First couple pumps are mushy

[SmashEmUp]

When I got my 81/C the front brakes were a mess, dry and seized. I tore down both front calipers, cleaned and inspected all components (which all looked very good once cleaned up) and built them back up. The master was plastic and didn't even look worth repair, so I chucked it aside and installed a full metal housing master I bought off eBay. Went to bleed the brakes and struggled to get any pressure at all. Eventually, I somehow magically managed to get some pressure. The strange thing is the lever is completely limp on the first grab! Pull, pull and then what seems to be full pressure on the third or fourth pull of the lever. Now, I've read several threads about the best ways to bleed brakes. Pumping fluid from the bleeder up to the reservoir seems to to be the best, most effective way. Okay.... I get it. Lol! But before I run out and build or buy some kind of pump contraption, doesn't sound like that's all my problem is? My current method of bleeding is ineffective and I still have air in my system? Is it just that simple?

[shinyribs]

Your mushy lever is a sign of air in the system. You are right on that. If you keep pumping you can eventually get all the air out. Ii will work. The reverse bleed is good if you are impatient like myself.

[SmashEmUp]

Dude.... I already pumped a huge bottle of brake fluid through the system! The biggest bottle they have at O'reily's! Half on each side. Lol! How much fluid am I supposed to pump through? If it makes any difference the left side pressurizes first while the lever is still soft. Then the right side comes in and that's when I get pressure on the lever.

[shinyribs]

It's not how much fluid you put through the system,it's whether you get lucky and the air finds it's way out It's hard to force air down the lines and out the bleeder. if you dont want to spend/build a reverse bleeder ,you can always try pulling the calipers off the forks and rigging them up higher somehow. If you can get them above the master cylinder the air will want to naturally float to the top. I know this sounds goofy,but it works.

[SmashEmUp]

I was just thinking the exact same thing! And it DID look absolutely retarded in my head!! Lol

Thanks man

[TOOLS1]

Shiny has been preaching my sermon here, and doing a very good job. You can run gallons of fluid through it trying to bleed the air out the bottom, or get a $3.00 pump type oil can, and $.50 worth of vacuum hose, and bleed it it a few minutes with very little fluid. Your choice. However I will point out that a used master cylinder might not be in very good shape either.
TOOLS

[SmashEmUp]

No, no.... Not used. Bought it from one of those eBay stores. Third party? =/ But new though. And yes, you got me on the pumping from the bleeder valve. Lol! I'm going to buy one tomorrow. But the thing is..... I'm going to buy it while I'm out doing other stuff... But I don't want to have to take four wheels. Lol! Thank goodness for my good ol tank bag! I hope this works guys! Getting the tire mounted on the new, old wheel tomorrow. Brakes are the only thing stopping me from riding this sucker this weekend! I definitely won't rush it or cut corners when it comes to brakes. But I do hope I finally get to ride this thing this weekend. Lol

[shinyribs]

Tools,I learned from the best And yes,tank bags rock! Sure,it might look dorky,but at least I can run errands on my bike Your soda sure does get fizzy in there,though. Open with care...sticky tank

[SmashEmUp]

Rarely do I carry a soda! Lol! Wouldn't want to risk getting my iPad wet.  Lol! But yes, tank bags do rock! Way more comfortable than a backpack and way less ugly than a tailbag!

[SmashEmUp]

Hey Tools!! Help!! Lol! So I went to Harbor Freight this morning and bought the little high pressure oiler ShinyRibs linked in one of the other posts. Sucked most of the fluid out of the reservoir leaving just enough to be about 2mm or 3 mm above the holes. Hooked up to the left hand caliper (furthest first) and started to pump away slow and steady. Saw some fluid movement at first, but then, it just started to build so much pressure the hose wouldn't stay on my pump. Thought, maybe it's full now, let's do the right side. Pretty much the same thing. Small amount of fluid movement. Then plenty of pressure. When pumping I loosened the bleeders one half to one full turn. When I was done it filled the reservoir to about 2/3. That took most of the 9 oz bleeder. Probably 7 or 8 oz. What am I doing wrong? Or have I just not done it enough yet? Also, lever still has the same two to three limp pulls.

[TOOLS1]

Are you break lines bad? Sometimes the inside will come loose.
TOOLS

[shinyribs]

Those high pressure bleeders are strange creatures. I have only used that type, and never the oil can like Tools uses. They do seem to require alot of hand pressure to pump. I think it is because fo the check valve that is in them.Like yo have to force thru that or something. That has always made me wonder how much pressure it takes using an oil type pump. Been meaning to try that. If you pumped thru the bleeder and it got into the m/c reservoir,there shouldn't be any air in the system. Tools' idea on the brake line innards is a very good point.

[SmashEmUp]

Probably is. =(

Sent from my iPhone

On Jul 20, 2012, at 12:30 PM, "TOOLS1 [via Honda CB750'S]" <[hidden email]> wrote:

Are you break lines bad? Sometimes the inside will come loose.
TOOLS

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NAML

[SmashEmUp]

Well, I guess this gets postponed until next weekend then. I'll take the originals in and have some braided lines cut on payday. Probably a better starting point anyway.