Swapping Magura brake hoses over

geebee2
geebee2 Posts: 248
edited August 2011 in MTB workshop & tech
I'm a newbie to MTB, my first bike was delivered today.

The front disc brake is on LHS, opposite to my road bikes, so I want to swap the hoses over.

The workshop manual ( page 11 )

http://www.magura.com/uploads/media/dow ... _2010E.pdf

says to remove wheels and push back the cylinders, stressing

"Never push back the pistons without the brake pads mounted! Open the brake
system only after having pushed back fully the brake pads"

However there is also an online video, which doesn't seem to do this step.

http://www.magura.com/en/products/disc- ... ovies.html

Maybe it's only necessary to push back the pistons when bleeding? It implies that bleeding may not be necessary ( I don't have a kit - yet ).

"Squeeze the lever blade several times (pump) to push the pads to their proper
position until the lever feel becomes very firm. If you cannot realize this, bleed the
brake (see page 16 onwards)."

Anyway, the video and the manual seem to be inconsistent.

My questions:

(1) Do I need to remove wheels and push back the pistons?
(2) What's the purpose of this?

Comments

  • nicklouse
    nicklouse Posts: 50,675
    which brakes?

    thats what happens when buying from mainland europe.

    remove pads refit wheel pump the pistons out (take care not to push them out of the caliper)

    swap hoses over then push the pistons home with the lever bleed port open to allow any air out. then pump the lever a few times to reset the pads. job done.

    if you are lucky a bleed will not be needed.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • geebee2
    geebee2 Posts: 248
    which brakes?

    Magura Louise 2010.

    Thanks for the help, but your advice seems to differ from what the workshop manual says... is the manual wrong in any way, or is this just an alternative approach? Actually I now realised that the video does show the wheel removed before the hose is removed, so I guess they just didn't show the first step.

    I don't have too good a feel for the conditions under which I will be "lucky". It seems a bit hit and miss, is this just characteristic of hydraulic systems? This is about air bubbles, yes? I don't have a good idea of why sometimes bleeding would be needed but sometimes it won't :?

    Maybe I should buy the bleeding kit first, but seems a waste of money if I never need it.