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Formula Oro problem

DumpersDumpers Posts: 8
edited February 2010 in MTB general
I've Formula K18's and they seem to run with very little clearance between pads and rotor, can't even see daylight between them. Is this normal?

It appears the piston is not retracting back the same amount it did when new (4 months ago) as they are rubbing, slightly, almost constantly due to dirt/grit even after cleaning with wheel not running free. Anyone else found this with the Oro's, what's happening and what best course of action?

Cheers for any help with what is my 1st posting.

Posts

  • Remove pads, carefully push the pistons out a little bit and clean round them. Then re-set the pistons and ride.
  • llamafarmerllamafarmer Posts: 1,893
    Are the calipers correctly aligned?
  • Thanks for both replies.

    I'll give a wee clean and see how that goes.

    Yeah think the calipers are fine, the pads appear very very close on both sides so they're not misaligned on one side or anything. I've seen others that after braking have more distance between the pads and rotor - as if the pistons have retracted further back. I've heard shimano do that (more clearance) but don't have experience of any other type.

    This is my first hydraulic brake set (and first decent MTB) so finding my way.

    Cheers.
  • Is this happening on the front and rear or just one?

    What type of mount do you have on the front? Is it post mount or IS. Also what size rotors are you using and what fork - let me know this and I may be able to help... I solved the problem with my oro's last night.
  • nicklousenicklouse Posts: 50,675 Lives Here
    what has the mount got to do with it?

    all Oros are post mount.

    they do also run close.
    as already said resetting the pistons is a good step.

    Or just using them.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • It's happening more on the rear. Its a Cube Ltd Race 09 so everything as standard - Rockshox Reba SL forks, think its an IS mount, don't quote me though! 180 rotor front 160 rotor rear.

    Cheers for your thoughts.
  • Knew I shouldn't have answered the question on mount type - cheers Nicklouse. I'm able to ride but just keen on stopping the rubbing and obvious undue wear on the pads. When spinning the wheel the rubbing is enough to slow and stop the wheel after a few revs.
  • nicklouse wrote:
    what has the mount got to do with it?

    all Oros are post mount.

    they do also run close.
    as already said resetting the pistons is a good step.

    Or just using them.

    Aha Nick you'd be suprised. Yes they are post mount, but they still fit like mine on to an IS bracket.

    I sent my Rebas back this week to hopefully sort the leak and lockout out so I had to put my old RS J3s back on. Where the QR/axel had knarled away at the inside of the seat for the axel on the forks, they basically were pulling the fork in too much at the bottom. this meant the rotor was actually rubbing on the IS bracket (as well as the center lock disc HT2 nut gouging away at the fork).

    So take off the caliper (not bracket) and see if there is any rub, as there was with mine. I solved this by finding a lock nut (the outer one) that was no more than 1mm thicker than the one that was on my axel. This made the forks 'spread' by that 1mm which has solved the problem and brought everything back into line so the rotor no longer rubs the bracket. The tolerences are to say the least, tight.
  • I bought some k18s last year and they needed bleeding almost immediately, they ran super close to the rototrs then they just decided to be stuck on all the time.... funny that as I have bought 2 sets of oro puros for other bikes and they are fine.......
  • Cheers for the comments.

    I checked after Chunkers comments but don't think that's the problem, as I said it's more the rear its happening on. Perhaps a bleed and a good clean as previously suggested will do the trick. If that doesn't sort it I'll be back to the LBS as they're only 4 months old :?

    Thanks for all the posts. Cheers.
  • Just had a thought.

    If your prob is at the back...

    Why not take your front caliper off and put it on the back (I know the cable will be too short) but could be worth a go just to see if it runs smoothly with a different caliper as the caliper could be a bit bent or something else not quite right there and this would give you an idea to try and narrow it down?

    How straight are your rotors out of interest?
  • bails87bails87 Posts: 12,998
    Just had a thought.

    If your prob is at the back...

    Why not take your front caliper off and put it on the back (I know the cable will be too short) but could be worth a go just to see if it runs smoothly with a different caliper as the caliper could be a bit bent or something else not quite right there and this would give you an idea to try and narrow it down?

    How straight are your rotors out of interest?

    I doubt the hose would reach.
    MTB/CX

    "As I said last time, it won't happen again."
  • It will if it's not attached to the bars :wink:

    Didn't mean to actually use the front, just test for alignment
  • bails87bails87 Posts: 12,998
    Chunkers1980
    Ah right!
    MTB/CX

    "As I said last time, it won't happen again."
  • Rotors seem okay last time I looked. I'll check once home tonight, as you say might be worth a go.

    Although, one side (inside pad) looked closer all the way round when spinning the wheel as if the piston was perhaps becoming siezed. If that's the case will it need stipped down and rebuilt? I need to clean it and re-set the pistons like suggested yesterday.

    Thanks for the time taken to responding - much appreciated.
  • llamafarmerllamafarmer Posts: 1,893
    If one pad is more worn than the other could the calipers be trying to compensate, meaning they push one pad onto the rotor?

    You could try fresh pads and then realign.
  • I've been using new non std pads (aztec) which seemed very thick, swapped for a older set with still enough on, re-set the pistons and are now running much better.

    They do run close and one piston was certainly further out compenstating as you say. Struggled to push it back in so a further clean may do the trick but re-setting with 'thinner' pads seems to have done the trick.

    Anyone know which is best pads to use - Clarks, Fibrax, etc?

    Cheers for the help.
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