Front brake won't bleed

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CustomMax

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My daughter bought me brake pads for my bike. I've been riding without front brakes since I had a leak from my reservoir so I had Sean rebuild it when I sent it to him cause the screw hole was stripped. So I put the pads on and put fluid in and I'm trying to bleed it and it just WON'T pump up! I pump the lever but it just has no pressure. I tried open the bleeder and when I pump the lever a small amount of fluid comes out. So I tighten the bleeder and no matter how many times I pump it, nothing! Any suggestions before I take the fucking front brakes off completely!! I fucked with this thing a good part of the day yesterday and I'm REALLY ready to shit can the front brakes all together and I know that's not a good idea but I can't afford to put money into them till I get my other debts paid off.
 
You cant pump the cylinder with the bleed valve open. It lets air back in.
You have to pump the brake lever with the bleeder closed. Then while holding the lever squeezed, you open the bleeder screw and then close it again. Then pump the lever again, hold, then open the bleeder and close it, then release the brake lever, repeat until no air comes out the bleeder.
I do it pumping the brake lever several times, then hold, open the bleeder, close the bleeder, then release the brake lever, then repeat.
It's a major pain because you are forcing air down when it naturally travels up. But keep at it and you will get it.
I always take a clear piece of vacuum tubing and put it over the bleeder as to not get brake fluid all over the brakes and rims. Cut a piece long enough so you can go up then down into a pan or bottle that way fluid and air will rise up into the tube from the bleeder and you can prevent air from getting back into the bleeder by keeping fluid in the tube just above the bleeder.
Another option is to buy or borrow a mytivac. It helps a lot.
Above all make sure you keep adding fluid to the reservoir as to not allow air to get back in the piston during the process.
I just put new Galfer lines on my clutch, front and rear brakes. My mytivac shit the bed. So I know your frustration.
It's a lot of pumping.
 
Thanks Robert, I knew better than to listen to the idiot that told me to pump it with the bleeder open but at that point I was so frustrated I was willing to try anything. But I'll keep at it and hopefully I get this resolved cause I don't know if anyone here ever tried to ride a Vmax w/no front brakes especially with all the hills here in Pa but its a major pain in the ass. Probably not the safest thing I've ever done either. Ok, I'll give it another go. Ed
 
Also be very careful pumping the lever rapidly with the cover off the reservoir. When it starts to prime up a stream of fluid will squirt back up while your pumping the lever and possibly get all over everything. So go easy when the cover is off the reservoir.
 
I cover everything on the bike with thick towels when doing anything with brake fluid!!! Have ruined more than one painted item on a bike in my life.... :bang head:
 
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On a dry system you may have to leave the bleeder open till the piston gets primed so the air has some place to go while the piston gets fluid into it. But once the piston gets fluid into it. you have to close the bleeder to build up pressure. Pressure is what pushes the air out when you open the bleeder. And the piston has a small volume. So it takes a while to get it done. But it will eventually get there.
 
I cover everything on the bike with thick towels when doing anything with brake fluid!!! Have ruined more than painted item on a bike in my life.... :bang head:

Yea, had that issue before and wound up repainting the bike but I wanted to anyway. But $1200.00 later I'm gonna be super careful not to get any brake fluid anywhere on any chrome or paint. So, thanks for the reminder. Ed
 
Ed another faster way is to push it back to the master from the calliper using a meat tenderizer needle just push slow so you dont push it all over n out of master.
 
On a dry system you may have to leave the bleeder open till the piston gets primed so the air has some place to go while the piston gets fluid into it. But once the piston gets fluid into it. you have to close the bleeder to build up pressure. Pressure is what pushes the air out when you open the bleeder. And the piston has a small volume. So it takes a while to get it done. But it will eventually get there.

Robert, are you saying to just open the bleeder and let it sit until fluid fills the caliper by gravity otherwise pumping it with it open will suck air into it or should I tie the brake lever back to allow it to flow down from the res? I thought of doing that but didn't know if that would help. Thanks
 
There's a little weep hole in the res itself (hence the fountain of fluid people mention). If after doing it with the bleeder closed for awhile (should take like 30 minutes manually) you may want to rest it for a bit and let the air settle.

While letting it rest - it's not a bad idea to just tie or rubberband the lever to the bar, so any air that does float to the top is free to bubble up out of the res.

Do make a point of closing up the res if you leave it sit like this though. Brake fluid is a magnet for water, and water ruins brake fluid.
 
Robert, are you saying to just open the bleeder and let it sit until fluid fills the caliper by gravity otherwise pumping it with it open will suck air into it or should I tie the brake lever back to allow it to flow down from the res? I thought of doing that but didn't know if that would help. Thanks

No, I've always just pumped it with the bleeder closed.
You can try gravity feed.
But what I was saying is in the very beginning if the master has no fluid in it at all, leave the bleeder open just for the first few pumps till the piston fills with fluid.
You have already been pumping it so the piston will have fluid in it by now. So don't pump it with the bleeder open.
 
And this is just my opinion, but tying the bake lever squeezed is not going to allow air or fluid to come back up.
When you do that it pushes the piston all the way into the chamber and therefore nothing can come back up because the chamber is closed by the piston.
I may be wrong on that. Because I've never seen a schematic on the master cylinder. But the way i picture it in my mind is that when the brake lever is fully squeezed the piston is pushed into the chamber and therefore there is no room for liquid or air to come back into the chamber.
 
I haven't read all of this but if im repeating something just bare with me... One thing to have on hand, a wet towel inside a bucket with water (its the only thing that dilutes glicol based brake fluid - DOT3,4 and 5.1) If it drips onto the polish or paint work immediately rinse it with water. For you to bleed properly instead of using vacuum hose use a clear one so you can see the fluid exiting (you see the air bubbles moving out) if you release the lever the fluid will get back in again with or without air and the clear hose allows you to see it reverse direction...
 
Another note on bleeding brakes from a dry condition. I have much better luck first bleeding the master by itself in order to get it started. I do that by leaving the banjo bolt from the brake line OFF. I use the tip of my finger to open & close the outlet hole on the master until I've established pressure in the master cylinder. Then I re-attach the brake line and bleed all the way to the wheel cylinders.
 
I'll pay your life insurance policy, just let me name myself as beneficiary if you wanna remove your VMax front brakes.

I don't mean to be rude, but if you don't know how to bleed brakes properly, you should not be working on yours!

At the very least, get someone to show you how to do it correctly and safely, read all you want on here and the internet, but get someone who knows what they are doing to give you a hands-on tutorial. Brakes are probably the most-important system on a vehicle, two, three, four, or more wheels. Unicycles don't need them. And, no, I am not referring to those oddball powered ones made by that guy in MI who has done them since the 1970's.

Your local vo-tech school probably has a motorcycle mechanics class you should take. Stumbling-along trying to do it correctly but without the essential basic knowlege is like juggling a pair of loaded hair-trigger automatics in a crowd-someone's gonna get hurt.

We all have to start somewhere, but common sense should always prevail around mechanical things, whether it's chainsaws, motorcycle brakes, firearms, boats, or aircraft, to name a few.
 
When I am unfamilar with something, I always go on Youtube and find the info on there. Usually someone has had the same problem and made a video on the subject in question.........
 
Who the fuck said I was "unfamiliar" with working on brakes! I've bled my brakes hundreds of times but never had issues like this bike before, that's all. Believe me I've had this fucking thing torn down alot farther than most people ever have had to. So, thanks,
 
Glad you got it all squared away. I'm still procrastinating on putting my new galfer front brake lines on because I know its going to be a lot of pumping.
 
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