replacing front pads HELP

[new dixie]

when i pull the old pads out,the pistons will be out too much to fit the new ones yes???
will i have to remove the the master cylinder cap to push the pistons back in????
while im at it if i decide to give the calipers a good clean up can i do the pistons without having to bleed them,if i dont pop the pistons out????
cheers
dixie

[genisis]

Hi,
If you pop the piston out you will loose all your brake fluid so you will need to bleed them again. I found the best way to push the pistons back is a small g-clamp and slowly wind them back in. You shouldn't have to open the master cylinder unless you have to much brake fluid in the 1st place.

Hope that helps
Matthew

[dblanky]

before you remove the old pads get a long screwdriver or something and stick it between the old pads and use it as a lever to push the pistons in on both sides. problem I found with a g clamp is ther wasnt much room inside the caliper to get a clamp in.

You may need to drain some brake fluid off, I made the mistake of topping up the brake fluid a few weeks before when the pads were really low, when pushed back in there was far to much!

[VeetyR]

as above....with the old pads in use 2 screwdrivers to lever the pistons back.......make sure u have the cap off of the reservoir at the time.

If u are going the whole hog and take the pistons out......get new seals.....clean the pistons up and use red rubber grease when replacing them in the calliper( it is very important u use the right type of grease ).

If this is the first time u have done this and it turns out u need to replace the fluid.....do not panic if the lever comes back to the bar and the brakes do not appear to operate.

Keep pumping the lever(for maybe 5 mins) and u will feel the resistance build up(still with the cap off and topping up as you go).......then spend a few mins flicking the lever and u should see air bubbles returning to the resevior( this is air trapped in the top of the line).........when u dont see any more bubbling in the reservior, then u can bleed from the calliper.

If u arent replacing the fluid......a quick bleed and top up of fluid should suffice. VeetyR


Oh also : Make sure u wrap a decent sized rag preferably a piece of old towel around the base of the fluid reservoir when doing the above......it will save your paintwork should any fluid overflow.

[Stormin Ben]

Dixie,

It is unlikely you will need to remove the cap to push the pistons back -UNLESS someone topped up the brake resevoir when the pads were low

HOW TO
* Do one caliper at a time
* Remove the pads
*Clean the exposed pistons, the caliper body and area where the pads slide and the springy backplate/ cover thingy
*As previously stated, push the pistons back using the old pads and a big screwdriver or flat bar( If they've not been cleaned much before they may be quite stiff initially)
*What I do is then wedge 3 of the 4 pistons using either bits of wood or by holding the pads
*Then when you pump the lever only one of the pistons will move out
DO NOT OVEREXTEND IT I dont know precisely how far you can go but at least one worn pad thickness less than the centreline works for me
*With the piston out you can clean it (I just use a piece of old bed sheet)
*Then push it back in and repeat ON THE SAME PISTON
*Do this 4-5 times until its action is nice and smooth and you can easily push it back in by hand
NB if it wont go back in at any point, dont just assume its stiff, it might be slightly off square. Have a wobble round with it and try again
*Then repeat this procedure for the other 3 pistons and leave all 4 pressed fully in
*Once you are happy that all 4 pistons are moving nice a freely, apply a bit of copper grease to the pistons (manual says back of pad but to my mind that leaves a lot of unused grease sitting there gathering dirt)
*Carefully grease the 3 edges of the pad where it contacts the caliper and the backplate (NB not the forward facing edge as its not contacting anything) the edges of the hole the pin goes through and the springy backplate
*Fit the new pads, the springy plate and push the pin through & tighten it up
*Finally pump the lever a few times until the pads contact the disk and it goes firm (ooh-err )


Then repeat for the other side

Sounds a ball ache but its not actually that time consuming -maybe an hour total to do both sides
And it makes such a difference to the power of the brakes. Rather than half the force you apply fighting the friction in the pistons the whole lot goes into applying the brakes


Ben

PS what pads have you gone for?

[Stormin Ben]

Mike,

Wear rate was not a problem with these -my main reason for changing was that the initial power of the pads (that gives you the wow! factor when you first fit them) seemed to disappear as they got older
Also, they overheated on track

Other than that, a decent, well priced pad IMO


Ben