Which are the truest rotors

antfly
antfly Posts: 3,276
edited December 2010 in MTB workshop & tech
Hello mountain bikers, it's mountain biking season for me and my rear juicy 7 is rubbing.
I'm quite experienced with avid brakes now so i've tried all the tricks and I think it's just that the Avid rotors all have a significant wobble, so does anybody make rotors that don't have a wobble or at least less than Avid ?
Smarter than the average bear.

Comments

  • i dont think any rotors are made with a wobble on purpose!

    My shimano rotors are very stiff though, haven't had any problems with warping.
  • nicklouse
    nicklouse Posts: 50,675
    they are all the same.

    there are a few truing guides in the tech link sticky above.

    none of my avid rotors have a wobble.

    sure your bearings are OK?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Bent axels, hubs, mounting points and frames can play a part too - may not all lie with the disc.

    All the Avids I've used have been not different to any other branded ones.
  • antfly
    antfly Posts: 3,276
    I've just serviced the hub, it just needed a bit of grease and the bearings were ok. I suppose bent axle is possible, i`ll check that.
    One of my rotors has a very definite wobble though but it sounds like it's not worth trying another brand.
    Smarter than the average bear.
  • jairaj
    jairaj Posts: 3,009
    All brands should be straight, obviously you get some manufacturing faults or damage in transit.
  • nicklouse
    nicklouse Posts: 50,675
    bent axle will not cause the wobble just the disc to run at a single angle of the perpendicular to the axle.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • antfly
    antfly Posts: 3,276
    It won't be that then.
    Smarter than the average bear.
  • The Rookie
    The Rookie Posts: 27,812
    Easiest check is remove disc and lay on a flat surface, if it lays flat its not the disc, if it doesn't it is!

    The only disc I've had that was irredemely 'wobbled' was an Avid, the circumference had become to big for the radius and I could 'pop' the centre across back and for within the outer disc, straighten it and one ride later it was warped again - binned.

    Simon
    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.
  • cavegiant
    cavegiant Posts: 1,546
    Shimano is quite open that their larger rotors have a bit of a wobble.

    The straightest I have used are also Shimano, but their fancy floating rotors.

    The RT-76 is the best rotor I have used, very true and strong.
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?
  • antfly
    antfly Posts: 3,276
    Thanks for the tip on the Shimano ones.

    Putting the most obviously wobbly one I have on a flat surface, it doesn't lay completely flat, FWIW.
    Smarter than the average bear.
  • Have yo checked your rotor thickness?

    I bought a Superstar rotor which wasn't the same thickness all over - varied by about 0.1mm so it always rubbed. Drove me nuts until I had it reground at work. Fine after that but not everyone has access to a fully equipped toolroom...
  • mattv
    mattv Posts: 992
    All rotors I have ever had worked with have a small amount of wobble. Try and gently true them by hand or with a specific tool. Avid, Shimano, tektro, Hope, all slightly out of true by the time they are fitted.
  • stubs
    stubs Posts: 5,001
    Out of all the rotors I have used (Avid,Hope,Formula,Shimano,Hayes,Ashima) the only one that was wobble free when new and stayed true is an 180mm EBC I bought about 4 years ago its well worn now and on my commuter Hardtail but still no wobble. It has got so hot the brake boiled and the rotor went a lovely deep blue still stayed true. Only thing and its not a problem it weighs about twice as much as my current rotor on my susser and makes the brake squeal when wet.
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • CraigXXL
    CraigXXL Posts: 1,852
    cavegiant wrote:
    Shimano is quite open that their larger rotors have a bit of a wobble.

    The straightest I have used are also Shimano, but their fancy floating rotors.

    The RT-76 is the best rotor I have used, very true and strong.

    +1