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Discussion Starter #1
I installed a new front brake line yesterday and spent hours getting pressure built up into it. I think it needs a little more as it's not quite what I had in my OEM line. However this is a Galfer brake line so it may not behave exactly like my stock line.

Anyway I think I read somewhere that the top of the master cylinder reservoir has to be open while you do the pump-lever-open-bleed-screw process in order to prevent a vacuum. Am I getting that right?
 

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Yes, the master cylinder cover should be loose and never allowed to run dry. Bleed the master cylinder first, then the left brake, then the right if you have two front brakes. You shouldn't have to fill the master cylinder more than twice per bleed port even if a new brake line is involved.

If you use a hand vacuum pump instead of pumping the brake you can usually get better results, especially if you have a lot of air like when replacing a brake line. You can get a cheap one for $25 or less and may even be able to borrow one from a local auto parts store that has loaner tools.
 

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Discussion Starter #4
Guys, thanks. Let me start by saying I'm a complete n00b at this. I've never done brake work of any kind before so I am probably missing something obvious.

Here's what I've done:
1. Filled Master cylinder after replacing brake lines.
2. Loosened the bleeder screw on right brake caliper and used a Mighty Vac pump to pull fluid down.
3. Repeated step 2 for the left brake caliper.
4. To build pressure I started by treating the MC banjo bolt like it was a bleeder valve. I pumped the brake lever several times, held it down, loosened the banjo bolt, tightened the banjo bolt, and released the brake lever. I repeated this several times to build pressure.
5. I went to the right caliper bleed screw and pumped the brake lever several times, held it down, loosened the bleed screw, tightened the bleed screw, and released the brake lever.
6. I repeated step 5 for the left caliper.

I was finally able to build pressure using these methods. But something still worries me. No matter how I tried I kept getting air bubbles through the mighty vac hose when I tried to use it to remove the air from the caliper bleed screws. I don't know if I had the screw too loose or too tight but I was not able to remove the air this way.

I went for a test ride and my pressure seems about 95% of what it should be. But I hear these little "barks" and "squelches" when I apply heavy front brake pressure sometimes.

Are my brakes going to fail and will I die in a fire?
 

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Bleed it once more but do it manually without the pump. Use the hose and the container from the pump kit to catch it. Most likely those tine bubbles are from the pump sucking air in from around the bleed screw. That's the only thing I hate about using them. Also bleed the left caliper first then the right. When bleeding brakes always start at your furthers point from the MC and work your way back. So bleed left then right.
 

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Guys, thanks. Let me start by saying I'm a complete n00b at this. I've never done brake work of any kind before so I am probably missing something obvious.
We All Start Somewhere.. ;)

4. To build pressure I started by treating the MC banjo bolt like it was a bleeder valve. I pumped the brake lever several times, held it down, loosened the banjo bolt, tightened the banjo bolt, and released the brake lever. I repeated this several times to build pressure.
I could be wrong, but if you're using the banjo bolt by the MC (on the handlebars right?) then you're most likely not going to get any air out of the lines past that, but again, I could be wrong. When I bleed brakes, I always bleed from the caliper. Loosen the MC cap. Connect your bleeder line to the bleeder valve and crack it loose, then pump the brakes a few times and hold it then tighten the valve and release. (You'll probably need two people for this. Repeat this procedure until you don't see anymore bubbles. And, as others have mentioned, make sure you don't run the MC dry.. It's also, at least with cars, best to start with the caliper farthest from the cylinder. So do the left side then the right side.. If I'm off base with any of this, please let me know. Hope this helps!

Good Luck :)

eGo
 

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Discussion Starter #8
Bleed it once more but do it manually without the pump. Use the hose and the container from the pump kit to catch it. Most likely those tine bubbles are from the pump sucking air in from around the bleed screw. That's the only thing I hate about using them. Also bleed the left caliper first then the right. When bleeding brakes always start at your furthers point from the MC and work your way back. So bleed left then right.
Summer, this is why I have trouble. The videos I've watch say start with the MC. But I guess it doesn't matter as long as it works.
 

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Discussion Starter #9
Do you guys think it makes a difference whether the bike is straight up or on the kickstand? I keep having the most trouble with the left caliper. I think I actually got the right one bled completely free of air.
 

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I've always done MC first. Then brakes starting from the farthest from the MC. Unless the MC was drained many people skip this step. I don't like skipping it, but that's me. I hate mushy brakes.
 

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Discussion Starter #11
I've always done MC first. Then brakes starting from the farthest from the MC. Unless the MC was drained many people skip this step. I don't like skipping it, but that's me. I hate mushy brakes.
Only way I could adjust the MC was with the banjo bolt. Is that what you mean?
 

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You can do it that way but it's still better from the brake bleeder. Pumping the brakes will clear air from the MC better than a vacuum pump, IMO. But, the vacuum pump is better for the calipers. Always protect from leaks of any kind and you should be good. Bleeders can leak and a careful wrap of teflon usually does the trick. They only need to be cracked open an 1/8 to 1/4 turn. There's no good way to protect from leaking if you crack the banjo bolt open except to keep it under constant pressure and leaking.
 

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Discussion Starter #13
You can do it that way but it's still better from the brake bleeder. Pumping the brakes will clear air from the MC better than a vacuum pump, IMO. But, the vacuum pump is better for the calipers. Always protect from leaks of any kind and you should be good. Bleeders can leak and a careful wrap of teflon usually does the trick. They only need to be cracked open an 1/8 to 1/4 turn. There's no good way to protect from leaking if you crack the banjo bolt open except to keep it under constant pressure and leaking.
There's no bleeder on my MC so I'm not sure what you mean unless you mean just pumping the lever until bubbles stop coming to the top of the fluid in the reservoir.
 

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Discussion Starter #14
Guys, I think I got it. Thanks for the help. Summer, you were right. The pump just wasn't making a good seal on that bleeder bolt. When I used just the tube and a wrench I could see all the air was gone from both calipers and I was able to put a good amount of pressure on the brake. Next time I will be able to do this a lot better.
 

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Just looked through my service manual on this. It mentions nothing about bleeding the MC. Even when replaced. Just bleed from the calipers and you will be fine. In regard to your question about the bike being level the only thing mentioned in the book about that is "turn the handlebars so the master cylinder is level"
I did however just notice this...

"The settings on the front brake lever adjuster affects bleeding. Initially bleed the front brakes with the adjuster turned to the softest setting. Once the brakes feel solid, check the feel with the adjuster in several different settings. If the lever feels soft at any settings or if the lever hits the handlebars, air is still trapped in the system. Continue bleeding the system"

It also suggests lightly tapping the MC and calipers with a rubber mallet to release any trapped air bubbles.

Just realized you posted while I was typing this. Glad to see you got it figured out. Now go enjoy your long weekend. :D
 

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Discussion Starter #16
Hey, that's great info to have. I'd say my pressure is probably 95% what it was before I started. If I try hard I can get the lever back but it's pretty solid. I'll have to dig this up next time I need to do my brakes.

I can't enjoy the ride yet however, because now I need a new clutch and throttle cables haha!

Also, can you recommend me a good place to get a service manual? You can PM if we're getting too off topic for this thread.
 

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Mine was in the saddlebag when I bought the bike. :D Guess I got lucky. I would suggest an online search or check the for sale section here as well.

If you are unaware of it, this site has a wealth of knowledge as well...https://sites.google.com/site/vstar1100kb/home

That's is assuming you have an 1100.
 

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There's no bleeder on my MC so I'm not sure what you mean unless you mean just pumping the lever until bubbles stop coming to the top of the fluid in the reservoir.
I was sure I wrote that not all MCs have bleeders. Doesn't matter. Glad you got it.
 

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Discussion Starter #20
Well I'm resurrecting this thread because I've been riding once or twice and I'm not happy with the brake pressure. I just want to check with you guys that I am doing this right:

1. Pump brake lever several times and hold
2. loosen bleeder valve on caliper
3. Continue squeezing brake lever until it hits handlebar and then tighten caliper bleeder valve

Those are the steps I did. I did about 8 times on each caliper but I still think my brakes aren't what they should be. I have a new bottle of brake fluid like what I used a couple weeks ago. I wasn't sure if it was ok to start this process again. I've heard mixing old brake fluid with new brake fluid is a no-no but I have no idea what is considered old.

Thanks again
 
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