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i luv my Leesaa
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Discussion Starter · #1 ·
hi, i was riding home today from work and i noticed that a few times when i used my front brakes my lever would go in pretty far with a little bit of pressure, my brakes usually grip inch or less before my front brakes engage,
I would have to release my lever and re-engage my front brakes for it to stop, this would only happen at random times, after using my front brakes a few time it would go away, i did a search but nothing really in relation to low brake pads causing this to happen. thanks in advance. -mark
 

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i luv my Leesaa
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Discussion Starter · #3 ·
i took a closer look at my front brakes, they seem a little low but i can still see the middle groove inside each pad but the pistons are out a good amount, so im betting they might be low, going to have my front pads replaced at a local shop and see if the problem still persists, i checkd my MC the fluid is full and clear
-mark
 

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Sounds like you need to re bleed. Check for air and bleed your brakes. I'd do this first as it is a much cheaper option than buying new pads. You could very well have the same problem after buying pads and not checking your lines in the first place.
 

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Sounds like you need to re bleed. Check for air and bleed your brakes. I'd do this first as it is a much cheaper option than buying new pads. You could very well have the same problem after buying pads and not checking your lines in the first place.
:stupic
 

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i luv my Leesaa
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Discussion Starter · #8 ·
thanks for the input everyone, i havnt been riding lately been a bit busy, going to my buddy's house to work on my brakes this weekend coming up, getting a set of metzeler m3's and going to slap on some new pads n rebleed the whole system with new fluids =):YEA
 

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i luv my Leesaa
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Discussion Starter · #9 ·
so.... i replaced my brake pads, rebleed the whole complete system correctly. and everything was okay for a little bit of riding then suddenly i'll loose pressure in my lever again, today i bought a big jug of brake fluid and kept bleeding for a good 20 to 30 minutes, used up about 1/2 the jug of brake fluid and i noticed air bubbles coming out from the bleeder nipple when its fully closed! anyone have any input?
Thanks in advance =(
-Mark
here is a video to help out, sorry about the focusing had to hit record as soon as i closed the valve air bubbles started appearing already

 

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Discussion Starter · #10 ·
i have the bleeding system setup like a siphon, so theres no air coming up from the catch bottle if this helps a little also =(
 

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Looks to me like you are just sucking air into the bleed tube because it's not an air tight seal over the bleed nipple and you have some vaccum pressure sucking the fluid/air up. If you just put the bleed tube on with out the pressure and then do the old pump up the lever, crack the nozzle and close method you likely wont get all those bubbles in the tube.

Otherwise you can try to put some vaseline or thread tape, etc around the nipple to try and get an air tight seal on the bleed line and use the vacuum method.

If you actually had that much air in the master cylinder you would definitely not have firm feel on the lever even just sitting there.

If the lever gets soft after riding for a while try: go ride until it gets soft, come in and bleed the master(the old way) then put a zip-tie on the lever(not fully pulled in, just get a little pressure on it) for like 30 min and bleed the master again. No guarantees but hey at least it'll keep you busy for a while.
 

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Discussion Starter · #12 ·
bleed tube is completely air tight
mc lines calipers bled correctly using old school traditional method
all bleeder valves are completely closed
I have a firm feel in the lever but after a few pulls while riding air is getting into the mc from somewhere :(
 

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If you simply put the tube over the bleed nipple I'm pretty sure it's not completely air tight. For the most part it doesn't matter, but you can see that the air moves over top the bleed nipple when it is sucked in by the vaccum so when you open/close the nipple while using the vaccum it is possible to catch some air in the MC. Anyway, it's not impossible air is leaking in from somewhere as you ride and with out being there checking things out nobody really knows, but from the video what you are seeing is likely not air coming out of the MC so I would look elsewhere.

Even though you are sure you have an air tight seal and my theory is wrong you could easily give yourself a quick sanity check by taking your air tight siphon setup to another bike and see if the same thing happens.
 

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Discussion Starter · #14 ·
air bubbles are coming into the tubes from inside the bleed nipple the bleed hose is pretty damn tight fit over the nipple, the bleed nipple is also completely closed all the way maybe it's the check ball inside the bleed nipple like you said who's knows right
 

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Discussion Starter · #15 ·
thanks for the advice tho imma head over to the local bike shop tomorrow and pick up a new bleeder nipple/valve n hope that solves the problem :/
 
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