Spongy Brakes

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clarkee
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Bike owned: fzr400
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Spongy Brakes

Post by clarkee »

As you all know brakes on the 3tj always been top notch but since I had an off few months ago (bike ended up upside down against the tyres) mine have been really spongy.

Had them off, cleaned out calipers and replaced the fluid, even tie wrapped the lever back overnight but still the same, comes right back to the bar. Any ideas?
Q007
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Bike owned: FZR 400 1wg 1986 FZR 600r 1995
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Re: Spongy Brakes

Post by Q007 »

could be bent/warped disc/discs. mine had 1 disk that when laid flat looked like a breakfast bowl and was spongy as hell.

Q
Evilchicken0
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Re: Spongy Brakes

Post by Evilchicken0 »

A warped disk will do that ... the brakes will bleed and be hard until you move the bike then they'll be soft again, pump them with the bike soft and they're hard again.

If they just won't bleed in then you could have a piston locked or some air behind it.

Lastly you could have popped a seal in the master cylinder so the fluid isn't being pumped.

Swap a few bits out from a working system to see if it makes a difference - it could be an excuse to get a radial master
clarkee
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Posts: 35
Joined: Sat Jun 14, 2008 7:33 am
Bike owned: fzr400
Location: milton keynes
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Re: Spongy Brakes

Post by clarkee »

Evilchicken0 wrote:A warped disk will do that ... the brakes will bleed and be hard until you move the bike then they'll be soft again, pump them with the bike soft and they're hard again.

If they just won't bleed in then you could have a piston locked or some air behind it.

Lastly you could have popped a seal in the master cylinder so the fluid isn't being pumped.

Swap a few bits out from a working system to see if it makes a difference - it could be an excuse to get a radial master
Cheers guys, looks like the master cylider I think.

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