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Prowling Tiger
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2,048 Posts
Discussion Starter #1
I changed the nasty brake fluid today. During the procedure, I let the fluid get too low in rez and introduced air into system. I have worked on restoring proper pressure; however, the lever still feels too squishy even though the brake operation is much smoother than before. The lever gets within a 1/4 inch of grip before brake kicks in. The pressure is great enough to where I cannot touch the lever to grip.

So question, is their an easier alt. to restoring pressure other than the normal bleed procedure?

Thanks!
 

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Chasin' the blacktop
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1,498 Posts
but most of us don't have a pump for reverse bleeding. You can try using a turkey baster with a long airtight tube to help suck fluid and air from the bleed fitting. I've done it on hard to bleed cars and it actually worked. Have one person gently squeeze the brake while you slowly let the baster suck on the bleeder fitting as you open and close the valve. For some reason the light vacuum seems to get the air bubbles to move better.
 

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Prowling Tiger
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2,048 Posts
Discussion Starter #4
but most of us don't have a pump for reverse bleeding. You can try using a turkey baster with a long airtight tube to help suck fluid and air from the bleed fitting. I've done it on hard to bleed cars and it actually worked. Have one person gently squeeze the brake while you slowly let the baster suck on the bleeder fitting as you open and close the valve. For some reason the light vacuum seems to get the air bubbles to move better.
I took the bike for a quick run and the brake operation seems to be much better than before. I could lock up the front if I wanted too. In comparison to my Dad's 1500, my brakes kick much later than his. His lever only moves slightly while mine stops at about 1/4 inch from the grips.

I thought I read on here that letting the bike sit over night with the brake lever tied down would force the air bubbles towards the bleeder valve. IS this true?
 

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Banned
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2,190 Posts
Yes blaz, gravity bleeding should work. Do not seal the reservoir, and do not let it low enough to uncover the port.
 

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Super Moderator
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2,570 Posts
My brakes where much like yours blaz after a fluid change (and cleaning out crap from master cylinder).

I tied brake handle back over night a couple times, helped some. but I think the biggest improvement just came over time.. as the air bubble worked its way out of the system (back to the master cylinder I can only assume, as I did no further bleeding)
 

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Prowling Tiger
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2,048 Posts
Discussion Starter #7
My brakes where much like yours blaz after a fluid change (and cleaning out crap from master cylinder).

I tied brake handle back over night a couple times, helped some. but I think the biggest improvement just came over time.. as the air bubble worked its way out of the system (back to the master cylinder I can only assume, as I did no further bleeding)
Ah, ok. Well, I'm not concerned at this point. The brakes work and that's all I care about.
 

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Premium Member
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267 Posts
Look up speed bleeders online, they are awesome. you can do the whole job alone and in minutes, including changing the fluid annually, which I do now because it's so easy. They are made in Illinois and replace your current bleeder fittings. There is a check valve inside so you don't have to open and close them manually while bleeding the system.
I like it so much I put them on all my vehicles.
Bronson
 

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Just a regular guy
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833 Posts
Ok., so about 2 weeks ago I decided to change the fluid in my brake system... like an idiot I let the fluid get to low... now I have zero pressure at the lever. I have tried everything short of reverse flow bleeding. I have tied the lever, bought the one man bleeder from Advance Auto, everything... The weather is beautiful and I want to ride!!!

The brakes worked great before I messed with them, so I guess my question is... how come I have NO pressure? A little air shouldn't cause this much trouble...
 

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Dr. Vulcanstein
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1,536 Posts
Ok., so about 2 weeks ago I decided to change the fluid in my brake system... like an idiot I let the fluid get to low... now I have zero pressure at the lever. I have tried everything short of reverse flow bleeding. I have tied the lever, bought the one man bleeder from Advance Auto, everything... The weather is beautiful and I want to ride!!!

The brakes worked great before I messed with them, so I guess my question is... how come I have NO pressure? A little air shouldn't cause this much trouble...
You didn't.strip the.bleeder valve did you? It doesn't take much to over torque them and the slightest air leak will cause problems.
 

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Just a regular guy
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833 Posts
I hope not.....


What's the best way to check?
 

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..have a vulcan good day!
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4,508 Posts
Ok., so about 2 weeks ago I decided to change the fluid in my brake system... like an idiot I let the fluid get to low... now I have zero pressure at the lever. I have tried everything short of reverse flow bleeding. I have tied the lever, bought the one man bleeder from Advance Auto, everything... The weather is beautiful and I want to ride!!!

The brakes worked great before I messed with them, so I guess my question is... how come I have NO pressure? A little air shouldn't cause this much trouble...
Years ago I had the same issue....ended up doing a Drip Bleed (overnite) to resolve.
Then had issues with lever not returning 100% to engage Brake Light Switch....
The small pin hole in the Reservoir (allows air into reservoir replacing pumped fluid) was plugged up (located @ brakeline connection).
EDIT: After thought, maybe the Pinhole plugged is causing initial issue ? ? ? ?
hth

:smiley_th
 

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Dr. Vulcanstein
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1,536 Posts
I hope not.....


What's the best way to check?
A little dish soap or thick liquid around the thread base while pumping the lever. If its leaking you'll see bubbles, might even here a hiss. Sometimes the yoke behind the horn might need tightening, and sometimes holds an air bubble, that's another thing you can check.
 

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Super Moderator
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2,570 Posts
I tied my brake lever back for a day. that seemed to help.

over time, my lever has gotten more solid, appearently as whatever air bubble it had migrated out of the way
 

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Just a regular guy
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833 Posts
Ok, so I tried reverse bleeding... no improvement. I crimped the hose coming out of the master cylinder and that gives me pressure so I know it isn't the m/c. I crimped again and took out the bleeder valves.. the treads do look kinda fund\ky, but not stripped. I reinstalled, put dish soap, and hand sanitizer, pumped, saw no bubbles. I am at the end of my rope... I broke the cardinal sin... I fixed what wasn't broken, and now it's broken! I just wanna ride. :(
 

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Super Moderator
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11,959 Posts
Not sure if this even is part of your problem, and no proof so far if its even true.....
But I have long suspected the reason many have problems bleeding the brakes on the Vulcan is partly due to the "junction" where the two lines from the wheel meet up. I belive air can get trapped in there and become difficult to wash out. If the bikes on the sidestand and you keep turning the wheel to bleed both sides it would seem the air rises up in the junction and gets trapped...up by the side you're not working on.
My suggestion it to make sure the bike is level on the centerstand and the wheel stays pointed straight ahead.

Back when I worked in a shop, we used to tap on the brake lines with the handle of a screwdriver to coax air bubbles to ride up the hose. We always reverse bled the brakes by pumping fluid up....

FWIW
 

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Just a regular guy
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833 Posts
Thanks Km... it has been on the center stand the whole time.

What baffles me is the absolute lack of pressure, the calipers don't move at all! I could deal with spongy brakes... it would just need tweaking.. but with no pressure.. I am beginning to think I have a leak somewhere... the thread of the valves being most likely. Unfortunately I have been up since 9 pm last night working and my brain is starting to shut down... the Beam isn't helping.
 

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Dr. Vulcanstein
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1,536 Posts
The "junction" knife is referring to is the same as the "yoke" I referred to in the previous post. If you are clamping the hose below the MC and getting pressure, but none at the caliper you have a leak in there. That yoke while regardless of trapping a little air will still let the fluid bleed down, it would just be squishy till the bubbles bled out.


I didn't realise I had a leak in mine until I got pissed and pumped the shyte out of my lever rapidly, and that's when I heard a sucking sound. Still I'm not saying that's your case but I really don't know what else it could be.

You didn't by reverse gravity fluid did you. It's meant for back bleeding and is formulated to rise up going against the laws of gravity. If you try to use it following regular gravity feed procedure it will rise back up once the brake lever is released.....I'm an A-hole:doh:

Worse comes to worse if you have to buy a new caliper, if you can't find one here I bought one on fleabay for $20 and havnt had a problem since.
 

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Just a regular guy
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833 Posts
Yeah.. I kinda figured that. I just bought speed bleeders off Ebay.. I figure at worst.. if I stripped the valve threads this will fix it. Only cost $19 counting shipping.
 

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Super Moderator
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2,570 Posts
I am guessing the junction is probably the biggest cause of our bleeding issues.

when I did mine, and got at least a little bit of brakes, I cracked open the lines exiting the junction one at a time and forced fluid out there.

one thing to remember, there isnt much fluid at all moving in our systems, and it takes a very little air bubble to cause problems
 
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