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Problem fiiting new pads to sierra rear calipers..
DanP - 1/1/06 at 03:21 PM

Hi folks, happy new year to you all,

I'm hoping somone will be able to help me out, I'm putting the back brakes together on my luego viento and I can't seem to get the pistons to retract far enough to fit the calipers around the new pads and discs.

I'm using standard sierra pads and discs an the total thickness of pads and disc is 36mm and yet the pistons won't go back any further than about 34.5mm - any suggestions please?? (the calipers are only a year old) If anyone could measure how wide their calipers go or the total thickness of the pads and discs that would be really appreciated as I'm totally flummuxxed!!

Mr G - 1/1/06 at 03:24 PM

I take it your rotating them and applying pressure as you do it?

Previous Post HERE


Cheers


G

[Edited on 1/1/06 by Mr G]

DanP - 1/1/06 at 03:35 PM

Hi G,

I'm rotating them with the key from an angle grinder that fits nicely into the piston grooves, I am applying pressure as i rotate - not any massive amoutn of force though.

DanP - 1/1/06 at 03:40 PM

Thanks for the link, i did do a search but obviously missed that one,

I will give it a go applying more force as i rotate the piston.

Cheers.

Mr G - 1/1/06 at 03:42 PM

As the other thread i've linked to - Best bet is to use a hand clamp or similar, you'll know when it 'bites' and starts retracting, otherwise you'll be just rotating it forever

[Edited on 1/1/06 by Mr G]

DanP - 1/1/06 at 03:50 PM

Thanks, worked perfectly, i thought i had been applying enough pressure already as I had already made it retract but it obviously needs more for that last bit.

Had to put it in a vice with a piece of wood as a sort of thrust washer to let me rotate the angle grinder key.

Much happier now! Thanks again!

billy - 1/1/06 at 04:39 PM

cor i had some fun with mine nice new ones will turn in easy without force

Genesis - 2/1/06 at 11:46 AM

quote:
Originally posted by billy
cor i had some fun with mine nice new ones will turn in easy without force


But where's the FUN in that eh? ;P

britishtrident - 2/1/06 at 11:52 AM

Applying too much pressure can ruin the self adjuster mechanism.
They should wind back with fairly gentle but firm pressure if they don't most likely the hand brake cable is too tight. Slacken off the cable and check the levers on the calipers are fully back before starting to wind back the pistons.

Then when re-tensioning the cable ensure there is enough free motion to let the self.-adjusters work,