Getting pistons out

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Man_Named_Dave
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Getting pistons out

Post by Man_Named_Dave » Sun Apr 22, 2012 1:20 pm

What do you guys use to block off the air passages (after you've parted the caliper halves), both the rubber seal holes and especially the passages at the back of where the piston sits? I can't do it properly!

Neosophist
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Re: Getting pistons out

Post by Neosophist » Sun Apr 22, 2012 3:25 pm

Man_Named_Dave wrote:What do you guys use to block off the air passages (after you've parted the caliper halves), both the rubber seal holes and especially the passages at the back of where the piston sits? I can't do it properly!
You can't do it like that, you'll need a piston extrator..

Easiest way it to pump the brakes with the calipers all conencted up to move the pistons out a lot so they are touching (clamp any free moving pistons with cable ties to force the others to rise)

Then when you split the calipers you can pull them out with some mole grips and cloth (most times you can wiggle them out with your fingers.
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vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

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Re: Getting pistons out

Post by arsey30 » Sun Apr 22, 2012 3:43 pm

Clamp the seal holes with mole grips or vice over cardboard and poke a pointed rod [scriber] in the holes in the base of the piston bores.
Always works for me after a few goes.

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Lane
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Re: Getting pistons out

Post by Lane » Mon Apr 23, 2012 11:36 am

In the past i have fashioned up a jig for getting stuck pistons out, I used a 50-60mm long bolt and use a rubber grommet preferably about 20mm long and cylindrical and two washers that fit inside the piston, tighten the nut and as the rubber compresses, it will expand and grip the inside of the piston and twist and pull and it should come out.

Now i just use internal pliers.

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Man_Named_Dave
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Re: Getting pistons out

Post by Man_Named_Dave » Tue Apr 24, 2012 6:46 pm

I got them out and just checked the outside diameters of all 8.
Now either the Haynes manual has ballsed up, or I have RVF calipers, or they are all wayyyyyyy below service limit.

The manual says the upper piston's limit is 31.94 and mine are all around 30.23
For lower, it says 30.14 is the limit and mine are all around 25.35.

Anyone know what's going on?

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