Brake master cylinder sight-glass thing...

Is it possible to replace those things? Mine's been all hazed over and pretty much opaque for years... But now it looks like the plastic is actually starting to crumble! I scraped away a little bit with my thumbnail yesterday!

I assume if they are replaceable that Chacal will have some available. Feel free to chime in and I'll add a couple of those to my Christmas list along with the Colourtune Plug and Carb Sticks. Oh yeah... And the Coils. And some Iridium Plugs... And... And...

 

I'd like to know the same thing. I have one working master cylinder that has a nearly opaque "window". I have another master cylinder that could probably be rebuilt into working order... if someone hadn't PAINTED THE WINDOW BLACK.

Is this even possible?

 

There was (maybe is) a fellow selling crystal cut glass replacement kits on Flea-bay. I bought 3 kits but have not installed them yet (put them away so well, I don't know where they are). About $8 pop.

 

Yeah... I recall happening upon those auctions a long time ago. Probably a couple of years. I can't seem to find anything now that I need one, though! Is that the only source anyone's ever found for these annoying little lenses?

 

I've got a writeup someone did a few years ago on the process for this I can post if y'all would like -- the gist of it is you need a 16.7mm watch crystal (or 2) (can get from anyplace that fixes watches), lots of patience, and time.

 

Max X How a bout a replacement master cyl off e-bay or from Chacal?

Here's the fleabay link
http://cgi.ebay.com/ebaymotors/FRONT-BR ... enameZWDVW

30.00 is better than fighting to cobble up a fix that may or may not work.

 

Heh. I'll probably do both. I have two master cylinders that would be in good and great condition, respectively, if I could replace the glasses. As you say, though, nothing beats the security of a brand-new one while tinkering with the spares.

I wonder how one even gets the sucker into or out of that socket. Does it screw in, or is there a retaining ring of some sort? I couldn't tell.

 

It is epoxied into place. You'll need to remove the potted bead around the old "glass" to get it out. Some folks have been able to push the lens out from the rear (epoxy must have been really bad). Some others have simply destroyed the lens in the removal process. Take your pick...your in for a bit of work.

 

Well, definitely something to try on the one that had cracked and pitted glass BEFORE some !$*% painted over it with black paint. It has some other problems as well (missing/torn seals, etc.). If that one goes well, i'll fix it the rest of the way and do the other one. If not, scrap the whole project.

So I guess it's off to the jeweler's, eh?

 

How much do the jewelers charge for those watch crystals? You could just buy a cheap watch at a dollar store and get a useable crystal that way.

 

I could swear someone posted a link to a watch crystal place in one of our forums. Apparently they stock a suitable crystal and charge a resonable price. Hit the search function. Thought I had tucked that link away somewhere....

 

Altus sent me a link to this place:

Otoo Frei and Jules Borel

He says that you want 16.7mm glass or mineral glass. I think the ZEMG-167 on this page should work:

Flat Mineral Glass

VERY cheap for a package of 3. The RTV sealant is likely to cost more.

 

Yeah... I saw that auction (if it's the one I'm thinking of...) and $30 is a great price a like new master cylinder. Except that I'm in Canada and their non-negotiable Canadian shipping rates are $35 or $45. That kinda makes the deal a little less appealing.

I'll likely try the watch crystal route as I collect old timepieces so have a few connections for that sort of thing.

Thanks for all the ideas, Guys!!

 

[/quote] Yeah... I saw that auction (if it's the one I'm thinking of...) and $30 is a great price a like new master cylinder. Except that I'm in Canada and their non-negotiable Canadian shipping rates are $35 or $45. That kinda makes the deal a little less appealing.


Thanks for all the ideas, Guys!![/quote]



MaximumX,
Shipping to Canada sux sometimes. Some ebay sellers make a killing on it, others are OK.

I would also buy the master cylinder but for the high shipping :evil: I'm sure it will cost him less than $10 in actual postage & add on say $5 for the packaging etc.

 

I am just gonna chime in because I am currently using one of those replacement master cylinders from ebay. They work great and look good. No complaints so far. I can't remember if that was the only seller on ebay though. I'd keep digging and hope for somebody with better shipping rates. FYI.

 

the only trouble is
"Minimum Order Amount $15.00 Before shipping Charges are Added"
Someone needs to order 6 sets of 3 (18 lenses) and be willing to reship. 18 lenses including the 1/18th share of the UPS ground shipping (not including any CA sales tax) = $1.22 = forward postage and (re)packaging.

Who already needs multiple lenses?

 

Hey, Steve! If you're thinking about organizing a little group-buy on this I'd be in for at least three... Maybe six so I have some spares.

 

Two things - if ordering watch glass from OttoFrei, you'd probably be better with the thick glass ones (2mm thick - $2.50 each) from this page:

2mm thick Mineral Glass

The regular ones are less than a millimeter thick, and you might need multiple.

Second - another excellent source for a whole replacement master cylinder is Mike's XS

Mikes XS Brakes

Part #08-0255 is $69US, and is supposed to be a near-factory replacement for our bikes (single caliper anyway).

 

Another thing about Otto Frei. The !$^*#& site forces you to buy at least $15 of stuff BEFORE shipping and/or taxes are applied. Sucks if you just want a few freakin' lenses.

I already bought the RTV sealant. If anyone in Missouri wants me to replace your sight glass, I can buy enough lenses to make it worth our while. Otherwise, I'm going to poke around here and see if I can find a jeweler who will sell me just ONE or TWO.

 

Check with:

TimeSavers.com

They are in Scottsdale Arizona.
They have Watch Crystals that FIT the Window ...
And,
Clock faces in Glass that replace the Plastic Instrument Face Cover.

http://www.timesavers.com/

 

That was the site link I was looking for Rick! Thanks for posting it again!!!
I could be persuaded to purchase several for members pleasures or we could talk Chacal into stocking them...

 

the buying of a new master from MikesXS is the clever route One gets a complete brand new master cyl. Ever noticed how much a Yama Master "rebuild kit" alone Costs? As for the view ports these (at least on the half dozen Master Cyls in my collection) are ..all.. held in place by a flat spring C clip piece and sealed with a small o ring... No epoxy , No glue.
They are simple plastic windows.
I've taken fogged ones out and polished them up to be 90% of a brand new one.. Took me, mebe, 20 mins of my time.
It ani't Rocket Science guys.

 

Stick a new watch crystal in there and you'll have a clear view of the Cat-eye.
The trick is sealing it in place with Epoxy.

The solution is:

A Box of Toothpicks so you can use tiny amounts of Epoxy and have a fresh and clean "Spreader" every single time you apply a little touch of the product.

Once you get the Watch crystal in and the inside "Platform" sealed. You treat the Outside diameter like you are glasing a window.

Tissue and Laquer Thinner will "Wipe" a nice beveled edge.

 

Danilo has the best suggestion for a solution so far IMHO. Dan, are you aware if the MikesXS unit is set up for dual front disk?

 

They do have them for the dual-front discs - the one I posted was for the single, but the dual is #08-0265 - $79

 

What thickness should the watch crystal be?

 

Here, I've got them!!:


mc2) While you're rebuilding or even replacing your front master cylinder, you might as well go ahead and replace that dull, clouded, cracked thick plastic sight "window" that allows you to see the level of brake fluid in the reservoir. The original "transparent" round plastic window ages neither gracefully nor well over time, and becomes cloudy within a a few years. Our replacement flat mineral glass windows are the correct size, they won't ever get cloudy, and are one of those small details that you can step back, look at, and say to yourself: "Kewl".

Okay, all that's the good news. The bad news is that the old plastic seal can be a beast to remove. Sometimes, they come out all nice and easy. Sometimes, you have to struggle, and do as that classic old Pink Floyd song suggests: "One of these days, I'm going to cut you into little pieces......". You get the idea. You'll have to fight, struggle, and then win. Clean out the edges of the bore exceedingly well, and make sure that all remaining pieces and remnants of the old window and adhesive are gone before gluing in the new window.

And while you've got that old sight window out, go ahead and dig out the thin aluminum disc that lives right behind the sight window, and which restricts the view of the fluid in the reservoir. Although this disc never wears out, it does hinder you from getting a good view of the fluid level. Again, just carefully pry it out.

Finally, you'll need a good quality adhesive to install the new sight sight glass into the cylinder body. Although there are probably lots of brands of gasket-maker/sealant material that will work, we've found one that is black, easy to work with, and is impervious to brake fluid (NOTE: if you're going to try to use some gasket material that you have sitting around, make DARN SURE that you test it to see whether brake fluid attacks it or prevents it from hardening (almost none of the major gasket-maker materials have been "tested" by their manufacturers against brake fluid, since you do not normally ever use gasket-sealant material in a brake system).


HCP1074 Front brake master cylinder Glass Fluid Level Sight Window, correct size and thickness crystal-clear mineral glass. Each:
$ 5.95

HCP3120 Aftermarket black Gasket Maker, 3.8 ounce squeeze tube. Enough to do about ten thousand sight glasses! But it's the smallest size offered. I'm sure it works well in other applications. Each:
$ 5.50

 

Just wanted to chime in that the master cylinder sight glass may not be 16.7mm...mine wound up being about 1/32" smaller, so I went for the sand and polish of the original. Still looks yellow, but loads better than it was.

In other news, I have a 16.7mm watch crystal for anyone interested. 1.5mm thick.

 

If you take an exact measurement of the Inside Diameter where the Master Cylinder sight glass is mounted to the body of the Master Cylinder ... you can order a new Watch Crystal that will be an exact fit to the shouldered mounting shelf on the reservoir.

A little epoxy applied to that rim and the Watch Crystal will make a perfect fit.

I did it to the clouded sight glass on my Maxim and could not be happier ith the resulting fix.