Couple of things RE brake servicing.

[Dave20046]

...Could do with the orgs views on a couple of things that've crossed my mind while servicing my calipers:
1) There's a bit of surface rust on my pistons, this is the worst one. Reckon it's passable if I tidy it up a little?


My brakes were crappy so I've bought new seals, a couple of the old seals were visibly damaged. Just don't wanna waste the new seals if they'll die straight away.




2)
I didn't think the old caliper banjo bolts were strainless so I bought stainless replacements, however the threads are actually in good condition. Can anyone tell for certain if this is a stainless bolt? (the short one, the long one 100% is s/s)





Bit of grotty brake porn:






Apologies for the mega pics

[Dave20046]

Looking back on the poor pictures, you may not be able to help!

That bolt appears to have a corroded head and although the threads are perfect it's defintiely a more yellow colour than the definite s/s bolt.

[dirtydog]

Give the piston a good clean up, I use autosol or the grotty ones like that and yo'll be surprised how they come up. Only once have I had a piston that was beyond help (well actually it was 2) but they were from Thedonals bike which was in particularly bad condition

I reckon that rust will come off as well with a bit of brake cleaner then autosol, or just autosol if you dont have brake cleaner.

[Dave20046]

Tried both, got to admit to sinning with wirewool

[Spanner Man]

Good morning all.


Use 1200 grade wet & dry, with silicone lubricant, or WD40 type stuff, & elbow grease.
You'll be surprised at how well the pistons will clean up, & If you use a fair helping of rubberlube upon reassembly, your seals will last for ages.

The bolt looks like a standard steel one with what's known a yellow chromate finish. The best way to tell if it's stainless is to try to stick a magnet on it, as stainless steel is non magnetic it wont stick.


Cheers.

[Dave20046]

cheers for that spanner man,
one more question, what direction am I best rubbing down the pistons in? (if it matters atall) up & down (the way the pistons move) or side to side? (around)

[timwilky]

rubbing down definitely around and not up/down.

If you can, get a rubber bung and fit a nut/bolt with large washers either end through it and insert into the piston and tighten.

As the bung compresses it will expand out to grip the piston.

Place bolt shaft in secured drill/ lathe etc and spin, polish to your hearts content.

Originally Posted by dirtydog

Give the piston a good clean up, I use autosol or the grotty ones like that and yo'll be surprised how they come up. Only once have I had a piston that was beyond help (well actually it was 2) but they were from Thedonals bike which was in particularly bad condition

I'm never gonna live that down, am I?

Got to do the front brakes again soon- pray for me...

[Dave20046]

laavley - cheers folks

WD40 + 1200 W&D'd the bad bits then polished up with autosol and a rag. Can't feel any sharp bits or mounds & dips in the surface anymore.