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Brake Question

Posted: 08:35 am May 07 2006
by Green Hornet
I mounted the KX Front Caliper along with Braided SS Brake Line. The problem is, how the F$%K do you get the fricking air out of these lines. It bubbles, bubbles & bubbles with very little leaving the master cyliner. I pumppppp, then bleedddddd. Am I missing something :rolleyes:
The brake caliber & Brake Line have been drained completely. Am I supposed to prime the caliber, the lines?? Any Ideas??

Posted: 02:27 pm May 07 2006
by IdahoCharley
1. Get yourself a 20-30 cc syringe and some small clear tygon tubing. (6 inches is enough) I buy them at army surplus store but they are sold in drug stores and cooking stores. These syringes are the plastic nozzle variety verses the needle variety.

2. Remove the cover from the master cylinder and open the bleed screw on the caliper.

3. Fill the syringe with brake fluid attach the small tubing between the syringe and bleed screw on the caliper ensuring first that all air is out of the syringe.

4. Slowly apply a steady pressure to the syringe forcing brake fluid into the caliper, up the line, and into the master cylinder. Trapped air will be push up with the fluid.

5. Once the master cylinder is full work the brake lever slowly a few times. The syringe should extend and retract and you may get a few bubbles out of each end - back into the syringe (keep the syringe high so any bubble out of the caliper rise into the syringe - i.e. the hose remains full) and maybe a few up and out of the master cylinder.

6. Close bleed screw and remove tubing.

7. Adjust fluid level in master cylinder and reinstall cleaned black neoprene seal and cap.

NOTE - If one syringe load of brake fluid is not enough you can repeat the procedure just be sure to ensure all the air is out of the syringe and attached tygon line when you reopen the line. (It is actually ok to have air at the plunger surface, within the syringe, as long as you keep the syringe oriented correctly (fluid output end down) and do not push the trapped air into the tygon tubing)

FWIW - Backbleeding is simple and fast and after the first time only takes a couple of minutes to perform. Purchasing tubing that fits tight on the syringe and caliper bleed fitting makes this task very simple. You will need both hands and I stress a Slow Steady Pressure on the Syringe is all that is needed. If your tubing is a loose fit on either the bleed screw or syringe/ or if you just want to shoot the fluid into the brake caliper - you will likely take a bath in brake fluid or spray it around - NOT a GOOD THING! Charley

Posted: 03:26 pm May 07 2006
by Indawoods
Perfect explaination Charley! :supz:

Posted: 11:49 pm May 07 2006
by skipro3
When I was bleeding my f#@% brakes, I too, had tons of air bubbles. I thought that is was from air in my lines but it wasn't. I was sucking air past my bleeder hose line. Since then, I bought a speed bleeder. Now I can bleed that thing in less than 5 minutes. Check them out at http://www.speedbleeder.com

I also have the speedbleeders on my streetbike clutch as well as front and rear brakes. They make a nasty job almost fun.

Posted: 11:12 am May 08 2006
by Green Hornet
I just ordered those and made my own VACUUM. I sucked on the hose. I now have brakes. WOOOO HOOOO

Posted: 05:24 pm May 08 2006
by KanuckKDX
Thanks for the information. I just bled front and back and there is no way I expected to get air in the lines. But now I know how to solve the problem.

The speedbleeder looks great but I am going to try the syringe solution since it will work on all the bikes and maybe the truck too.

But I will have to find out what tygon tubing is and find some.

Posted: 05:45 pm May 08 2006
by canyncarvr
Question: Is that schedule 20 tygon or schedule 40 tygon? After all...it is PVC!



Honestly...doesn't everybody know that:

TYGON® LFL Tubing
Advantages:


Longest life of all TYGON peristaltic tubings (1000 hrs).
Nonaging, nonoxidizing.
Clear for easy flow monitoring.
Broad chemical resistance.
Low gas permeability. (Your gas won't fall out of it)
Smooth bore.
Good for viscous fluids.
High dielectric constant. (This is mission critical!!)

Limitations:


Potential leaching of plasticizer.

Application Suitability:
Acids: Good
Alkalies: Good
Organic solvents: Not recommended (Obviously GREAT for gasoline!! Right??)
Pressure: Good
Vacuum: Good
Viscous fluids: Excellent
Sterile fluids: Good


Physical Characteristics and Compostion:


Thermoplastic.
PVC-based material with plasticizer.
Firm (stiff) material.
Transparent, clear.

Temperature Range:
-58 to 165°F (-50 to 74°C)

Meets Classifications:


USP Class VI
FDA 21 CFR 175.300

Gas Permeability:
cc x mm x 10-10

(cm2 x sec. x cm Hg

CO2: 563 (Thank the Lord for THAT!!)
H2: -
O2: 124
N2: 67


Cleaning/Sterilization:


Sterilize with ethylene oxide (ETO) or autoclave.
To autoclave: Coil loosely in nonlinting cloth or paper; autoclave at 250°F (121°C), 15 psi for 30 minutes (tubing will appear milky); air dry at max 150°F (66°C) for 2 to 2.5 hours until clear.

Capiche?

Posted: 06:09 pm May 08 2006
by canyncarvr
re: 'When I was bleeding my forks, I too, had tons of air bubbles..'

And the speed bleeders fixed that? If I've ever had air in my fork lines, I've never even noticed it!

Wow. A TON of bubbles would be a !LOT! of bubbles. I tried weighing some bubbles once. Had NO luck whatsover. :roll:

Posted: 08:35 pm May 08 2006
by Colorado Mike
<Mike starts to a semi-awake state> Harruugh?? Bleed my forks? with Tygon Jihn Jedi mind-trick plastic toobes? WTF? My forks have the dumb old steel tubes. The ones that stay pretty stiff when they go up and down. Like a dumb ass, I bought new forks, and wooden ewe know, They're steel too!!

:roll:

</semi-awake state>

Posted: 12:04 pm May 09 2006
by canyncarvr
OOOhhhhh...the monkey's gettin' a pokin'!! ...and that's not a good thing! :blink:

Posted: 03:25 pm May 09 2006
by skipro3
It's been corrected. I will apply correction to you too, once you get here next weekend. Read up on the ride thread for more details later today, to preview your punishment.

Posted: 03:44 pm May 09 2006
by Colorado Mike
Wow. Looks like the monkey has a potty mouth when he gets annoyed. I gotta get back to checking my forks for blood.

Posted: 06:34 pm May 09 2006
by IdahoCharley
I'am glad I came back to this thread - never heard of the speed bleeders on the bleed valve. Seems like a good idea but could be expensive if you put them on everything.

When refilling a system that has been broken open I have not found anything quicker or more sure than using a backbleed method.

Posted: 02:54 pm Jun 11 2006
by Indawoods
Well.... had some issue with bleeding the brakes on my brothers bike with KX frontend today.

Both bleeders front and back were blocked and was just getting air.

I found that a piece of mig welding wire and brake cleaner resolved that issue well by spraying, digging out the crud and spraying, repeat, repeat.

No issue after that .... bled real easy with the Mity-Vac tool.

So, the problem with bleeding the brake lines could be as simple as cleaning out your bleeders real well. Worked for me anyway.... :grin:

Posted: 01:08 pm Jun 12 2006
by canyncarvr
Well, you know it now..but that is pretty common.

Before any bleeding ops and ESPECIALLY BEFORE ANY PRESSURE BLEEDING METHOD!!, DO make sure the bleeder isn't full of junk. Obviously pushing the crud into the system (pressure method) won't be a good thing...especially when it gets up to the MC.

This has been mentioned somewheres before I'm sure..but wrapping the bleeders with teflon tape is usually a good idea. Otherwise you can easily get air introduced into the setup.

Yes, a MiteyVac works good..and IS more expensive than a syringe. Something neat about the Vac method is the pressure stays constant during the process. The added fluid in the Vac reservoir replaces the air 'removed', so the pressure stays the same. IF the pressure drops, you're leaking somewhere!

Posted: 09:12 am Jul 11 2006
by wanaride
I want to try out this syringe method for my first brake fluid change. Can anyone tell me what diameter tubing will fit on the bleed valve? I presume this will automatically fit on a typical syringe?

I'm sorry but I need details!

Any other tips for someone who hasn't changed brake fluid before???

Thanks for your help! :supz:

Posted: 12:44 pm Jul 11 2006
by canyncarvr
Sorry, I don't have a number. As IC has noted before, get a syringe that is NOT for hypodermics (needles).

Heck...give him a PM if he doesn't chime in here. I use a vacuum pump (MityVac) and the tubing that came with it.

Any car parts place likely has a bleeder valve around..and would either know the tubing to use or you could check the fit yourself. As noted, clear tubing is desireable..so you can see what's going on (dirt, bubbles etc.)

Tips? Brake fluid is nasty. Keep it OFF 'stuff'. Painted stuff, plastic stuff. A touch of it puts my brother-in-law in the ER. Be careful with it.

Sealed container and all that stuff. If your fluid has been sitting around for years, probably get some new stuff. DOT 3 mixes with DOT 4 OK. If you ever mess with a DOT 5 system, keep in mind that is completely different and any mixing will destroy the system.

I didn't read back thru all of this thread...some of that may be repeated.

That's helpful, 'eh? :cry:

Posted: 12:55 pm Jul 11 2006
by KDXer
I now have speed bleeders also but I used to just put a hose off the bleeder in a jar, open the bleeder, let gravity drain the fluid as I continue to top the M/C. After a few hundred MLS I close the bleeder and pour the fluid back into the bottle for next time. Job done.

Posted: 05:09 pm Jul 11 2006
by Indawoods
I was at Cub Foods the other day and they had a broth injector hanging in the isle that would be perfect. Don't know if it was chemically resistant at all but for the $4 they wanted for it... I proly wouldn't care if I didn't have my Mighty-Vac.

Posted: 06:54 pm Jul 11 2006
by canyncarvr
Broth injector...:hmm:

Mr. Moderator..might your post have been intended for the HGH thread?