Formula Rotors

386ka
386ka Posts: 479
edited October 2011 in MTB workshop & tech
Hi,

I am very pleased with my new Formula RX's, and they serve me well. The problem is, the rear caliper sits perfect on the 185mm Avid G2 rotor and mounting bracket, but the front needed another mounting bracket (presumably 180mm + a few washers), and now sits about a mm lower on the rotor.

It is not a problem, as the juicy's were also breaking on the rotor arms a bit, but I regard it as a performance issue not utilising the full rotor surface, so I am considering the following:
1. Do I just add a mm of washer under the caliper?
2. If I buy a new Formula rotor (front only), would 180 mm perform better than my Avid G2?

Am I better off with Formula rotors, do they heat up less, and do they bite better than my current setup? Also, should I go for 203 mm option?

Cheers,
Darko.
A much loved, Giant Trance X3 2010

Comments

  • 386ka
    386ka Posts: 479
    Anyone? Any imput will be of great help...
    A much loved, Giant Trance X3 2010
  • supersonic
    supersonic Posts: 82,708
    Not quite sure what you are asking in the first case - do you have a 185mm rotor, but only a 180mm adaptor?
  • nicklouse
    nicklouse Posts: 50,675
    a rotor is a rotor is a rotor the adaptor is what defins what size rotor you need.

    not all rotors are quite the size they say.

    I run some wavy rotors that say they are 180mm one set of Oros and they need a spacer to clear the tops of the waves.

    but again as above your question is not clear.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • 386ka
    386ka Posts: 479
    At the moment, I am using Avid G2 185 CS rotor + a shimano PM 180 adapter, including one cup washer to compensate for the small adapter. The problem is, the caliper is not sitting flush on the adapter (I think, as the bolts are a bit off), and also, there is about a mm of unused rotor surface, on the outer edge of the rotor (where pads dont make a contact).

    What I am asking is, should I try setting it up with another washers, or should I dump the experimenting and go for a 180/203 mm Formula rotor?

    On a side note, does a Formula rotor perform better than my Avid G2 (as in better bite, or better heat managment), regardless of rotor diametar?

    I am sorry I didn't make myself clear enough the first time...

    Thanks.
    A much loved, Giant Trance X3 2010
  • supersonic
    supersonic Posts: 82,708
    The rotors are much of a muchness. I'd either get the new 180mm rotor or the mount for the 185mm. If you are a heavy rider say above 16stone and want sharper braking, the 203mm may be worth it.
  • nicklouse
    nicklouse Posts: 50,675
    supersonic wrote:
    The rotors are much of a muchness. I'd either get the new 180mm rotor or the mount for the 185mm. If you are a heavy rider say above 16stone and want sharper braking, the 203mm may be worth it.

    bigger than 180 is not really needed :wink:
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • supersonic
    supersonic Posts: 82,708
    Neither is suspension, but hell, what we need and what we want ;-)
  • 386ka
    386ka Posts: 479
    Nope, I am not a heavy guy, about 70 kg without gear. The mounting bracket from the juicy 3 that I had before, somehow didn't fit. Can you recommend me one that will fit for sure?

    And you say that rotors are a much of muchness. Do you mean that there is no difference in performance between theese two? (except the Avid one is 5mm bigger in diameter)

    Thanks for the imput guys, I really appreciate it.
    A much loved, Giant Trance X3 2010
  • nicklouse
    nicklouse Posts: 50,675
    how did it not fit?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • 386ka
    386ka Posts: 479
    The brake caliper was not sitting flush against the tabs of the mounting bracket...
    A much loved, Giant Trance X3 2010
  • nicklouse
    nicklouse Posts: 50,675
    so it bottomed out elsewhere on the braket?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • 386ka
    386ka Posts: 479
    I think so, I can't remember well... But I am sure the mounting points were not in full contact...
    A much loved, Giant Trance X3 2010
  • supersonic
    supersonic Posts: 82,708
    Do you mean that there is no difference in performance between theese two?

    No perceivable difference.
  • 386ka
    386ka Posts: 479
    http://www.chainreactioncycles.com/Mode ... elID=64799

    This got me thinking
    64799.jpg
    If they supply cup and cones with their 180 adapter, that would explain the bolts not making full contact on the caliper...
    A much loved, Giant Trance X3 2010