Cleaning brake calipers

Whats the best stuff & way of cleaning your calipers? Im changing pads on sat & wanna clean the calipers up aswell but dont want to use anything thats going to ruin the seals!

Cheers

i used wurth brake and chain cleaner, works well :slight_smile:

remember to copper grease the back of the pads when you put the new ones in :slight_smile:

I normally use a tin of brake cleaner, Wurth is normally pretty good, and a toothbrush.

Pump the pistons out, give them a spray of brake cleaner then use the toothbrush to give them a good clean up.

Sometimes I’ve needed to use a bit of emery cloth at the ends of the caliper where the pads locate if they are really dirty. When you fit the new pads, a bit of copperslip on the back of the pads and some where they locate in the calipers works a treat :slight_smile:

I heard that copper grease can gradually destroy the caliper seals - read it in Ride magazine years ago - as an alternative they recommended Super Caliper Grease’ from GP Products 01543 876238 - I bought a tub years ago and have used it ever since to coat the backs of the pads and the pistons (after cleaning them first with metal parts/break cleaner). I still use copper grease on the pad retaining pin because this doesnt come into contact with the pistons (and by extension) the caliper seals.You can phone them up on the number above to either order it directly from them or find a stockist. (thanks for reminding me - I need a new tub!)

Is it always necessary to replace the seals when cleaning brake calipers (the Haynes manual reckon you do) ?
When I changed the front pads on mine one of the pistons was pretty stiff but I didn’t clean and rebuild the caliper cos I didn’t have any spare seals…

I’ve stripped many a caliper since owning bikes and only ever replaced 4 seals in calipers (none of which we fluid seals - only dust seals)

The main important thing to do is to clean the gap in which the fluid seal sits in, a small watchmakers screwdriver or the rotary wire brush on a dremel does a real good job!

and use red rubber grease on the seals when you put thenm back together again…

i allways use molycote grease on the backs of the pads

Q - what exactly does the copper grease on the back of brake pads do?

They don’t move or are tightened to the degree that they wouldn’t drop out when they are loosened, right?

The main reason its to reduce friction between the pads and the pistons so they don’t SHREEEEEEEK every time you brake.

and to stop the pad and the piston corroding together, apparently.

yep thats right - the manufacturers only ever say about changing things like that as they have to cover their own backs from a liability point of view. Lou’s bike is 17 years old and the caliper piston seals were fine - I changed them as a precaution but only because of their age and because I was completely rebuilding them. Make sure you never get any copper slip ont e piston surface though - acts as liquid sandpaper over time! LOL

NAh, you don’t need to replace the seals everytime you change pads, but do check em.

IF you’re gonna do em proper you need to pull the whole lot of and bleed your system. IF you’re gonna go that far you seperate all the bits out anyway, so just make sure everythin’s cleaned off before putting her back together. THat said, probs can occur cos stuff bed’s in but if you disturb it, then it doens’t always goback together so smooth.

Strip the caliper down, wire brush the crud (but do wear a mask cos pads can have asbestos fibres… depnding on the make), copper grease the moving parts, shunt the pistons back in, fresh pads, re-bleed, piece of ****, but patience on the re-bleed

Speaking of which… anyone know what kits needed to refill from the bottom, pumping down from the top is such an arse, specially with hard lines… .?

Hi,

You can use a syringe and pipe to fill from the bottom but it is far easier to use a Mityvac (Hein Gericke do something similar) as it works by vacuum pressure to drag the fluid through. I wish I had bought one years ago after messing about with conventional bleeding.

As it is my first post the bar is open:)