Why is my front brake spongy??? Help!

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#11

07-14-2015, 06:24 PM

Antonio Balls

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I agree it is very frustrating. The spongy brake lever does not instill confidence that you will have enough brake if/when you need it. Keep at it though. It is a very basic system and you know that a small bubble is causing you the grief. As I said in an earlier post it took a two hundred mile ride with lots of stopping to move the air bubble out of my system. It has been rock solid since.

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#12

07-14-2015, 06:59 PM

splattttttt

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Quote:

Originally Posted by jmerchant.1

Might have to try that method next. I'm still baffled...I bought one of those syringes and did the reverse bleeding method. It seemed to work and my brake got firm but sure enough, the next day it was totally soft again. I just don't understand what is causing this. Like before it will get firm if I pump the lever enough but I shouldn't have to do that every day. It seems somehow air is slowly entering the line even with the bike sitting in my garage. What could be causing this?? Grrrrrrrrr!!!

at this point, it can only be air leaking in.
master cylinder diaphragm or banjo bolts loose?

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#13

07-14-2015, 07:03 PM

jmerchant.1

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Quote:

Originally Posted by splattttttt

at this point, it can only be air leaking in.
master cylinder diaphragm or banjo bolts loose?

Nope, both are tight. I'm not sure how else air could be getting in.

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#14

07-14-2015, 07:13 PM

The old guy

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make sure you use the dot 5 fluid --dot 3 will never pump up

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#15

07-14-2015, 08:28 PM

jmerchant.1

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Quote:

Originally Posted by The old guy

make sure you use the dot 5 fluid --dot 3 will never pump up

But the label on my master cylinder says to use dot 4 only. I've been using "valvoline synthetic dot 3&4 brake fluid" from autozone. That should be fine right?

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#16

07-14-2015, 09:10 PM

neilpp

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Quote:

Originally Posted by The old guy

make sure you use the dot 5 fluid --dot 3 will never pump up

Need to know the year of the bike before you state that. IIRC 2006+ Dynas all use DOT 3/4. Prior years use DOT 5.

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#17

07-14-2015, 09:15 PM

jmerchant.1

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Quote:

Originally Posted by neilpp

Need to know the year of the bike before you state that. IIRC 2006+ Dynas all use DOT 3/4. Prior years use DOT 5.

It's a 2013

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#18

07-15-2015, 08:49 AM

jjminch

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Might have a worn seal somewhere. Could be the banjo crush washers, or maybe the calipers/MC need rebuilt.

Did you re-tape your bleeders? If you've been working bleeders on and off for a while, the teflon tape might be worn out and allowing air to pass.

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#19

07-15-2015, 11:17 AM

izhd

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Also, you can get brake pressure pump fromharbor freight for $25
I was doing Tokico conversion and due to many reasons bleed brakes like 5 or 6 times (yeah, I know)
With pump I did it last time in under 5 min..

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