Air in your brake lines - Don't Bleed 'em! [Archive] - Suzuki SV650 Forum: SV650, SV1000, Gladius Forums

: Air in your brake lines - Don't Bleed 'em!


Currently
10-30-2006, 03:47 PM
Picked this up from another board and it deserves mentioning here.*

Disclaimer: When you compress your pistons, make sure that there is
enough room in your reservoir to accept the incoming brake fluid.
Brake fluid loves to eat paint up, you don't want that reservoir overflowing.
+++++++++++++++++++++++++++++++++++++++++++++++++

You heard me!

I've tried a zillion different ways to try to bleed my brake lines to get that nice rock solid feel at the brake lever. None of them worked to my complete satisfaction.

Here is my trick that I've been doing:


-Take the cover off of your brake fluid reservoir.

-Take off your right side (throttle side) caliper and press all the pistons all the way in. You will send any air bubble right up the line to the reservoir.

-Put the right side caliper back, you don't need to torque the mounting bolts to 28 lbs-ft yet as you are going to take it off once more. Just tighten it mildly to get in place.

-Now squeeze the brake lever a few times to take up the caliper travel so the pads are in contact the rotors. You are filling the line with pure brake fluid with no chance for air to get back in.

-Now undo the left side caliper (clutch lever side) and do the same. Press all the pistons in and it will send any bubbles across the line and into the left side caliper (and most likely beyond it up towards the reservoir).

-place a piece of wood (plywood maybe?)in the left side caliper so the pistons can't come back out for the moment.

-Don't remount the left caliper yet.

-Now take off the right side caliper again and press in all the pistons again.

-Now remount both calipers... be a good boy/girl.... use a torque wrench at 28 lbs-ft.

-squeeze the lever a number of times to refill both calipers with bubble free brake fluid.






If you don't see air bubbles come out of your system at the reservoir, you can call me a monkey!

Your brake lever will feel as solid as anything. It gives an absolute feel of control for your brakes.

No mess, no spilling brake fluid. It takes about 15 minutes to do.

Now go do it!

If you have a two line system in parallel, it works even better.

My TLR calipers are hooked in series so I have to do this whole process.

Double check your torque spec for your bike's calipers... I just said 28 lbs-ft cause that is what mine is.

MagpieTear
10-30-2006, 05:17 PM
I dunno, sounds too easy... where's the swearing, the dropped wrenches, the DOT4 peeling paint from your tank and contaminating the enviroment, causing my next child to have fins? Not even enough time to drink a beer.

I'll have to give it a shot. Still more fun to get a friend over to show me how to do it the old fashioned way and have him to shoo me away before I hurt myself. :BangHead: Next time I'll have him come over after 11:00. :occasion14: (8:00 am was too early for beer)

sicksv650
12-03-2006, 12:30 AM
i still think the air vacuum bleeder hooked up for about 30 second on each bleeder is quickest, easiest, and cleanest.

Ranger
12-03-2006, 01:14 AM
I'm up for anything that will make the process easier. Thank goodness i don't have to do it again until next year.

jwalstad
12-10-2006, 01:16 PM
i still think the air vacuum bleeder hooked up for about 30 second on each bleeder is quickest, easiest, and cleanest.


+1

Why not just get a vacuum pump bleeder. It's only like $20 and stops a lot of heartache and frustration.

Jesse H
12-20-2006, 11:48 PM
Also, I don't mind actually bleeding them so that the old fluid is replaced with fresh fluid. With speedbleeders, it's cake.

Hank is Here
12-21-2006, 10:17 PM
I just gravity bleed my front brake system and just dropped the fluid on the front rim. If you were worried about peeling paint then just get about 2 ft of clear PVC tubing on each bleeder to take it away from all painted surfaces

schleppy
03-13-2007, 07:52 PM
Has anyone tested this method out yet? It sounds perfectly reasonable to me, and relatively easy. I'm tempted to try it tomorrow...

NHSVnaked
03-13-2007, 07:59 PM
I have never used those brake vacs or any tricks and Mine are SOLID. I had to bleed mine when I put my goodridges SS lines on

infinotize
03-13-2007, 08:37 PM
How solid does everyones lever feel? Mine seems a bit soft, but I've only had my SV for a few weeks and have no comparison. I like my lever distance on the "5" setting, and at a standstill I can allllllmost pull the lever to the bar. I think if I pulled it that hard moving I'd be locking the front or doing a stoppie, but it still feels like it should have less play/softness.

The bike is a K4 and I doubt the fluid has been changed so I was figuring on doing a gravity bleed, does that also clear all the air out of the line?

Currently
03-13-2007, 08:44 PM
Yes .. as long as you don't let the reservoir drain dry.
Once you do let it drain dry ... you now have a nice job ahead of you.

imdying
04-10-2007, 10:43 PM
Press all the pistons in and it will send any bubbles across the line and into the left side caliper (and most likely beyond it up towards the reservoir).Along with any **** in the lines. Brakes shops will never do this (they hose clamp the lines and push out the bleeder) because now and then you'll fit brake pads, and toast the customers master cylinder.... and they love that.

Currently
04-10-2007, 10:53 PM
You would never believe where I picked that up ... ;D

imdying
04-10-2007, 11:03 PM
Best not be going back to that brake shop :rofl:

doxiedog
04-11-2007, 01:20 AM
I just gravity bleed mine :thumbsup:

Northwind
05-02-2007, 02:23 PM
That simple method's about 10 times more complicated than using a pressure or vaccum bleeder. And don't think that means $$$, my "pressure bleeder" is a big syringe with a bit of tube attached. Fill with fluid, squirt through from each nipple in turn- works exactly the same way as this method really, just that it uses an external source of pressure rather than the pistons. I hate bleeding brakes with a passion, so it's kind of nice to be able to do a complete fluid swap in under 5 minutes.

Nudist
05-16-2007, 02:35 PM
I'm bleeding brakes tonight.... I will try it and let you all know if it works.

DougZ
05-16-2007, 02:37 PM
Where to get these syringes? I always have trouble with bleeding my rear brakes....something funny with the two nipple set ups. My fronts, I have never had trouble with. :dontknow:

Northwind
05-16-2007, 02:42 PM
thanks Northy! :occasion14:


Thank the guy who told me :) It's an old trick, but I think a lot of people consider it a bit ghetto. DougZ, hate to admit it but I bought mine off Ebay for about 10 times what it cost the seller :tard: Just couldn't be bothered to go and find one cheap, for such a small saving.

DougZ
05-16-2007, 02:56 PM
No...but I'll search around....I wouldn't know if there was.

Currently
05-21-2007, 05:45 PM
Doug ... I will bring you one to the Rally ... stop looking.

incubus
06-10-2007, 09:04 PM
There's only one problem with this...


Water LOVES brake fluid!!


If you leave your res. open any longer than you have to, you'll be gettin water (humidity) in the brake fluid making it squishy.

imdying
06-10-2007, 10:01 PM
There's only one problem with this...


Water LOVES brake fluid!!


If you leave your res. open any longer than you have to, you'll be gettin water (humidity) in the brake fluid making it squishy.
It doesn't love it that much... there are papers written on the hygroscopic nature of brake fluid, the rate at which it absorbs moisture isn't as bad as you'd think. Still shouldn't leave it open though, but yeah.

jsterlingt
07-08-2007, 02:46 PM
I may have missed it, but no one mentioned the fact that in a complete fluid exchange you should also bleed your master cylinder first, then I use a vac bleeder. everyone may think the vac bleeder will get the master cylinder all the way, but i just don't trust it.

Northwind
07-09-2007, 10:20 AM
I may have missed it, but no one mentioned the fact that in a complete fluid exchange you should also bleed your master cylinder first, then I use a vac bleeder. everyone may think the vac bleeder will get the master cylinder all the way, but i just don't trust it.


Yep, though a lot of newer m/cs have a top bleeder which makes that pretty much irrelevant, lovely simple design improvement that. I keep forgetting that not everybody has it, since it's so natural to use. If you're pushing fluid through the system from the bottom end then bleeding the m/c won't usually be neccesary though.

ari211
08-25-2007, 01:47 AM
So I read the entire post and like the idea of forcing pure fluid up from the nipples, aiding any trapped air bubbles in their desire to rise up. The method involving removing the calipers seemed like a pain in the ass, I liked the idea of using a syringe. I bought mine at the local vet's office for $3. They called it a "cathider-tipped feeding syringe, 60 CC's". Slap on a few inches of 1/4 tubing and I was done in 10 minutes with excellent lever feel. Very satisfied!
So what I'm saying is you can get the syringe at a vet's office.

Jacob
10-24-2007, 10:50 AM
I have never used those brake vacs or any tricks and Mine are SOLID. I had to bleed mine when I put my goodridges SS lines on

+1 Except I used Galfer SS lines ;)

imdying
10-25-2007, 09:07 PM
Yep, though a lot of newer m/cs have a top bleeder which makes that pretty much irrelevant, lovely simple design improvement that. I keep forgetting that not everybody has it, since it's so natural to use. If you're pushing fluid through the system from the bottom end then bleeding the m/c won't usually be neccesary though.LHP have banjo bolts with built in bleeders that you can use to retrofit this capability to older bikes :) I'm of the opinion that this is a worthwhile mod for anyone who is likely to change lines or calipers... won't make a difference to your annual fluid change, but any time you have a dry system, it'll speed the job up by 5 minutes (and keep you and your baby cleaner).

ziptech800
11-13-2007, 03:13 PM
+1 -- this is called the "poor man's bleed"... and it works. Make SURE your pistons are flossed and nick-free before compressing them back past the seals. ;)

Bleeding at the caliper only gets rid of air trapped in the caliper body. If say you're filling a system for the first time, lots of air has to get displaced to accept the new fluid -- and not all of that air gets out. Much of it gets trapped in the hidey holes in the non-smooth transitions at banjo and junctions. I really dislike the crossover systems that Suzuki is fond of using, since air likes to get trapped in the crossover -- and air doesn't care where it is, if it's present, you'll get wasted lever motion. Their lines flex a good deal too, and if you don't know what good feel is, you won't know it's the mushy, inconsistent feel it is -- bled improperly.

Forcing back the pistons pushes the air from those high places -- but you have to displace enough to get the air into the reservoir, or you're just moving it around.

I can see the advantage to vacuum bleeders... I used to do it with a Vacula. But without a compressor, the poor man's bleed is a good alternative.

Another way to rock up the lever, is to tie a ziptie around the bar and lever, just enough to have feel, and leave overnight. This usually works best with good bleeds but for that tiny bit extra, by forcing water vapor out of the seals. Not too hard, though... and it's not going to work well unless the majority of air is already out. ;)