Brake & Clutch Master Cylinder Sight Glass Replacement

[dingy]

Would anyone be interested in the purchasing of replacement sight glasses for the Brake & Clutch master cylinders?

 

I know that there are some of these that have discolored or leaked in these older bikes.

 

I have just finished replacing both of my sight glasses with a mineral glass watch crystal.

 

I wanted to powder coat my master cylinders. To do this, I needed to remove the sight glass as it would not take the heat of the curing process. In doing so, I destroyed the sight.

 

I have replaced both of these now with the watch crystal. I used quick setting jewelers 2 part epoxy to bond into housing.

 

I had to buy 3 crystals & the epoxy to meet suppliers minimum order. I have had the extra crystal soaking in brake fluid for several days now. It shows no signs of discoloration.

 

If I could do a bulk purchase, it would cost $12.00 for two crystals, including shipping to you.

 

If you wanted, I could also get the two part epoxy for another $5.00.

 

I know these work on 1st gen bikes, but I am not sure about 2nd gens.

 

The crystal I used is 17.5 mm dia., & 2mm thick.

 

1st picture is of old sight removed & O ring that is under it.

 

2nd picture is of installed crystal.

 

Let me know if interested.

 

 

Gary

 

 

 

 

[Guest seuadr]

i would have a concern with the brake fluid having a reaction with the epoxy, does it seem to hold up?

[dingy]

i would have a concern with the brake fluid having a reaction with the epoxy, does it seem to hold up?

 

 

From what I have been able to locate on the internet, Epoxy is brake fluid resistant.

 

I have not yet tested the epoxy for a reaction to brake fluid though.

 

I have mixed enough epoxy to fill a bottle cap half way up. I will let it harden over night. In the morning I will remove epoxy plug from bottle cap, and submerge in brake fluid.

 

Gary

Edited March 5, 2010 by dingy
add testing of epoxy paragraph

[SaltyDog]

Gary,

 

 

It's another fine mess you have gotten me into! Just when I thought I had the bike ready for warm weather riding, you show up with another kit to fix something I had blissfully ignored. My sight glasses on my '83 standard are really in need of this repair if it proves to be reliable.

 

Please keep us informed when you are confident with the components that make up the repair kit. I would really like to be able to see the fluid level in my clutch and brake master cylinders again...

[Condor]

Sigh... Day late and a dollar short... Story of my life. I just bought a set of very clean clutch and brake master assemblies with clear sight glasses off Ebay to replace those on the '83. They were getting to look and feel like swiss cheese.... However I am tempted to pick up a set of the crystals just because. Gary, let me know if you need to add a few more to a batch.

[MiCarl]

In the XJBikes forum they've been replacing the sight glass with a watch crystal epoxied into place for years. I've heard of no problems with the fix.

[dingy]

i would have a concern with the brake fluid having a reaction with the epoxy, does it seem to hold up?

 

From what I have been able to locate on the internet, Epoxy is brake fluid resistant.

 

I have not yet tested the epoxy for a reaction to brake fluid though.

 

I have mixed enough epoxy to fill a bottle cap half way up. I will let it harden over night. In the morning I will remove epoxy plug from bottle cap, and submerge in brake fluid.

 

Gary

 

 

I have had brake fluid in the clutch master cylinder for a week now.

 

There is no sign of any degradation of the epoxy cement.

 

The watch crystal is still clear as glass.

 

The epoxy slug also looked OK. It finally ate through the plastic lid I had it submerged in brake fluid.

 

Gary

[Yammer Dan]

Sounds like a good thing. I just want to see that 1st Gen you are bringing back.

[dingy]

Sounds like a good thing. I just want to see that 1st Gen you are bringing back.

 

 

This is what it looks like so far.

 

Gary

 

http://i1007.photobucket.com/albums/af193/gdingy101/PICT5384as.jpg

 

 

http://i1007.photobucket.com/albums/af193/gdingy101/PICT5382as.jpg

 

http://i1007.photobucket.com/albums/af193/gdingy101/PICT5383as.jpg

[Yammer Dan]

Going to be nice. Why did you decide to change the engine? I have a thing about those 1200's.

[86er]

I would be interested in the "kit" when you get it together.

God....I love a good kit! Especially a good sebenteen dolla kit!!!

 

[vmaxman]

Here is some more info on site glass replacement.

 

http://www.newrivercyclesalvage.com/sight%20glass.html

 

http://wiki.sabmagfaq.org/Site_glass_replacement

[bongobobny]

OK I just ordered 18 of them. Anybody need one PM me...

[6m459]

Hi,

 

I did similar glass replacement on my red bike last fall. This bike came to me with severely deteriorated sight glasses. One was actually breached and the other was quite swollen and ready to breach any moment.

 

I used a gasoline proof gasket silicone as my bonding agent. I checked with the mfg first and they said brake fluid would be no problem for this product.

 

I did the job while the reservoirs were still on the bike. I think I loosened the fixing clamp to rotate the reservoir around the handlebar a bit to get gravity onto my side.

 

I cut my own glass disk for the first one but that was enough of that! I bought a bunch from a jewelers supply house in California. This was well worth the price given the difficutly of cutting my own.

 

The ones I bought are a bit smaller diameter than I would have gone for with the benefit of hind sight. I bought them based on measurements I took anticipating not removing a metal insert that holds the OEM ones in place. For some reason I had to remove this metal insert which made the available diameter of the recess a mm or so bigger. All in all though, the ones I have worked fine just aren't 100% optimal.

 

It was a bit fiddly getting a neat job but it turned out OK. I cleaned out the recess where the glass sits and put the adhesive in there with a small spatula. Then I pushed the glass in and let the silicone displace to take up the gap. I wished I had used slightly less than I did as there is some excess on the inside but I am OK with it.

 

Holding the glass while I did this was the fiddly part. The solution I found was to use some clear shipping tape to fashion a flap that I could hold on to. To do this I took a piece of tape and folded it over on itself for about 3/4" but kept the sticky ends free which I stuck to the glass with the flap protruding at the centre line of the glass. I then cut the excess around the circumference of the glass. This worked very well. I hope I have described it clearly enough.

 

Its been standing all winter with brake fluid in and no leaks so far as I have seen.

 

I still have several glasses left over so give me a shout if you want a pair.

 

Hope this is of interest and helpful.

 

Brian H.

Edited March 19, 2010 by 6m459
fussing about grammar

[GigaWhiskey]

I would like a pair of something and the epoxy. I have JB Weld over one of the holes because it was leaking it was so bad. I had been hoping a resolution to this had been found. I had even been tempted at buying new MC's.

 

I have not seen the brake fluid level through the site glass's for prolly 14 years.

[6m459]

Well I have to report that one of my repaired sight glasses is leaking after a ride today.

 

I haven't had time to do a full post mortem on this yet but am suspicious of the silicone product I used to bond the glass into place and the size of the gap, as I used a slightly smaller than optimal diameter glass disk.

 

I'd like some suggestions from others about the known good epoxies to use.

 

Thanks,

 

Brian H.

[dingy]

This is a follow up on the Jewelers Epoxy I used to install the watch crystals in my master cylinders.

 

I was having brake fluid leaking out of the back of my clutch master so I pulled it off today. The leakage was not from around the crystal, but from the rear of the plunger.

 

When I removed top from master, the fluid was not clear inside. It should have been due to master being rebuilt and new clutch flex lines installed.

 

I found that the epoxy that had squeezed out from around the crystal on the liquid side had deteriorated. This squeezed out material was due to my using to much epoxy when I seated the crystal in the housing. There were a few firm but pliable pieces of the excess epoxy in the bottom of the reservoir. The crystal is still tight in the housing and I could not push it out with my finger.

 

It has been in the Synthetic brake fluid for about 2 1/2 months now, so it seems this type of epoxy is not suitable.

 

I am not sure if the deteriorated epoxy led to the master leaking or not. I have a double clutch spring in and there is a lot of pressure on the handle when clutch is depressed.

 

I replaced the master with the another one I had and bled new fluid through the system.

 

The only ingredient I can find listed on the hardener tube is called Mercaptan Hardener.

 

The only ingredient I can find listed on the resin tube is Epoxy Resin.

 

There is a picture in my first post of this product.

 

Gary

[Condor]

I am not sure if the deteriorated epoxy led to the master leaking or not. I have a double clutch spring in and there is a lot of pressure on the handle when clutch is depressed.

 

Gary, Some thoughts... If the crystal isn't leaking then the 2 part isn't the problem. Usually the proper mix of epoxy:hardner is 5:1 for a good cure. The slag that was pressed out when you seated the crystal probably didn't harden completely before adding the synthetic fluid. The only thing that would allow leaking at the back of the master is a weak crush washer. The doubled up spring in the clutch in the clutch might have caused a marginal crush to fail from the extra pressure.

[dingy]

Gary, Some thoughts... If the crystal isn't leaking then the 2 part isn't the problem. Usually the proper mix of epoxy:hardner is 5:1 for a good cure. The slag that was pressed out when you seated the crystal probably didn't harden completely before adding the synthetic fluid. The only thing that would allow leaking at the back of the master is a weak crush washer. The doubled up spring in the clutch in the clutch might have caused a marginal crush to fail from the extra pressure.

 

By crush washer, do you mean copper washers on banjo bolt I assume?

 

It's leaking at the lever side, not the banjo bolt side.

 

Gary

[Condor]

By crush washer, do you mean copper washers on banjo bolt I assume?

 

It's leaking at the lever side, not the banjo bolt side.

 

Gary

 

Since you weren't real clear on where it leaked.... then yeah under the banjo.... But if it's leaking on the cup side, it's either a bad cup or a scared barrel....

[jasonm.]

The glass is to be epoxied to the aluminum. Did you remove the excess powder coat prior? Brake fluid can remove powder coat....somethimes. Also JB quik weld can handle brake fluid....I believe

[dingy]

Since you weren't real clear on where it leaked.... then yeah under the banjo.... But if it's leaking on the cup side, it's either a bad cup or a scared barrel....

 

I pulled the piston out of the leaking master today and the cylinder wall is fubared.

 

It has metal degradation in the cylinder bore directly under inlet hole. I don't know if this was caused by the epoxy I used to install the sight glass. It is rather apparent though, I don't think I would have missed it when I was rebuilding it. It is more than just grooves in wall. More like pitting.

 

It started leaking very slightly out the lever end. Replaced it yesterday. Cylinder bore is beyond honing by appearance.

 

The powder coating is not being affected by the synthetic brake fluid, there is no paint peeling even with direct, long term contact.

 

Gary, Some thoughts... If the crystal isn't leaking then the 2 part isn't the problem. Usually the proper mix of epoxy:hardner is 5:1 for a good cure. The slag that was pressed out when you seated the crystal probably didn't harden completely before adding the synthetic fluid.

The epoxy I used was 5 minute set time. I let it harden 24 hours prior to filling with fluid.

 

Gary

[6m459]

Hi,

 

I have re done the sight glass installation in my red bike's brake reservoir. This one, you may recall, had been repaired using a watch crystal and blue gasket silicone, but the repair didn't last due to bad adhesion of the silicone to the alu of the reservoir.

 

This time I used a friction fit instead of any bonding agent.

 

I had accidentally bought my watch crystals a bit on the small side, a problem when I used silicone as I had a lot of space to fill, but which ultimately seems to have worked out in my favour for this method.

 

I went to the local auto supply store and bought a roll of gasket paper. I selected a thickness of paper that would just exceed the diameter of the opening in the alu reservoir, when two thicknesses were added to the diameter of the watch crystal.

 

I very carefully cut a piece of the gasket paper that was about 1/2 to 3/4 of an inch wide by the exact circumference of the watch crystal. I then rolled the paper into a tube around the crystal and an appropriately sized matching outer diameter hex socket. I put tape on the roll, out over the hex socket, well clear of the crystal. I arranged the watch crystal so that it was just slightly in from the end of the paper roll, say 1/16" or so.

 

I then introduced the excess paper, that over hung the crystal, into the hole in the alu reservoir and then gingerly applied force, with my vice, across the back side of the reservoir and the outer end of the hex socket. This pressed the watch crystal into place, dragging the paper in with it, compressing it slightly as it went.

 

I then used an xacto knife to slice away the excess paper, flush with the alu and the glass.

 

I had the drive end of the hex socket away from the crystal so that the force was applied only to the outer edge of the glass by the business end of the socket, and no force was applied to the centre surface of the glass. (I had previously tried using a piece of birch dowel in place of the hex socket, but lost that crystal, I surmise, as the forces were applied all across the face of the glass as I pressed it in and it broke as it seated.)

 

I arranged for the seam of the paper tube to be at the 12:00 position on the reservoir sight glass hole. I think I wiped a smear of the blue silicone over that join spot after installation was complete but I don't recall for sure if I did or just thought about it.

 

The repair has held back the fluid for about a month now give or take and I have a few miles on that bike since. I am not 100% happy with the evenness of the seating of the crystal but I can live with it. Some paper bunched up a bit unevenly on the inside stopping the ingress of the crystal as I pressed it in. I am sure this is an issue with my technique that I would overcome if I did this everyday.

 

Hope this is of interest and that I have expressed myself clearly,

 

Cheers,

 

Brian H.

[thor68372rockon]

Hey Guys I Just Found A Method Alot Of People Around Lincoln, Nebraska Are Using. The Watch Crystal Is An Excellant Idea, They use "PERMATEX" "Brand Spray Adhesive PART # 82099" This Info Comes Straight From Permatex Corporation. I Had A Buddy At O'Reilly Auto Parts Call Them Up And They Said The Brake Fluid Will Not Degrade This Sealing Spray At All. They Recomend Getting A Piece Of Watch Crystal The Same Size As The Opening In The Cylinder And Putting An O-Ring The Same Size As Cylinder Opening. Scuff Area With Emory Cloth Or Suitable Abrasive Material For Good Adhesion Of Spray Sealer, Then Clean Area Well With Paint reducer Or Mineral Spirit Making Sure To Not Get Any Inside The Cylinder, Put O-Ring In First, Then Put Watch Crystal In On Top Of O-Ring, Then Put Tape On The Top Of Crystal, But Only In The Center Where You Don't Want The Spray Sealer To Cover Crystal (So You Can See Your Fluid Level) (Leave A Tab Of Sorts Of Tape On Top For Easy Tape Removal) Then Spray PERMATEX Sealer Over Inside Edges Of Crystal And Cylinder Opening. Don't Know If You Can Put On 2 Or 3 Coats Or Not, I Would Think So. A Little Pressure On Crystal To Seat Against O-Ring While Drying Would Probably Be A Good Idea For Optimum Sealing. I Hope This Helps, I Just Rebuilt The Clutch Cylinder To Find That The Sight Glass Had A Hole In It And A New Cylinder Would Cost $90 Some Dollars. I'm Going To Try And Find Some Watch Crystals The Right Size And Give This A Go Monday. I'll Keep You All Informed. Does Anybody Know Where A Good Place To Buy Watch Crystals Would Be?? Thanx!!

[thor68372rockon]

@dingy

 

Did You Try Honing Your Master Out With A Cylinder hone Or A Small Bottle Brush Hone? It May Take Out Enough To Still Be Usable. Have Done It In The Past On Automotive Rear Wheel Cylinders That Had Set For Over A Year And Have Been Sucessful In restoring Them to Usable Condition. Hope That Helps Bud.

Thor68372rockon:sign Rock On: