I drained my hidraulic calipers by mistake.

marcos 22579

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So I was changing my break pads for the first time and noticed that the pads in the rear hit the disk even if I adjusted the 2 alignment screws. The rotor is a bit wobbly. I was under the impression that the torx screw was to adjust the pump pressure, thus making the gap between the pads and disk a bit wider. I did made the gap wider because when I pressed the break lever a gush of fluid came out. Now that break lever almost hit the grip and feels "loose" not as hard to press as the front break lever.

Is there a way to put more hidraulic fluid to the pump or adjust the lever like in mechanical breaks?
 

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I think you are going to need something like this to get your brakes bled. I have not had the chance to mess with hydro brakes.

Only other recommendations I could make would be to take it by a bike shop & have it bled.
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So, on your brake lever, you'll see another torx screw ....before you do anything, level that whole lever out where that torx screw
is level, if not just a bit on the upward side.

Then an easy way is an old slow way. Open that torx screw on the lever reservoir and take a syringe with mineral oil in it then slowly add
some to that hole.

After that just lightly and slowly tap the lever until you see fluid coming back up and slightly bubbling out...just don't let any come all the way out
When it gets to the top let it settle back down...Rinse...... Repeat... a few times until it seems like it cannot be filled anymore.

Then go ride and see how it works.

hope that helps.
 
Be careful that you don’t get any fluid on the rotor or brake pads. The rotor can be cleaned with alcohol, but the pads may be ruined.

Each manufacturer has their own way of bleeding brakes. Some use mineral oil and others use DOT fluid. They are not interchangeable and not all mineral oil is the same or even compatible.

If in doubt, take it to a shop. Brakes are too important to take chances with. Best of luck moving ahead.
 
Be careful that you don’t get any fluid on the rotor or brake pads. The rotor can be cleaned with alcohol, but the pads will be ruined.

Each manufacturer has their own way of bleeding brakes. Some use mineral oil and others use DOT fluid. They are not interchangeable.

If in doubt, take it to a shop. Brakes are too important to take chances with. Best of luck moving ahead.
Those ZOOM calipers use the mineral oil.
I actualy just had to add some to my Aventure which are the same caliper/brake system of ZOOM.

I think Aventon now uses Tecktro or somethin.

Oh for sure new pads if oil got onto them, like @Django said :)
 
I Mcguiver myself a "drain kit". Didn't drain anything really. I added oil using the syringe without the plunger. I pressed it in the hole, put oil from the top as you do with a funnel and press the break lever a couple of times. It drank down half a syringe. Then I filled to the top with a couple of drops and put the torx screw back. The lever has its normal pressure again. I will use the bike today for a couple of miles. When I get the drain kit tomorrow, I'll drain the whole thing and learn the process. BTW what are the symptoms of an air bubble in the brake lines?
 

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I Mcguiver myself a "drain kit". Didn't drain anything really. I added oil using the syringe without the plunger. I pressed it in the hole, put oil from the top as you do with a funnel and press the break lever a couple of times. It drank down half a syringe. Then I filled to the top with a couple of drops and put the torx screw back. The lever has its normal pressure again. I will use the bike today for a couple of miles. When I get the drain kit tomorrow, I'll drain the whole thing and learn the process. BTW what are the symptoms of an air bubble in the brake lines?
I hope that you at least used the unscented baby oil. Air in the brake line will give the lever a spongy or rubbery feel at best, and no braking at worst Case.
 
Update: There was a lot of air in the line. Almost half a syringe. I put an extra shim on the caliper block thinking it would give me some extra gap between thr rotor and the pads. I think it did because it is not doing the same intermitent hissing sound when rotated. Now It's working like it was before.
 

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Update: There was a lot of air in the line. Almost half a syringe. I put an extra shim on the caliper block thinking it would give me some extra gap between thr rotor and the pads. I think it did because it is not doing the same intermitent hissing sound when rotated. Now It's working like it was before.
It's always good to learn things eh? :)
 
How many miles does the brake fluid lasts? I changed the pads at 400 but the fluid didn't looked dark.
A internet ebike youtuber said, once a year on brake fluid replacement or when servicing brake pads. I'm not sure if that's right, but sounds legit to me.
 
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