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Discussion Starter · #1 ·
Okay, so I was changing my brake pads, for some nice fancy Galfer premium ones..

I managed to get them out okay... but then I couldn't for the LIFE of me get the new ones in.
So I phone bikerboy and he suggested I remove the calliper from the forks.

That was were the first problem occurred. Eventually, I managed to get the stuck bolts loose, and free the calliper from the forks and remove it.

Now, the reason I couldn't get the new pads in of course was because I needed to push the pistons back to make space. No joy, they simply refused to budge. Eventually... out came the mallet.

Now, the mallet was working great, I was slowly pushing one of the pistons back in place, when suddenly I am covered in brake fluid!! The other piston had come FLYING out of the calliper, dumping it's entire contents of brake fluid in a rather projectile fashion.

So I managed to push that piston back in to the calliper, and figured out how to reattach the little clip that came off.
Luckily the pistons were now flush with the calliper and I was able to get the new pads in, and back on the bike.

NOW, my problem was bleeding the system, because of all the fluid that was lost and replaced with air.
A LONG time later, my brakes started biting!! So I kept bleeding until no more air would come out...

I took the bike for a quick spin around the block,and the good news is that it stops. Eventually.
Rather, the brakes have plenty of stopping power, it just feels....

It feels like I am stopping my bike with a pillow. REALLY soft and spongy. BUT, it is a very STICKY pillow, because it does actually have a lot of stopping power, even if the brakes give no resistance themselves. It is a really weird senstation.

I shall be going to the garage in the morning I think to get them checked over...
 

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Okay, so I was changing my brake pads, for some nice fancy Galfer premium ones..

I managed to get them out okay... but then I couldn't for the LIFE of me get the new ones in.
So I phone bikerboy and he suggested I remove the calliper from the forks.

That was were the first problem occurred. Eventually, I managed to get the stuck bolts loose, and free the calliper from the forks and remove it.

Now, the reason I couldn't get the new pads in of course was because I needed to push the pistons back to make space. No joy, they simply refused to budge. Eventually... out came the mallet.

Now, the mallet was working great, I was slowly pushing one of the pistons back in place, when suddenly I am covered in brake fluid!! The other piston had come FLYING out of the calliper, dumping it's entire contents of brake fluid in a rather projectile fashion.

So I managed to push that piston back in to the calliper, and figured out how to reattach the little clip that came off.
Luckily the pistons were now flush with the calliper and I was able to get the new pads in, and back on the bike.

NOW, my problem was bleeding the system, because of all the fluid that was lost and replaced with air.
A LONG time later, my brakes started biting!! So I kept bleeding until no more air would come out...

I took the bike for a quick spin around the block,and the good news is that it stops. Eventually.
Rather, the brakes have plenty of stopping power, it just feels....

It feels like I am stopping my bike with a pillow. REALLY soft and spongy. BUT, it is a very STICKY pillow, because it does actually have a lot of stopping power, even if the brakes give no resistance themselves. It is a really weird senstation.

I shall be going to the garage in the morning I think to get them checked over...
i have the galfer pads
maybe your pistons need grease like when i did my ones at chin house
you need brake piston grease
i would clean the disc make sure no oil are grease on there
 

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Discussion Starter · #3 ·
i have the galfer pads
maybe your pistons need grease like when i did my ones at chin house
you need brake piston grease
i would clean the disc make sure no oil are grease on there
Is the Piston SUPPOSED to fall out? :S
 

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could be the seals are gone is fluid coming out of the pistons ?
 

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Discussion Starter · #6 ·
only way they come if you pull on the brake lever while the pads are out
It was whilst I was pushing on ONE piston.
Okay, just checking that it IS supposed to happen, and that it is okay that I simply pushed it back in...
 

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It was whilst I was pushing on ONE piston.
Okay, just checking that it IS supposed to happen, and that it is okay that I simply pushed it back in...
oh you can try cleaning the piston and grease them see if that work
 

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Discussion Starter · #8 ·
I aint taking it apart again.
I just GOT it all together!

Although, I noticed the brakes were very very hot indeed when I got home..
but that may be just because they are new and I was using them excessively.
 

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I aint taking it apart again.
I just GOT it all together!

Although, I noticed the brakes were very very hot indeed when I got home..
but that may be just because they are new and I was using them excessively.
seem like they rubbing and not going back in ill ask chin in the morning he like playing with stuff like that
 

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see what Yamaha say, they may well advise you claim on your warranty/fork out for another caliper, in which case the one that Bikerboy linked is perfectly fine.
 

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see what Yamaha say, they may well advise you claim on your warranty/fork out for another caliper, in which case the one that Bikerboy linked is perfectly fine.
i think it's going to be new caliper is bike 08 no warranty
 

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Discussion Starter · #13 ·
But what is wrong with my Calliper?
I put the Piston back in...
It works, just a tad spongy!
 

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oh, so this is just a story, Fisher? i thought you were asking for advice. if it fell out but you've managed to pop it back in, after a while it should feel okay.
 

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Discussion Starter · #15 ·
Yeah, sorry :p
It came out, and I managed to get it back in.

The brake works, just very very spongy.
I also just wanted to clarify that it IS meant to come out, and that I wont be slowly leaking my brake fluid or something..
 

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No it's new pads on old discs, give them time to bed in, once they are, all will feel normal again. When you bleed the front, if you take the reservoir lid off and leave it off, squeeze the lever gently and bubbles should be seen. Keep an eye on the level. Leave the lever overnight with a zip tie holding the lever on, then bleed the next day, this should get all the air bubbles to one place, and bingo, super responsive braking, but most of the feel will be pads bedding in.

Please do not beat pistons with a mallet, g-clamp at worst and slowly sqeeze the pistons back in carefully and parallel, prevents damaging seals.

If you want to check for leaks, again assistant/zip tie/strap the lever tight, then look for leaks. If whilst they are applied the lever feels like it is creeping back to the bars, this would indicate a slow leak, it will eventually reach the bars if it is a leak, but otherwise be warned it can feel like it's creeping just because you are being hypersensitive to it thinking there is a problem.
 

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Discussion Starter · #17 ·
Yeah, I gathered it was the bedding in that made it feel like a sticky pillow.

Thanks for the cable tie idea!!!
I did try pumping the lever, and got a lot of air out.
I will try your idea :D
 

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Not questioning you Benji, but I thought brake fluid was Hygroscopic, wouldn't leaving it uncapped overnight be a bad idea?
Or am I getting it slightly wrong, and that's just for storage over long periods of time?
 

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Not questioning you Benji, but I thought brake fluid was Hygroscopic, wouldn't leaving it uncapped overnight be a bad idea?
Or am I getting it slightly wrong, and that's just for storage over long periods of time?
Probably didn't make that clear, not suggesting leaving the reservoir open over night. Pump the lever till it goes firm, then lock it off with a zip-tie, then in the morning, gently crack open the bleed nipple, should get the last piece of air out. Only remove the reservoir top, when you first start, that way you can see when all the bubbles have come out. I don't tend to touch the bleed nipples, till I have got the air out of the top, by pumping, then start on the bleed nipple. Vacuum bleeder kit is spot on as well, been very pleased with mine, makes these jobs very easy.
 
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