I've f%$#& had it with brakes

[Nessism]

Jeff,

Is there enough brake there to move the bike? If so, my garage has more room than Dan's since he has three bikes these days...or is it four?

At any rate, I'll help if I can.

Ed

 

[salty_monk]

Ed - it's four But only 3 of them are here.

I could do with some help timing up the Falcon after putting in the new distributor & electronic ignition (should be a simple job but more difficult to juggle on your own) & I'm about this Saturday all day & Sunday until mid afternoon.....

I have both a master cylinder that "should" be ok & a set of known good caliper's (just removed from my G) we can try too ( but they won't travel because they are still full of fluid, I wanted to keep the seals wet - maybe a good thing in this case, be easier to fit & bleed).

What do you say we start out at my place if bike will travel & go from there, we can move to your better equipped one if necessary!

Considering Jeff is getting the same thing with both master cylinders I'm inclined to look harder at the caliper's at this stage & work backwards from there.

Jeff - what was the original reason for swapping out that Master cylinder?

Dan

 

[lucabond]

Don't know if this will help. I took my front wheel off to replace the tire. When it was still on and in the air I gave it a spin. It was dragging so once i had it off I checked the axle it was fine so started to look at the calipers 1 was frozen I put a c-clamp on the good 1 and pumped the other piston out. Cleaned up the caliper body and piston and put it back together. As I was bleeding it while hanging from a wire I noticed that if I moved the caliper around sorta rotated it with a clear plastic tube over the bleeder I was able to get a stream of bubbles to come out, probably trapped in the caliper and when I rotated it around was able to get them out. Its working like a charm now. I'm thinking there was a pocket of air trapped in the caliper under the brake fluid and by rotating it was able to let the trapped air escape. Worth a try in your'e case as it seemed you have tried everything else. Good luck,
Paul

 

[salty_monk]

Sometimes it helps to tap the calipers, connector & hoses with the back of a screwdriver to loosen up the bubbles of air too....

Dan

 

[J_C]

Either rebuild the master or bite the bullet and get a new one. Worst case you retro-fit.

If you read through, you'd see I've done both of these "options". I'm still where I am. I have a new MC, a rebuilt mc, new lines, and rebuilt calipers.

Believe me, I'm not taking this lightly.

 

[J_C]

Jeff,

Is there enough brake there to move the bike?

Ed, if I take it very carefully I think I'd be able to make it.

Ed - it's four But only 3 of them are here.

I could do with some help timing up the Falcon after putting in the new distributor & electronic ignition (should be a simple job but more difficult to juggle on your own) & I'm about this Saturday all day & Sunday until mid afternoon.....

I have both a master cylinder that "should" be ok & a set of known good caliper's (just removed from my G) we can try too ( but they won't travel because they are still full of fluid, I wanted to keep the seals wet - maybe a good thing in this case, be easier to fit & bleed).

What do you say we start out at my place if bike will travel & go from there, we can move to your better equipped one if necessary!

Considering Jeff is getting the same thing with both master cylinders I'm inclined to look harder at the caliper's at this stage & work backwards from there.

Jeff - what was the original reason for swapping out that Master cylinder?

Dan

I love you guys <3

Reason for swapping the MC was because I thought I had isolated the problem to the master cylinder, though Ed and I discovered the stuck caliper after the fact. Now it's "unstuck" but I still have the double pump.

I'm free any day, any time, from tomorrow am through sunday =]

 

[Guest]

Try working backwards from the caliper bleeders. First fill the MC then crack the banjo bolt. Now fit some clear hose over the left caliper bleeder with a squeeeze bottle full of brake fluid attached to it. Place some rag around the banjo area to protect your paint from the fluid. Open the bleeder and force the fluid into the caliper and back through the lines until clear fluid flows out the banjo opening. Repeat this on the right caliper. Tighten the MC banjo while the clear fluid is flowing. You have just completely eliminated air from the system from below the MC banjo, including the contensious tee fitting under the tree. Air likes to travel upwards so this system works a treat.

Check that the smaller of the two holes in the bottom of the MC reseviour is not blocked. This hole allows fluid to return from the line back to the MC after the brakes have been released. When blocked, air gets trapped foward of the piston and is difficult to expell. The blockage is not often apparant until you remove the brake lines.
It is also there to allow for natural expansion of the fluid within the brake system when the ambient temperatures rise significantly. Mine blocked and would cause the brakes to drag after the bike had been sitting in the sun all day.

Good luck.

Thank you 49er. Chef had just told me about this method last evening on the phone. Looks like I'm going to be holding off on any work for now.......


Thx Dan. I'll wait. Hopefully they'll be good enough to get me to garage day.

I guess at this point I'm on to the last thing on my list (synching and tuning carbs).

Any idea on when we can have garage day? I was hoping to get one last ride before I start my first year of Law School (which by all accounts in an unpleasant experience where time will be at a premium) but am realizing despite my best efforts this wont likely happen.

See! I do listen to you Ian!!!



Except for the airbox part

 

[salty_monk]

If you want to continue playing with the existing setup to see if you can bleed it then Ed's is better with more space than mine.... If you want to switch out parts then we'll have to do it at mine.
I'd also rather do the Falcon at mine... just in case it won't go or something afterwards, I don't want to saddle Ed with it at his place

 

[J_C]

I'm fine going to your place or Ed's. Doesnt matter to me. Though it would be nice to try swapping parts out (namely calipers) to try and hammer down the issue once and for all

Oh and I have por15 and aquarium rocks and a stopper to return to Ed, so I can bring those too.

 

[49er]

See! I do listen to you Ian!!!



Except for the airbox part

Yes, I'm impressed Bill.

Couldn't you have expressed that last sentence a little more prominently though?

 

[82Shafty]

If you read through, you'd see I've done both of these "options". I'm still where I am. I have a new MC, a rebuilt mc, new lines, and rebuilt calipers.

Believe me, I'm not taking this lightly.

Do you want to borrow a gun to lay your steed down for the glue factory?

Ok, so let me get this straight...

You had a brake problem that caused you to believe it was a master originally only to discover you had a stuck caliper? Was the lever soft, or was the brakes just not stopping the bike?

So after you installed a new master on the bike:

1) brake lever still did not pump up ( major impetus )
2) or it pumped up hard but the brakes still didn't grab? like a WTF?

It stinks that you don't have a brake pressure gauge to individually diagnose which part of the circuit is not functioning properly.

If the new master was 4 months old, I take it you had some street time with it.

Did you ever replace the o-ringed washers for the banjo fitting at the master? When you cracked the banjo bolt, you may have compromised the dowty seal . If it were simply copper, then I'd say no, but since you described the dowty; you may need a new set.

You also have to remember that whatever caused the original compromise of the system which resulted in a stuck caliper maybe causing havoc elsewhere.

 

[cbrophy22]

I bet I konw were that air is

I bet I konw were that air is

Dollars for dounuts Its in the spliter half way down the forks. try shakeing that spliter around let the air rise and then do trick I was talking about.

or get a 5 gallon bucket fill it half way with brake fluid and bleed the the hole system "under fluid"

 

[82Shafty]

Dollars for dounuts Its in the spliter half way down the forks. try shakeing that spliter around let the air rise and then do trick I was talking about.

or get a 5 gallon bucket fill it half way with brake fluid and bleed the the hole system "under fluid"

Back flushing can be messy, but I have seen it work on several occasions.

 

[J_C]

Do you want to borrow a gun to lay your steed down for the glue factory?

Ok, so let me get this straight...

You had a brake problem that caused you to believe it was a master originally only to discover you had a stuck caliper? Was the lever soft, or was the brakes just not stopping the bike?

So after you installed a new master on the bike:

1) brake lever still did not pump up ( major impetus )
2) or it pumped up hard but the brakes still didn't grab? like a WTF?

It stinks that you don't have a brake pressure gauge to individually diagnose which part of the circuit is not functioning properly.

If the new master was 4 months old, I take it you had some street time with it.

Did you ever replace the o-ringed washers for the banjo fitting at the master? When you cracked the banjo bolt, you may have compromised the dowty seal . If it were simply copper, then I'd say no, but since you described the dowty; you may need a new set.

You also have to remember that whatever caused the original compromise of the system which resulted in a stuck caliper maybe causing havoc elsewhere.

Hi there, it's always been a case where they were pumpable. I had gotten it to as point where it would function, but I stopped more slowly than I thought I should. After the new MC, Ed diagnosed that one caliper was getting stuck and wasnt working. We fixed that and it felt like it stopped better, but the system was still pumpable.

With both this and the old MC, it's requiring two pumps to get good firm lever feel that won't travel all the way into the bars. I swapped the washers with the rubber center from the banjo bolt with brass washers that came off the old MC's banjo bolt (they have diff thread pitches so they have diff bolts).

 

[J_C]

Dollars for dounuts Its in the spliter half way down the forks. try shakeing that spliter around let the air rise and then do trick I was talking about.

or get a 5 gallon bucket fill it half way with brake fluid and bleed the the hole system "under fluid"

OK CB, I'll loosen that splitter off the clamp and see if I can't give it more direct upwards travel.

 

[Headphase]

JC, get a big syringe and pump brake fluid in from the caliper (the bleed nipple).

Once you've done a couple of syringe fulls, get a cable tie, and get the brake lever right back onto the bars (leaving the brake fluid container lid loose).
Leave it overnight.
Come back in the morning and if necessary top up with brake fluid.

Make sure you cover the tank and everything with old towels or something first, just to keep everything clean.

I only do my brakes this way now, it takes no time and little effort.

 

[49er]

JC, get a big syringe and pump brake fluid in from the caliper (the bleed nipple).

Once you've done a couple of syringe fulls, get a cable tie, and get the brake lever right back onto the bars (leaving the brake fluid container lid loose).
Leave it overnight.
Come back in the morning and if necessary top up with brake fluid.

Make sure you cover the tank and everything with old towels or something first, just to keep everything clean.

I only do my brakes this way now, it takes no time and little effort.

This is variation of my method mentioned in a previous post.

You're right. It takes very little time/effort and works every time. Thats assuming that all your brake components are serviceable/in good nick, before you start.

 

[ironsheik]

This is variation of my method mentioned in a previous post.

You're right. It takes very little time/effort and works every time. Thats assuming that all your brake components are serviceable/in good nick, before you start.

I just did this yesterday after finally ordering a fork-oil syringe from Bike Bandit. I had zero luck finding a syringe locally so had to order and wait. I just rebuilt my MC and calipers and added dual stainless lines. The brakes have been bled plenty but are still spongy so I'm trying the syringe method.

What I did after a lot of trial and error was pull fluid from the reservoir into the syringe. I then took rag and covered as much of the caliper around the bleeder since fluid will leak out when you open the valve. Then I took a rubber bleeder cover, put it on the bleeder and poked a hole in it with the syringe to keep as much fluid in the valve as possible. Open up the valve slowly and *slowly* add pressure to the syringe. You'll feel it start to push fluid through the system. Go slowly as the fluid in the MC will bubble out and seriously go all over. I found out the hard way.

I did at least two full syringes on both calipers and got a tiny bit more pressure built up at the lever so I'm leaving the lever zip-tied over the weekend. Hopefully that will do the trick. I'll post a report.

 

[J_C]

OK CB, I'll loosen that splitter off the clamp and see if I can't give it more direct upwards travel.

I did this, unfortunately no bubbles.

I may do the reverse flush with a squeeze bottle or syringe tomorrow. I'm meeting up with saltymonk and maybe nessism to go over this thing one more time. With the benefit of spare parts, we should be able to isolate whether this is a parts or air problem pretty quickly.

 

[49er]

I did this, unfortunately no bubbles.

I may do the reverse flush with a squeeze bottle or syringe tomorrow. I'm meeting up with saltymonk and maybe nessism to go over this thing one more time. With the benefit of spare parts, we should be able to isolate whether this is a parts or air problem pretty quickly.

Take a closer look at the smaller of the 2 holes in the bottom of the MC. When it becomes blocked, air gets trapped forward of the piston and is almost impossible to dislodge. I used a 0.4mm jet drill to clear mine.