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sierra308
13th April 2006, 06:59
I just put a chrome master cylinder on my 1200C.I pumped the lever about a 1000 times still got no air out of the bleeder.I have plenty of brake, but the lever goes to a little more than 3/4 of the way before the brake starts working.Before the swap I only had to go about 1/4 of the way for the same amount of braking.Can anyone give me any ideas.Thanks,sierra308.

Moved On
13th April 2006, 08:25
It takes approximately 2385 pulls of the brake lever before all the air comes out.

Seriously it takes a long time. Each time I've done mine I get my wife to come out and help me. I always forget whet the secret is, but just about the time she tells me that "this is stupid" and she is "not going to help me anymore", I get the pressure starting to build up and get the swing of the proper sequence of squeeze, cover, open bleeder, close bleeder, squeeze, etc...

I'm sorry I can't remember the magic sequence right now.... but keep working it, you will get it mastered... then you'll forget again just before you take them off next time.

It'll tighten up eventually... you don't want to leave it where it is.

Sometimes letting it sit for a while helps. Try tapping the side of the brake line with the handle of a screwdriver to loosen up the bubbles. Remember that new bottle of brake fluid is way more than you need, so don't worry about wasting some... let it flow out while you squeeze for a while, that'll help carry the air out.

Gazza

TheTick
13th April 2006, 15:32
Go buy a mighty-vac for $30 from any local auto place like autozone or murray's. You'll be done in 5 minutes.

FSZEKE302
13th April 2006, 16:07
This is one of the Black Magic aspects of a HD front brake. I've used the Mighty vac and it helps, but it seems like the best results come when you're so frustrated you give up and go to leave for the night. Just one last squeeze before getting out the 357 and they work. :roflblack Yea, I think Gary's right, seems like 2385 is about right. Worst time I ever had was when I put a new Caliper and SS line on together. Thought it would never bleed, then it did. Best of luck and sorry for the lack of a better answer. :tour

Tucson_Tim
13th April 2006, 16:29
After I rebuilt the front brake master cylinder I bled the front brakes of my 1200R (two calipers - twice the fun) and it took a while. Maybe 20-25 times per caliper. I did it the old-fashioned way, one hand on brake lever, one hand on box-end bleed screw wrench:

- loosen bleed screw
- SLOWLY pump brake to grip
- tighten bleed screw
- SLOWLY release brake
- repeat

I left the cover OFF the master cylinder so I could periodically pour more brake fluid in SLOWLY.

Did it by myself and the brakes are fine. And because of the bleeding it took nearly the entire 12-oz HD DOT-5 bottle.

Tim

H@mbone!
13th April 2006, 16:35
The cheapest route I found doing it your self is going to a grain elevator and getting a 60cc cattle syringe and going and buying some hose that will fit on it and forcing some fluid into the cylinder pull the master cover off and watch it untill you start seeing the level go up on it then you know its got fluid threw the hole system. Then do your regular bleeding pump it a few times release the bleeder and let the air bubbles out tighen it. Keep doing this untill you have no air comeing out top it off and your done. All this takes 10min at the most and is really easy. I just did this a few months ago to mine total cost on tools was around $5. Then brake fluid is about $8-10 bucks at O'Reillys.

ojgp
13th April 2006, 16:44
Sometimes an air bubble gets trapped at the upper banjo bolt...you can check by slightly loosening the bolt, then slowly depressing and holding the lever in while you're retightening the bolt. If there's air there you'll see it...quickly wipe up your mess too if you're not using Dot 5. That said, you can gravity bleed the system too. It takes forever but I've had some stubborn systems respond only to this. Basically, just find something "else" to keep you busy (so you can hang out and keep an eye on the master cylinder) and open the bleed valve, and leave it open and while continuing to top off the master cylinder until you're sure that whatever fluid was first in the master cylinder has finally exited the bleed valve.

GP

'01 1200 C

Uncledaddy
13th April 2006, 21:21
Easy:

1. Make sure all fittings are tight
2. Open the bleed valve and pour brake fluid in the master cylinder until fluid comes out the caliper bleed valve. This is gravity bleeding. Most of the air should be out of the line at this point.
3. Close the bleed valve tight and pump the brake lever. You should have a pretty solid lever.
4. Apply pressure to the lever and crack the bleed valve. Close the bleed valve before the lever bottoms out or you will suck air into the bleed valve.
5. Repeat until there are no more air bubbles coming out of the bleed valve and you have a solid brake lever.

--Make sure you close the caliper bleed valve tight each time with a wrench. Hand tight is not enough.

There is no reason why you should have to pump the brake lever more than a few times if you follow the steps above.

xena
13th April 2006, 21:28
I'm with Uncleaddy. I did mine just as he outlined there, and I
think I had the front brake bled in about ten minutes.
It wasn't anything dramatic like some are saying. I suspect
that whether they know it or not, some people are allowing
air to get in the line and that's why they are having problems.
I had my line off twice in the past couple of years and had
no issues either time.

Stevo uses a method where he "taps" the line. I never had
to try it, and I can't even find the thread that referenced it.

Moved On
13th April 2006, 22:11
I had the front brake bled in about ten minutes.
It wasn't anything dramatic like some are saying.Yea, 10 minutes 2385 pumps... that's approx 4 pumps per second....
you were never a teenaged boy were you Xena??? :D

Gazza

Sraponi
13th April 2006, 22:24
i was bleeding my fronts, i changed all the break fluid. The whole system was empty, so im sitting there for evvveerr bleeding them then i cudnt handle it anymore and dealership hooked up vac to it and did it in a couple of mins

silver ghost
13th April 2006, 23:26
Some have had the same problem and some say they were able to bleed in just a few minutes. The manual says a few pumps but I believe you have to "tickle" the lever. If you pump slowly, you will notice tiny air bubbles in the master cylinder reservior surfacing when you are about halfway through the "pump". Try holding the lever in that halfway position until the bubbles stop surfacing, then slowly pump again. I tried about 1,000 times and then gave up for the night. Went to the trusty forum and read about this problem and then tried the "tickle" method the next day and it was bleed after three pumps. Don't know if it was technique or the fact that I left it over night, but it is worth a try. I think if you pump quickly, you just introduce more air into the line and defeat the purpose. The manual is a little ambiguous about the process. I hope this helps. You'll get it eventually.

bud095
14th April 2006, 00:00
Yea, 10 minutes 2385 pumps... that's approx 4 pumps per second....
you were never a teenaged boy were you Xena??? :D

Gazza
:roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack :roflblack:banana :banana :banana :banana :banana

renegade1
14th April 2006, 04:52
I use a Mighty Vac and it takes a few minutes, you can pick it up at auto parts store for about 25.00.

darth
15th April 2006, 13:29
Easy:

1. Make sure all fittings are tight
2. Open the bleed valve and pour brake fluid in the master cylinder until fluid comes out the caliper bleed valve. This is gravity bleeding. Most of the air should be out of the line at this point.
3. Close the bleed valve tight and pump the brake lever. You should have a pretty solid lever.
4. Apply pressure to the lever and crack the bleed valve. Close the bleed valve before the lever bottoms out or you will suck air into the bleed valve.
5. Repeat until there are no more air bubbles coming out of the bleed valve and you have a solid brake lever.

--Make sure you close the caliper bleed valve tight each time with a wrench. Hand tight is not enough.

There is no reason why you should have to pump the brake lever more than a few times if you follow the steps above.

Uncledaddy has it down... I did this yesterday when I put my new brake line on, took less than 15 minutes and about 10 pumps. I put apes on my bike so there were no "high spots" in the line, so gravity took over! I pumped it about 4 or 5 times to get some fluid in the line, then opened the bleeder. At first you see a little fluid and some air bubbles come out, then when it starts coming out the bleeder clean with no bubbles, you're almost there. At this point, repeat steps 3 - 5 and ya got brakes!
:banana

ntmd8r38
20th April 2006, 00:19
Sometimes an air bubble gets trapped at the upper banjo bolt...you can check by slightly loosening the bolt, then slowly depressing and holding the lever in while you're retightening the bolt. If there's air there you'll see it...quickly wipe up your mess too if you're not using Dot 5. That said, you can gravity bleed the system too. It takes forever but I've had some stubborn systems respond only to this. Basically, just find something "else" to keep you busy (so you can hang out and keep an eye on the master cylinder) and open the bleed valve, and leave it open and while continuing to top off the master cylinder until you're sure that whatever fluid was first in the master cylinder has finally exited the bleed valve.

GP

'01 1200 C

Long time lurker here,,the air in the upper banjo fitting was my problem, thanks! I was going nuts trying to get a firm lever