master cylinder

[i2kdave]

I noticed that I couldn't see through the master cylinder sight glass on the '03 I just purchased, and I know it originally came from a beach area, so I figured it might be salt buildup and proceeded to scrape at it with my fingernail. I never could get it cleared up, but at one point I heard the sight glass make a cracking sound. Do I need to replace the whole thing or what? I don't know much about master cylinders, but this doesn't seem good.

[Easy Rider]

I don't know much about master cylinders, but this doesn't seem good.

As long as you can be sure there is sufficient fluid in there AND it is not leaking........quit screwing with it! :biggrin:

HOWEVER......

A 5 year old bike is probably overdue for fluid flush and replacement. The window obstruction might be on the INSIDE. O_o
Might be about due for front pads too; it is handy to do both at the same time.

[i2kdave]

I found the piston/cup set on cheapcycleparts.com for 13 bucks, should I replace that while I'm replacing the fluid?

[Easy Rider]

I found the piston/cup set on cheapcycleparts.com for 13 bucks, should I replace that while I'm replacing the fluid?

NO! Leave well enough alone. That won't get you a new case so you will still not have a clear site glass. That is not a recommended routine maint. item. It is sometimes hard to get a new piston to seat properly. The master cylinder is usually replaced as a complete unit.

Have you done your own brakes before? Bleeding out the air is sometimes tricky.

DO NOT change grades of brake fluid. Unlike oil, some different grades do NOT play well together.
Stick with what it says in the manual.

Good luck!

[i2kdave]

Oh, I must've been looking at the diagram wrong, I thought the cup and the case were the same thing. I'll just leave it alone. I have never done my brakes before. I looked it over in the service manual. Any advice?

[Easy Rider]

I looked it over in the service manual. Any advice?

That depends.
The SECOND time you change disk brake pads and bleed the fluid, it is a pretty simple process.
The FIRST time, however, can be a real BITCH if you don't have good instructions.
The one and only time I have done it was so many years ago that I forgot what I did wrong. :roll:

If you have a dealer with a reputable service dept., it should be fairly quick and cheap.

My advice for the moment is: If everything is working OK, wait until you need front pads.
Then if you decide to do it yourself, try to find someone locally who has done it before who can "coach".

[patrick_777]

I was about to suggest getting with another more maintenance-inclined rider and have a "garage day" to help you learn this. A group thing is a very good way to get learned fast.