Brake bleed issues.

[Designer]

There may be two issues here. But it seems remote that both the Fork Oil Seal starts leaking at the same time as the Lever gets,...."squishy". Since the Fluid was found up by the upper Caliper Mounting Bolt, might there be some sort of leaking at the Caliper Banjo Fitting/Bleeder Screw when under pressure?

I check those both under pressure. No signs or trace of fluid. I cleaned everything off and I’m going to take an easy ride today to try to see if I can identify where the fluid is coming from.

Okay. Please do, tell us what you find. This is kind of a puzzlement.

[Herb]

Fork oil perhaps?

I thought I had a leaking caliper on my old Divvy once - had some strange fluid over it and some on the disc....ended up being a tom cat had sprayed on it

I have a background as an aviation mechanic so my first instinct when I see a leak is to smell it to try to identify the fluid. It is definitely not cat pee.

There may be two issues here. But it seems remote that both the Fork Oil Seal starts leaking at the same time as the Lever gets,...."squishy".

Since the Fluid was found up by the upper Caliper Mounting Bolt, might there be some sort of leaking at the Caliper Banjo Fitting/Bleeder Screw when under pressure?

I check those both under pressure. No signs or trace of fluid. I cleaned everything off and I’m going to take an easy ride today to try to see if I can identify where the fluid is coming from.

The lever will feel wrong if there is oil on the disc, however, the only time I have ever seen fork oil get on the disk was when I hit a pothole (HARD) and actully blew out a seal and oil went everywhere. BTW, the seal was already leaking...

It may be such a thing as the leak only shows up when the brake assembly gets hot from use...

[00Vs1400GLP]

Well. I just got done a 20 minute ride and there is definitely brake fluid coming out of what looks like around the outer piston seal (one of the ones I just replaced). Dammit!! Back to the garage I will have to go. Maybe it’s time to invest in the larger caliper mod. I guess that explains why I had a very hard time getting the lever to feel decent. I think I’ll try to source replacement pistons this time.

[Herb]

Glad you found the problem, sorry that it happened.

[Designer]

Well. I just got done a 20 minute ride and there is definitely brake fluid coming out of what looks like around the outer piston seal (one of the ones I just replaced). Dammit!! Back to the garage I will have to go. Maybe it’s time to invest in the larger caliper mod. I guess that explains why I had a very hard time getting the lever to feel decent. I think I’ll try to source replacement pistons this time.

Hmm. Any idea as to why this happened?

I mean,..you JUST replaced it!

[00Vs1400GLP]

Well. I just got done a 20 minute ride and there is definitely brake fluid coming out of what looks like around the outer piston seal (one of the ones I just replaced). Dammit!! Back to the garage I will have to go. Maybe it’s time to invest in the larger caliper mod. I guess that explains why I had a very hard time getting the lever to feel decent. I think I’ll try to source replacement pistons this time.

Hmm. Any idea as to why this happened?

I mean,..you JUST replaced it!

I just replaced the seals, either I got bad seals or there was some damage/pitting that I didn’t notice when I cleaned everything up. I’ll have to wait until I can take it apart to take a better look. I’m considering trying to find a known good caliper on the used market and just replacing mine. Things keep stacking up on me. I decided that the fork oil I put in was too light so I changed it to a heavier oil. When I reinstalled the fork, I cracked one of the front turn signal brackets. That is duct taped for now. On the bright side, it rides much better now.

[Designer]

I just replaced the seals, either I got bad seals or there was some damage/pitting that I didn’t notice when I cleaned everything up. I’ll have to wait until I can take it apart to take a better look. I’m considering trying to find a known good caliper on the used market and just replacing mine.

Yeah, only a disassembled inspection will tell the tale. Thos CAlipers aren't not cheap though.

Things keep stacking up on me. I decided that the fork oil I put in was too light so I changed it to a heavier oil. When I reinstalled the fork, I cracked one of the front turn signal brackets. That is duct taped for now. On the bright side, it rides much better now.

Did you Break the left or right one ?
Anyways,...here's something that you might find a help:

Right:
https://www.ebay.com/itm/402533042145?h ... SwD4FfosMF

Left:
https://www.ebay.com/itm/275257660059?e ... SwMcxiTocr




About your Fork Oil,....did the Fork Oil Actual Viscosity Chart I posted be of help? And...what Oil did you end up going with?

[hillsy]

I’m considering trying to find a known good caliper on the used market and just replacing mine.

You will probably have to rebuild whatever you buy as a replacement anyway - well at least pop out the piston(s) and inspect / clean.

I would say you either have pitting / scoring on the piston that you didn't notice or you might have nicked the new seal when you re-install the piston.

You can sand the piston to a degree - just make sure you sand around the piston - not up and down the face. Also make sure there is no corrosion inside the seal cavities.

A new piston and seal kit would still be a better option than an unknown replacement caliper IMO.

[00Vs1400GLP]

I just replaced the seals, either I got bad seals or there was some damage/pitting that I didn’t notice when I cleaned everything up. I’ll have to wait until I can take it apart to take a better look. I’m considering trying to find a known good caliper on the used market and just replacing mine.

Yeah, only a disassembled inspection will tell the tale. Thos CAlipers aren't not cheap though.

Things keep stacking up on me. I decided that the fork oil I put in was too light so I changed it to a heavier oil. When I reinstalled the fork, I cracked one of the front turn signal brackets. That is duct taped for now. On the bright side, it rides much better now.

Did you Break the left or right one ?
Anyways,...here's something that you might find a help:

Right:
https://www.ebay.com/itm/402533042145?h ... SwD4FfosMF

Left:
https://www.ebay.com/itm/275257660059?e ... SwMcxiTocr




About your Fork Oil,....did the Fork Oil Actual Viscosity Chart I posted be of help? And...what Oil did you end up going with?

Thanks, Designer. I just bought the right one. That chart did help. I went with the maxima 15. I had the maxima 10 in previously. Unfortunately, I think investigating the brakes is going to have to be a next long weekend thing.

[quote=00Vs1400GLP post_id=208485 time=<a href="tel:1654453959">1654453959</a> user_id=2245]
I’m considering trying to find a known good caliper on the used market and just replacing mine.

You will probably have to rebuild whatever you buy as a replacement anyway - well at least pop out the piston(s) and inspect / clean.

I would say you either have pitting / scoring on the piston that you didn't notice or you might have nicked the new seal when you re-install the piston.

You can sand the piston to a degree - just make sure you sand around the piston - not up and down the face. Also make sure there is no corrosion inside the seal cavities.

A new piston and seal kit would still be a better option than an unknown replacement caliper IMO.
[/quote]
I agree as long as I can find the damage and it seems to be on a piston. I won’t know until I can take it apart, so everything is on hold for now.

[00Vs1400GLP]

I just replaced the seals, either I got bad seals or there was some damage/pitting that I didn’t notice when I cleaned everything up. I’ll have to wait until I can take it apart to take a better look. I’m considering trying to find a known good caliper on the used market and just replacing mine.

Yeah, only a disassembled inspection will tell the tale. Thos CAlipers aren't not cheap though.

Things keep stacking up on me. I decided that the fork oil I put in was too light so I changed it to a heavier oil. When I reinstalled the fork, I cracked one of the front turn signal brackets. That is duct taped for now. On the bright side, it rides much better now.

Did you Break the left or right one ?
Anyways,...here's something that you might find a help:

Right:
https://www.ebay.com/itm/402533042145?h ... SwD4FfosMF

Left:
https://www.ebay.com/itm/275257660059?e ... SwMcxiTocr




About your Fork Oil,....did the Fork Oil Actual Viscosity Chart I posted be of help? And...what Oil did you end up going with?

Thanks, Designer. I just bought the right one. That chart did help. I went with the maxima 15. I had the maxima 10 in previously. Unfortunately, I think investigating the brakes is going to have to be a next long weekend thing.

[quote=00Vs1400GLP post_id=208485 time=<a href="tel:1654453959">1654453959</a> user_id=2245]
I’m considering trying to find a known good caliper on the used market and just replacing mine.

You will probably have to rebuild whatever you buy as a replacement anyway - well at least pop out the piston(s) and inspect / clean.

I would say you either have pitting / scoring on the piston that you didn't notice or you might have nicked the new seal when you re-install the piston.

You can sand the piston to a degree - just make sure you sand around the piston - not up and down the face. Also make sure there is no corrosion inside the seal cavities.

A new piston and seal kit would still be a better option than an unknown replacement caliper IMO.
[/quote]
I agree as long as I can find the damage and it seems to be on a piston. I won’t know until I can take it apart, so everything is on hold for now.

[hillsy]

I agree as long as I can find the damage and it seems to be on a piston. I won’t know until I can take it apart, so everything is on hold for now.

If you have new seals and a new piston there really is nowhere else for it to leak from (OK - the bleed nipple and the banjo bolts but they are obvious).

[Lechy]

Make sure that you orient the seal the correct way around.

[00Vs1400GLP]

Make sure that you orient the seal the correct way around.

Maybe you’re on to something. I wasn’t aware there what a correct way. Any additional info?

[hillsy]

Make sure that you orient the seal the correct way around.

Maybe you’re on to something. I wasn’t aware there what a correct way. Any additional info?

A lot of calipers will have a tapered channel for the seal which in turn angles it:



The idea being is that it promotes deformation of the seal which returns the piston to a nominal seating position.

In this instance if you remove the old seal they will appear to have a taper but new seals will be square.

Not sure if this applies to the 1400 but you will know if you look at a new unused seal compered to an old one.

[00Vs1400GLP]

Took the caliper apart today. Looked at the seal. There is a built in ridge on the outer diameter of it. The ridge is not centered on the seal so I looked in the caliper and lined up where the ridge looks like it should go so hopefully it is not in upside down. While in there I did find more corrosion deposits that I didn’t see before. The lighting in my garage is much better now. I gently cleaned it up with a wire wheel on a rotary tool. It looks better now. Everything is back together but I still need to bleed it. Wish me luck!! I’ll have time to do it later today. I’ll be sure to let you all know how it goes. Thanks for all of the helpful advice you’ve been giving me with this bike.

[Lechy]

There should be a small O-ring in there too, give it a good inspection for nicks or flat spots.

[00Vs1400GLP]

Well…. I finally got the caliper back apart and cleaned out the last bit of corrosion I saw in it. Got my test ride in and… oily residue on the brake rotor again. However, you all have led me to inspect things further. I noticed today that my right fork is leaking. I just tore the forks apart about a month and a half ago and cleaned them up and installed brand new seals. There is a bit of potting on them that I noticed today that is a bit deep. I can catch the tip of my mechanics pick in it and it looks like it goes below the line of the seal when the bikes weight is on it. I now believe that it is fork oil I am finding on the rotor. This thing is making my head hurt. For now I sanded the pits smooth with 600 and 2000 grit wet/dry, but I think I’m going to have to look around for a set of forks or at least inner fork tubes that are in good shape and not terribly expensive. I think I’m going to try to prove the brake caliper good tonight by pulling full pressure on the lever and tying it off overnight to see if it leaks. I already cleaned off the oil residue with brake cleaner so I think that’ll give me a good indication in the morning if my caliper is holding pressure and fluid in. If it all looks good, I’ll take it for a quick spin on some slow easy roads and look for signs of fork oil again. If anyone has any bright ideas on taking care of pitting on the fork tubes, I’m all ears. One day Trudy will be a road beast again. Until then, I have no choice but to chip away at the issues that pop up. Each new issue pushes back my goal of finding a cheap dirt bike or quad to rebuild though. 1 project at a time .

[Herb]

Brake fluid is water soluble. If you can rinse it off with water it is brake fluid if it takes a solvent to get it off it is oil.

[hillsy]

If anyone has any bright ideas on taking care of pitting on the fork tubes, I’m all ears.

I've heard of people filling fork pitting with filler / epoxy then sanding smooth. Never done it myself but logic says it should work....temporarily at least. It's the holes the pitting creates that rip the seals so filling the holes back to the original height fixes that.

Long term you either need to replace the fork stanchions or have them re-chromed. 2nd hand replacements would be the cheaper option.

[Designer]

Well…. I finally got the caliper back apart and cleaned out the last bit of corrosion I saw in it. Got my test ride in and… oily residue on the brake rotor again. However, you all have led me to inspect things further. I noticed today that my right fork is leaking. I just tore the forks apart about a month and a half ago and cleaned them up and installed brand new seals. There is a bit of potting on them that I noticed today that is a bit deep. I can catch the tip of my mechanics pick in it and it looks like it goes below the line of the seal when the bikes weight is on it. I now believe that it is fork oil I am finding on the rotor. This thing is making my head hurt.

I hear you about .."making my head hurt". You certainly have been "put through the wringer" here! I admire your stamina.

Question come to my mind is,...how many more times do you want to redo this Fork? Filling those "pits" and sanding them is certainly a temporary Fix,...at best. You'll soon be back in there, replacing seals/repairing AGAIN,. when The Fix fails you.


May I suggest,....this just might be a cost-effective way to obtain the Fork Tube you need:
https://www.ebay.com/itm/312139495333?h ... SwhIZa~xfL