El Caminos pistons creeping

Simonb256

Hi all,

I just got the GT back today after having a hose replaced and bleeding both.

I changed the pads also seeing as they are literally running off the metal.

I noticed one thing, the pistons keep slowly creeping out. I havent ridden it yet as the front wheel is practically stuck fast.

I push the pistons is carefully with a flat bladed screwdriver and it goes back in with little effort, but in 5/10 mins they just creep back out again, regardless of whether I use the levers or not.

I am running the powerdial things on minimum now and it seems a little better but still doing it.

Any ideas as to why they are doing this?

It has been suggested that it could possibly a leak of some kind letting air in the system.

nicklouse

how does the lever feel? spongey? then air. hard then too much fluid.

Simonb256

I take it too much fluid then as they are not spongy in the slightest, well the were until i changed the pads,now there isn't room for the pads to move enough to be that spongy heh.

cheers for the advice

alaric@epicmtb

Check that the reach adjustment screw isn't moving.

It's a design fault on both my 'Nines and El Caminos that the reach screw walks over time, and for some reason on the El Caminos if the screw is too far in/lever too far out, it can cause the pistons to start to jam on.

Alaric.

Simonb256

that is a point to be honest, as thedo seem to occasionally re-adjust themselves mid-ride. Thuogh i keep seeming to have to put the levers really far out, though this was due to an issue I was having where I just lost braking ability after an hours riding almost totally.

I'll have a play in the morning [:D]

nicklouse

simon if they were bled with used pads in and the pistons not retracted then now you have fitted new there will be too much fluid in them.

Simonb256

figures,

Thanks for making it clear to me mate. I was hoping that wasnt really the case but ahh well, back to the LBS i guess and get them to sort it, I hate playing with such things.

nicklouse

simon it is not that hard as all you need to do is let some fluid out.

Simonb256

true true,

Though its things like:
How much fluid?
Where am I letting it out from?

...and stuff like that.

Im guessing just over a smidge, and to let some out reservoir end?

I have a habit of breaking such things, via having ago then feeling like I have to end up botching something to work heh.

nicklouse

Mmm have a read of the manual.

does not matter if it comes out of the lever or the caliper. just make sure you dont get any fluid on the pads.

ok then LBS time.

alaric@epicmtb

Letting a small amount of fluid out is very easy.

It's a bit of a three hand job, so extra help is good but not essential.

On the caliper end there is a bleed valve - has a rubber dust cap on it if you haven't lost it.

Fit a 6mm (?) spanner on this and then hold a piece of kitchen towel over the bleed valve.

Loosen the bleed valve and squeeze the lever in about 1/2 its travel. DON'T LET GO OF THE LEVER

Now tighten the bleed valve, now you can release the lever.

Now test and repeat if necessary.

Alaric.