Nervous about brakes...

[52Chevy]

My rear brake seems fine although I do plan on looking at it a bit closer I do not want it to go out on me. It is my front brake that I worry about. The pain is gone on the fender underneath one of the brake lines. So for the time being I have no front brake. I am new to brake work other than changing pads and very uneasy about what I should do. When it comes to stopping you can never be too careful.

I know I can rebuild or replace. I have looked into both a little bit on ebay and Mikes, not sure which would be the better route, especially without looking further into what I have. I have searched through some old threads and still have these questions.

So I guess my question is this, how hard is it to rebuild brake calipers?
What are the chances of me messing up so bad my brakes fail suddenly?
How do I determine whether I need a new master cylinder and or rebuild?
Ditto for a calilper?

 

[jd750ace]

So I guess my question is this, how hard is it to rebuild brake calipers?

Not hard. Get online manuals here. http://www.biker.net/650_service/650service main.html
What are the chances of me messing up so bad my brakes fail suddenly?
Almost none, as long as you make sure they work properly before you go riding after maintenance.

How do I determine whether I need a new master cylinder and or rebuild?
Take them apart. See manuals above. If the parts are corroded and pitted, they need to be replaced, if not re-seal them. Do both of them, and replace your hoses. It's a 32 year old bike and probably has 32 year old hoses.

Ditto for a calilper? See above.

 

[52Chevy]

Thank you, I kind of figured that, but was very unsure.

I have read about stainless caliper pistons, are the advantages really that drastic?

 

[osteoderm]

These (XS650) brakes aren't difficult to rebuild; they have relatively few parts, are straightforward in design, and all the relevant rebuild parts are available.

Even if you ultimately decide on a replacement over a rebuild, it's a good idea to tear your old brakes down, if for no other reason than to learn how to do so, and to see how everything in there goes together and works.

The only real trick is to be scrupulously clean and to avoid damaging any sealing surfaces. You will inevitably find all sorts of "brake jelly" in there, along with random alloy pitting. As long as the actual sealing surfaces are smooth, round, and clean, along with the lands (the grooves that the seals fit into), then you should be good. Arm yourself with some tiny scraps of scotchbrite, a few bamboo skewers, and a dentist's pick or two, then get in there and ferret out all the gunk. Wash with the cleanser/solvent of your choice, but finish up with a final flush of brake cleaner.

In the slave cylinders, the piston forms the sealing surface, and may be replaced as part of a comprehensive rebuild. In the master cylinder, the seals/lands are on the piston, so the bore of the master forms the sealing surface; this is only replaced by replacing the whole assembly.

If you can pump and bleed the system without any leaks, all the torque specs are respected, and the moving brake parts operate smoothly without binding (silicone grease is your friend, but keep it off the pads!), then you're good to go.

If anything looks too sketchy during tear-down, like crumbling or bent lands, scored pistons, or pitted sealing surfaces, just replace it.

 

[52Chevy]

Thanks for the insight osteoderm, I will definitely keep all of that in mind when I get to tearing it all apart.

Sounds like I will be doing a rebuild. Maybe later this week I will get everything torn apart and see what I need to finish the job.