pistons/calipers.

I need to get the front brake pistons out of the calipers but can't get the calipers off the bike, is it possible to remove the pistons clean them and replace with new seals without taking the calipers off?
Never worked on disc brakes before so need advice please.

Faighaigh

 

I don't think so , but it might be possible. The caliper really needs to come off in order to rebuild properly. Why won't the calipers come off? Are the bolts stuck, try some penatrating oil on them.

 

Bolts are stuck solid and I'm worried that they may shear off, been soaking with penetrating oil for three weeks and it don't seem to have made any difference at all.

Faighaigh.

 

Do you have access to an air wrench?

The calipers really do need to come off; there would be virtually no way to get into where you need to get cleaned out with them still mounted.

 

Keep working to get them out. They have to come off in order to remove the fromt wheel. Have you tried a inpact wrench or breaker bar? Be sure to use a 6 point socket and not a 12 point. The 6 point will grip the bolt better.

 

you can remove the front wheel without taking off the calipers but that wasnt the case was it

 

Use a 6-Point Socket, a Breaker-Bar and a Rubber Mallet or a Hard Wood Hammer Handle.

Or-- A SEARS Craftsman 1/2" Drive Hand IMPACT Tool with a 6-Point Socket.

You are probably fighting the LOCKTITE used to secure the Calipers last time they were removed.

The Sears Impact Tool will make it easy to remove those Bolts.

You can still apply Impact to them by applying moderate undoo torque to a Socket and a Breaker Bar ... then, ... Whacking the Handle of the Breaker bar with a Rubber Mallet of a Hard Wood Hammer Handle ... or, ... the Handle of a Wooden Baseball Bat that you cut-off and hide the big-end from your little brother and swear you never saw it. (But, you did "Saw" it.)

 

Thanks for the replies fella's.
Not sure what a breaker bar is we probably call it a different name, no access to any air tools or impact driver. I'll have a word with our village postman (a biker) and see what tools has.

Faighaigh.

 

i just did a pair the forks were off the bike. put a good wrench on it smacked it a few times then a ratchet with a short pipe for a little more leverage worked good. a bit rough on the person holding the forks. my 3/8 impact wouldnt break them loose. i didnt get big daddy out that was next that would of got them for sure here is a picture of a braker bar

 

A Breaker Bar and a 1/2" Drive - 6-Point Socket ...
Or, ...
The "New-style" Power-Socket -- (Designed to apply the Turning Torque on the Flat of the Hex ... NOT the Point.

I have seen guys forgo the Impact and just put-on some "Heavy" force.
They get the Breaker Bar situated at 9 O'Clock or 1o O'Clock and just plain STAND and HOP on the Bar to get the Bolt to break loose.

 

Try as I may I could not get the pistons out so I took them to a local guy who's a good mechanic (recently found him) and he couldn't get them out either. Only recourse was to split one of them and then we saw the marks of the mole grips looked at the other one gain and could see where some prat had tried to turn the piston with a chisel!!!

But I now know that the new seals I bought from ebay are the wrong one's though the supplier is happy to exchange them. And the brand new battery I bought for the K75s, also from Ebay, wont take a charge.

If the fridge packs up and the beer get's warm I think I'll open a vein.

Faighaigh.