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Main Area => General GS500 Discussion => Topic started by: girlracer on September 03, 2010, 04:00:06 AM

Title: Front Brake Master Cylinder Window
Post by: girlracer on September 03, 2010, 04:00:06 AM
The window on my master cylinder is breaking, I have an 04 gs500f, what years will work as replacements? and does anyone have one to sell maybe from a wrecked bike or etc.
Title: Re: Front Brake Master Cylinder Window
Post by: T1z3R on September 03, 2010, 06:50:01 AM
someone on ebay was selling them.
search the forum and you might find the link another member posted.
Title: Re: Front Brake Master Cylinder Window
Post by: erbilabuc on September 04, 2010, 08:44:32 AM
there is a company in PA I think that sells the glas replacement for 15$. I dont remember who but Buddha knows.
Title: Re: Front Brake Master Cylinder Window
Post by: AuNatural on September 04, 2010, 07:10:36 PM
If all else fails, I have a complete (nice) master cylinder for sale in the classifieds.  :thumb:
Title: Re: Front Brake Master Cylinder Window
Post by: Grease_Monkey0021 on March 15, 2024, 08:55:27 AM
I think I may have found an improvised solution to this problem by using a 16mm diameter silicone plug.

You can check it out here: https://youtu.be/gKjYFypuz2w?feature=shared

Now...if somebody wants to try this I recommend to check if the silicone plug you use will actually be brake fluid resistant. Try submerging it in brake fluid for a couple of weeks and see how it reacts.
Title: Re: Front Brake Master Cylinder Window
Post by: Rallyfan on March 17, 2024, 08:55:34 PM
Is the sight glass intended to be replaceable?

Is it a screw in type?

I'm planning ahead...
Title: Re: Front Brake Master Cylinder Window
Post by: Rallyfan on March 18, 2024, 07:12:34 PM
So I looked at my bike.

It doesn't leak, but what I suspect happened is the outer glass must have broken years ago, and all I have is a single layer inner glass left... I think (?).

In any case, I measured Φ = 17.5mm with my admittedly dodgy calipers.

Has anyone tried an 18mm sight glass replacement?
Title: Re: Front Brake Master Cylinder Window
Post by: herennow on March 19, 2024, 01:01:45 AM
Seems like Ebay is selling 4 x  18mm sight glasses for 5 bucks, probabaly worth a try.
Title: Re: Front Brake Master Cylinder Window
Post by: Rallyfan on March 19, 2024, 09:31:21 AM
Thanks, I ordered some. I also ordered a rubber stopper and will pack that on the bike just in case.

However I hesitate to do anything irreversible because I don't have a leak (yet?...).

So, two questions:

1. Has anyone gotten the 18mm pressed in OK?

2. Has anyone switched to a piss jug reservoir from another bike using the existing brake line?

Thanks!
Title: Re: Front Brake Master Cylinder Window
Post by: moe_tunes on March 19, 2024, 11:40:40 PM
 Here is a vid  (https://www.youtube.com/watch?v=u1CZBiLIZc4) of a Honda mechanic replacing the sight glass on a project bike. I like how it was his first time doing this and he wasn't happy with his first attempt.

Hope it helps.