Rear break lever spongy

slinkydonkey
slinkydonkey Posts: 27
edited May 2017 in MTB workshop & tech
Hello

So on my MTB which is a Trance 27.5, 2
Which as Shimano M615 180mm/160mm brakes and levers.

I replaced the pads but the break lever is still spony? do the brakes need bleeding ? and is that easy?

Cheers
Paul

Comments

  • LimitedGarry
    LimitedGarry Posts: 400
    Brake bleeding is quite easy, but you need a special kit for it and mineral oil. Depending on what's available on the market, the kit can be expensive enough to make it an investment not worth your while.
    On the other hand, having the kit allows you to slightly overfill the brake knowingly, which reduces the lever's free stroke and to a great degree reduces or even eliminates sponginess. This is something that really has to be done carefully, as overfilling the system too much may cause issues.
  • cooldad
    cooldad Posts: 32,599
    I don't do smileys.

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  • The Rookie
    The Rookie Posts: 27,812
    Or it's just taking time for the pads to settle back on the discs, if it didn't need a bleed before you changed pads it's even less likely after when you have more fluid in the resevoir!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • poah
    poah Posts: 3,369
    What Rookie says, you might have to get the pads closer to the disc to reduce the lever pull before the make contact.
  • The break leaver was spony even before i changed the pads, it's why I changed them to be honest.
  • The Rookie
    The Rookie Posts: 27,812
    Have a look at the pads as you squeeze the lever, if they have to move too far before contacting the disc it makes the lever spongey, compare to the front as well. But yes it does sound like they need a bleed.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • 02gf74
    02gf74 Posts: 1,168
    The Rookie wrote:
    Have a look at the pads as you squeeze the lever, if they have to move too far before contacting the disc it makes the lever spongey, compare to the front as well. But yes it does sound like they need a bleed.

    I disagree - the lever may more further but once pads contact disc, the lever should feel solid. Definitely worth bleeding the brakes.
  • The Rookie
    The Rookie Posts: 27,812
    One person's spongey is another's long travel.......
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • bobbydigital
    bobbydigital Posts: 254
    Thanks for the replies, I've tried all those things, will just run it as it is for a while and see how it goes.