Brake pistons stuck?

[Az]

Front wheel on the bandit wasn't spinning freely when i span it round with the front wheel elevated.
So i took off the brake calliper, noticed the brake pistons were poking out a bit (which i assumed isn't normal, or is it?) so i pulled out the nearest pad, decided i'd give the pistons a bit of a clean so pumped the brakes and just kept pumping them until the pistons wouldn't come out any further (assuming this is where i went wrong), cleaned the pistons up and then when i tried to push them back in they won't budge... they're seriously stuck out and it feels impossible to force them back in.
What can i do to get the pistons back in?
Any advice would be great as i'm sat here in my garage awaiting replies lol

https://i789.photobucket.com/albums/yy178/AzAndBikes/IMG_9329_zps7d015fdf.jpeg

[iooi]

G Clamp.

Slacken off the master cyl cap as well.
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[Az]

[Kickstart]

Hi

Depends why they are stuck out.

What often happens is that there is a build up of corrosion behind the seals, which push the seals out hard onto the piston. In this case you need to pop the pistons fully out, remove the seals, clean up the grooves the seals live in (thoroughly) and reassemble.

What could have happened is that you have tried to push the pistons back in but not got them quite square and they have jammed.

All the best

Keith
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[Az]

[Nobby the Bastard]

Get some water-pump pliers and then try applying pressure in different places ount the edge of the piston until it moves in.

Don't forget to remove the cap off the master cylinder.

If you don't know where the master cylinder is, sell the bike. If you don't know where it is, you are too stupid to ride a bike....
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[yampug]

put rag over master cylinder unless you want brake fluid over everything when you push the piston in.

[Az]

[Blau Zedong]

[Az]

[Kickstart]

[Az]

I'm thinking of just having the brakes refurbed at a mechanics as i'm most likely to fuck this up... and i'd rather have my brakes done properly.

[Nobby the Bastard]

To clarify,

The piston will be slighly lopsided in the the barrel. Even being a fraction of a degree off of straight will make it hard to push the piston back in.

By working round the edge of the piston with waterpump pliers you'll find the point where you are then pushing on the side that will straighten the piston in the barrel, so it'll go back in again.

You'll need to repeat to find the sweet spot until it's all the way in.

As the Oracle said, get the pressure on the piston from the side where the brake pads would sit and the outside of the calliper.[/b]
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[_Iain_]

[poleposition]

As mentioned they will be slightly lopsided, the best way to get them moving again without damaging the seals would be to rotate them with a decent pair of grips, I would probably advise against simply forcing them back in, If the piston is jammed against one of the seals you may end up splitting or damaging it.
as you have got the pistons out this far you may as well remove them completely and clean them up. You will be able to remove the seals at the same time and give those a good clean too, and then refit with some suitable lube (not grease)
Just bear in mind that rebuilding is a lot harder than taking apart and requires patience, and sometimes another pair of hands.
The main seal isn't a problem, The dust seal can be tricky.
As you freely admitted yourself if you are unsure then get someone else to do it,
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[Ripp3rCrust]

https://www.youtube.com/watch?v=EDfNb_9YkcI&feature=youtube_gdata_player

This video and the follow up I found to be highly useful when working on the Bandit's calipers. May be useful to you in case you end up fully rebuilding them, or just to get a general sense of their workings
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Current: '05 CBR600F - Previous: '01 GSF600S Bandit, '06 XR125