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  1. #1
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    203mm rotor onto an old Z3 bomber(100mmtravel),OK?

    I was wondering if I could "stick" a 203mm rotor to an old bomber z3(2k1),without worying about excessive stress onto the lower legs,could anyone enlighten me please? the brakes:sram 9.0 disc-similar to old xt hydraulic,or grimeca system8.and should I stick to classic round-style rotor or move on to a "wavy",and why?I`m more concerned with brake fading,due to overheating on long steep DH, than looks=)TNX alot!

  2. #2
    Portland, OR
    Reputation: todd_freeride's Avatar
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    is your fork a QR ? or a 20mm ... I wouldn't recommend it, I'm not sure that fork was designed for anything over 160mm. better safe than sorry.
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  3. #3
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    maybe take my chance with a 180 rotor?

    Quote Originally Posted by todd_freeride
    is your fork a QR ? or a 20mm ... I wouldn't recommend it, I'm not sure that fork was designed for anything over 160mm. better safe than sorry.
    sadly my fork`s a QR model.I want 2 buy a new marzo 55 or 66,but for now(very low budget )I have to keep on thrashing these ol faithful z3`s.so what do u think about mounting a 180diameter rotor(maybe not as risky as with a 203 one...)?

  4. #4
    Portland, OR
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    I think you'll be okay with a 180. The thing people are scared about is that the force of an 8" rotor combined with a QR axle is a REALLY bad idea... me? I've never had a problem with QR/8" combo's maybe I've been lucky, I dunno.

    Only thing that actually scares me, is that its an old fork...8" might be just a little too much stress for it.

    So I'd go ahead, put a 7" rotor on there, watch the fork, if its really flexing under braking, then back down to a 160mm. make sure to check the tension on the crown bolts. And just keep in mind, its an old fork, no hucks to flat
    [SIZE="4"]Ibex bikes[/SIZE]

    2007 Ibex Trophy SS
    2006 Jamis Komodo 3.0
    2006 Ibex Zone FR-1
    2004 Special-Ed P.2 A.1

  5. #5
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    I've been running 203mm rotors on a Z5 for at least 4 years and have had no problems.

    Tim

  6. #6
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    sad to say man, but stick to 6 inch and nothing bigger
    the trick is ENJOYING YOUR LIFE EACH DAY, don't waste them away wishing for better days

  7. #7
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    Marzocchi's guidance is stanchions less than 32mm (your fork) are limited to 160mm; 32mm and greater can go up to 203mm.

    Personally, I would cautiously run a 185mm rotor, but for XC use (hmmm... Downhill / Freeride forum... uh, scratch that). Marzocchi is worried about the leverage exerted on its lowers and IS tabs under maximum braking.

    The skewer issue is something altogether different, and depending on whom you believe (there is *GASP* debate on the ol' internet over the disc brake wheel ejection "problem"), is something to be dealt with by using a good quality skewer (i.e. most Shimano, new Mavic) and ensuring it is properly tightened on a regular basis.
    speedub.nate
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  8. #8
    thats not to steep is it?
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    specizlied FSR XC pro's come stock with a 203 rotor in the front. and the fork is a QR rockshox reba sl. and ive had no problem what so ever except the fact that its too power ful so i went down to a 160.
    07' fsr xc pro
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  9. #9
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    Quote Originally Posted by thatdownhillkid
    specizlied FSR XC pro's come stock with a 203 rotor in the front. and the fork is a QR rockshox reba sl. and ive had no problem what so ever except the fact that its too power ful so i went down to a 160.
    Like I was saying, dropout type is entirely a different matter. To address this, companies like Fox, Magura, Niner and Dean are producing forks with "forward facing" dropouts, to minimize the risk of possible wheel ejection.

    But in the case of your Reba, with 32mm diameter stanchions, Rock Shox is only looking at fork / tab strength when they recommend a max rotor diameter of 210mm.

    Note that this is about the same maximum as 32mm Marzocchis.

    Rock Shox could care less about the type of dropout, and assumes that your QR is strong and tight.

    Whether or not you subscribe to the vertical dropout / disc brake ejection theory, forward facing tabs seem like a great preventive idea. I'm betting they'll go that route in another year or two.
    speedub.nate
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  10. #10
    s62
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    oh crap...
    I just had my lbs upgrade my 6" rotors on my QR Manitou Minute 3 130mm fork to 8" rotors... Is this ok?!?
    09 Specialized Enduro SL Expert
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  11. #11
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    Quote Originally Posted by s62
    oh crap...
    I just had my lbs upgrade my 6" rotors on my QR Manitou Minute 3 130mm fork to 8" rotors... Is this ok?!?
    According to Single Track World, according to Manitou you're ok!

    http://www.singletrackworld.com/article.php?sid=1228

    Again, ain't got nothing to do with QR.
    speedub.nate
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  12. #12
    s62
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    ah, thanks a ton, mate... you just saved me a big headache (figuratively and literally )
    Thank you
    09 Specialized Enduro SL Expert
    w/ E150 and Command Post

  13. #13
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    so,I have the same fork generation,same brakes!

    check this:same fork,sram discs,the same combination as mine,and 180 disc.so I figure that works ,no problem!
    Attached Images Attached Images

  14. #14
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    and this is where I foun it: http://www.nsmb.com/gear/sramdiscs_12_02.php

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