need brakeadvice asap
 

was trying to change front brakepads. took off old pads and tryed to press in the piston, but it wouldnt go in. opened the bleed valve, but it didnt help.

cant get in the new or the old pads

what should i do?

the caliper might be due to a overhaul. how can i get out the piston whitout using compressed air?

Some pistons need to be turned to wind them back in, can you pump the piston out by applying the brake? this would be the best way to get it out because it needs to be kept square and come out or in evenly.

hi there as jim says it sounds like you may have to pump the piston out useing the brake lever , just be very carefull , try to protect the piston so it does not fly out of the caliper . if you HAVE to REUSE the seals CAREFULLY REMOVE THEM and replace the same way round as they came out . YOU WILL need to clean the seal grooves out with something YOU NEED to get all the crap out, this can take sometime , lube the seals with clean brake fluid or rubber grease , same for the piston . the piston should slide in SMOOTHLY if kept sq , then fit the pads and bleed up . good luck zigzag

Gently squeeze the brake lever. This will straighten up the piston in the bore as I suspect you've pressed it in and got it ever so slightly tilted. You have to make sure you press it in from the centre - I use the old pads and a G clamp if available, or two spanners - place one across the face of the pad, then use the other in the jaw/ring of the spanner and twist.

Next time, you can use a screwdriver between the old pads before you remove them, and use that to pry them apart, which will push the pistons in.

It can also help to remove the lid on the brake fluide resevoir. If its still tough, you can use a small socket and put it on the piston, and hammer on it.

my caliper was due to a overhaul.

i piston didnt move mutch. i used the brake to try to press out the pistons for a wash and new gaskets, but i only got out one of the pistons. seems that i have to visit a friend with a compressor tomorrow to press out the last piston with air.

i tried to fix the main cylinder/hand leveler today, but didnt get out the lock ring.

Bikereurope,
do'nt think the compresor will do the job of removal now that the other piston is out, unless of course each piston on the caliper are completley independent of each other. You could replace the first piston part way back in and clamp it so that the other piston would expand out as you apply the brakes. I suppose one could do this with the compressed air, but might I recommend placeing a bit of thin wood across the other side of the caliper as air from the compresor will shoot it (piston) out like a cannon ball. so take care.
Clean all the parts with wire wool and make sure they are very clean before reasembly.
Good luck
Socks

I think you need to decide if you want to overhaul your calipers or just change your pads !

Were they giving you issues before the pads got low ??

Cleaning the pistons can help a lot. If you're going to change the seals, buy them before you pop them out..


I think the reason you can't get the pads in is because you've even moved the caliper on the bracket or done something with the anti rattle plates..


Obviously pushing your pistons in will help. Remove the top from the filler cap too !! Use a big tyre lever to ease the piston back in.


Leaving the pin out can help you get it all back together...

When you push out the pistons by puming the lever, use a big screwdriver between the pistons and the caliber (where the removed brake pads would have been), so when one piston is partially out, and locks at the screwdriver, the next one will go out just as long. Then use a smaller screwdriver, and do the same. At some point, one of the pistons will fall out, and the other will be almost out, and you can easely remove it.

Hope it makes sence.