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Discussion Starter · #1 ·
Brake bleed woes. Trying to bleed my Formula disc brakes. I'm using a squeeze bottle to push fluid from the caliper up to the brake lever port. It's not working. I'm getting no pressure at the lever and no brakes. Am I thinking wrong? Shouldn't reverse bleeding push any air up out the lever port? Do I have to remove the caliper and use a pad block? Can it be done with pads and caliper in place? Is a dual syringe system the only way to bleed them? Sometimes I wish it was just mechanical discs. Trying to get this bike rolling. Do I bite the bullet and spend the $140 to have a shop bleed brakes and replace the rear derailleur cable? That's something I'd hate to do since I prefer doing my own work and that cost seems high. Then again I've been out of the loop for 13 years. Bike labor costs must have risen.

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Elitest thrill junkie
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This question probably hinges on what that valve is at the caliper.

Is this a typical brake caliper valve where you have to loosen it to open it and you can fit a syringe to it? Almost every one of these works the same.

I would not however attempt to bleed it with pads in place, the valve is pointing up, which means you will have to hold a syringe/tubing above it. If that tube pops of and a little fluid gets on the pads, the pads are done. This is why they recommend bleed-blocks, which doesn't need to be anything special, just something the distance of the pads and rotor and a tiny bit more.

What's on the lever? Two-syringe setups typically require a fitting for the lever, where you screw it in. I know some formulas did in fact use this. In almost every situation, you have to use a syringe at the caliper to push fluid up. The two-syringe method just helps to remove bubbles at both ends. Hope is the only one that I know of which is reverse. It's pretty dumb trying to fight gravity, but it also doesn't require syringes, so that's the benefit. Again, what does the reservoir/lever look like? It probably wouldn't hurt to try the Hope technique if it has a big refillable reservoir.
 

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Discussion Starter · #3 ·
Yes. That is the brake bleeder screw on the caliper. Loosen to open/tighten to close.
It is a closed system with no large reservoir.
Port is at the end of the lever where the brake hose connects.

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Elitest thrill junkie
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Elitest thrill junkie
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But you can't even get fluid to come out of the lever when you push it into the caliper. Just checking, you are loosening the caliper bleed nut enough to ensure it's open, with the reservoir fitting open?

If that's not flowing any fluid, then I'm not sure if I'll be much help. There could be a check-valve in there, that would definitely create the results you are experiencing. If that's the case, the only way to do it would be lever down (and I'd recommend taking the caliper off and placing it above the lever, or bleeding with the bike upside down in a stand.

If you can find out what the fitting is, the diameter and thread pitch, you may be able to order it of course. Jagwire makes bleeding adapters for many different brakes and it's likely they may have something. But an even further measure that I had to go to recently (for a fox shock) was to make my own fitting, taking something similar size, and then re-threading it with a die. So if you find out what the threads and size is, even if you can't find the fitting, there is a possibility you might be able to make it. Then you just need a small o-ring to go over it when you tighten to make your seal. I know this sounds dumb, but it works. Otherwise, I would recommend taking the lever fitting out, figure out the threads and size. Take it to a hardware store or shop (like industrial supply shop) that can help with that.
 

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Discussion Starter · #7 ·
I had the lever port turned straight up.
I did get some fluid out at the lever port. That's where my confusion lies.

I think my squeeze bottle developed a leak because I was squeezing it too hard trying to pressure force the fluid up and out.
I quit because it was getting dark and I had brake fluid all over the floor.

I'm going to give it another shot tomorrow.

I can order a kit but I really don't want to wait.
 

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Elitest thrill junkie
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I had the lever port turned straight up.
I did get some fluid out at the lever port. That's where my confusion lies.

I think my squeeze bottle developed a leak because I was squeezing it too hard trying to pressure force the fluid up and out.
I quit because it was getting dark and I had brake fluid all over the floor.

I'm going to give it another shot tomorrow.

I can order a kit but I really don't want to wait.
You really need a syringe for this.

Get syringes at the local drugstore. That's where I've been able to get them, just make sure it's big enough for what you need. Get tubing at the hardware store, it's for small engine fuel lines. Bring your syringe for proper fit, caliper if you can.

I had to bleed brakes on vacation recently, luckily it was Hope, but I still needed the tubing.
 
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