem? Is it possible the pistons that push the pads are just stuck from sitting so long? Just hoping to get a more knowledgeable opinion on this before I dive in. Thanks guys for any input.
