Disc brakes and quickrelease skewers ???- Mtbr.com
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  1. #1
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    New question here. Disc brakes and quickrelease skewers ???

    I recently switched to disc brakes. The LBS told me I should turn the QR around so the handle is on the right side. I did, but I find it a lot harder to change/reinstall the wheels, especially the rear. I've seen some guys with disc brakes with the QR on the left pointed forward and up between the chainstay and seatstay. One guy had the QR pointed straight back parallel to ground. Any thoughts? Does it make any difference which side the QR handle is on ???

  2. #2
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    I think the shop owner just doesn't want you to sue him if you burn your fingers on the hot rotor.

  3. #3
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    I was told the same thing

    Quote Originally Posted by XCBob
    I recently switched to disc brakes. The LBS told me I should turn the QR around so the handle is on the right side. I did, but I find it a lot harder to change/reinstall the wheels, especially the rear. I've seen some guys with disc brakes with the QR on the left pointed forward and up between the chainstay and seatstay. One guy had the QR pointed straight back parallel to ground. Any thoughts? Does it make any difference which side the QR handle is on ???
    I was told the exact same thing, and here's why: there is more stress on the axle on the rotor side (due to the braking being applied on that side). For safety reasons, it is better to put the QR on the "less stress" side (opposite the rotor, on the right). Not only is mounting the QR on the right side supposed to reduce strain on the QR itself (which should reduce the chance of it breaking or loosening up), it is also supposed to be a little more stable should the QR loosen up.

    I tried running the QR on the right side for about 1 month. Then I just got so fed up with the difficulty with removing the rear tire that I decided to forgo the advice and mount the QR back on the left side. Old habits are sometimes so hard to break.

    And if you look around, you will notice that >90% of those with disc brakes also mount the QR on the left side.

    Thx..Doug

  4. #4
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    Quote Originally Posted by dgangi
    I was told the exact same thing, and here's why: there is more stress on the axle on the rotor side (due to the braking being applied on that side). For safety reasons, it is better to put the QR on the "less stress" side (opposite the rotor, on the right). Not only is mounting the QR on the right side supposed to reduce strain on the QR itself (which should reduce the chance of it breaking or loosening up), it is also supposed to be a little more stable should the QR loosen up.
    That doesn't make sense. The QR does not feel any stress at all from disc braking, since it's the axle that takes up the stress from disc braking, by being pressed into the dropout. The QR is also a double-sided thread, which means that either end can turn to loosen/tighten so it doesn't matter which side you put the QR lever on. There are no safety issues with which side you put the lever on, there is only the convenience issue. Traditionally people have put the QR lever on the non-drive side to avoid getting grease and gunk on their hands when operating the QR.

    Quote Originally Posted by dgangi
    And if you look around, you will notice that >90% of those with disc brakes also mount the QR on the left side.

    Thx..Doug
    That's because of tradition, not any stress issues.

  5. #5
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    Quote Originally Posted by XCBob
    Does it make any difference which side the QR handle is on ???
    No, it doesn't. Put it where you feel more comfortable.

  6. #6
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    Quote Originally Posted by dgangi
    I was told the exact same thing, and here's why: there is more stress on the axle on the rotor side (due to the braking being applied on that side). For safety reasons, it is better to put the QR on the "less stress" side (opposite the rotor, on the right). Not only is mounting the QR on the right side supposed to reduce strain on the QR itself (which should reduce the chance of it breaking or loosening up), it is also supposed to be a little more stable should the QR loosen up.

    I tried running the QR on the right side for about 1 month. Then I just got so fed up with the difficulty with removing the rear tire that I decided to forgo the advice and mount the QR back on the left side. Old habits are sometimes so hard to break.

    And if you look around, you will notice that >90% of those with disc brakes also mount the QR on the left side.

    Thx..Doug
    I always have my QR on the Left side but after reading this I think I may change them over to the right side. I have always run them on the left but I would hate to come off the bike from some freaky accident.

    Trevor!

  7. #7
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    The further away from objects

    Quote Originally Posted by XCBob
    I recently switched to disc brakes. The LBS told me I should turn the QR around so the handle is on the right side. I did, but I find it a lot harder to change/reinstall the wheels, especially the rear. I've seen some guys with disc brakes with the QR on the left pointed forward and up between the chainstay and seatstay. One guy had the QR pointed straight back parallel to ground. Any thoughts? Does it make any difference which side the QR handle is on ???
    Is the best i have mine on the left (non driveside) with the handle parallel with the fork leg. In the back its on the non rdriveside and tucked behind the brake caliper. Ive found only one instance where i looked down to find the QR released and the only thing holding the wheel in place was the disc rbake and lawyer tabs.

  8. #8
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    When I raced with QRs I ran the rear on the disc side, and the front on the non-disc side. Purely for ease of use was my only goal. The front is easier to use since theres more more. Look at alot of racer pics and such. I've noticed about 80% running the QRs run just this way. I use bolt ons for racing now, and run my QRs the old way now. Go figure.

  9. #9
    Fragile - must be Italian
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    Forces on the QR

    Quote Originally Posted by Juramentado
    That doesn't make sense. The QR does not feel any stress at all from disc braking, since it's the axle that takes up the stress from disc braking, by being pressed into the dropout.
    That is not an accurate statement. The QR AND the axle both feel the stress from disc braking. As the rotational force of the wheel is reacted upon by a brake caliper affixed to the frame or fork, the axle itself and what holds the axle in place (QR in this case) all are stressed. And since the disc is on the left side, the left side of the axle actually gets stressed a little more than the right side.

    I was told by a number of wheel builders that the quality of a QR and the axle material makes a big difference with disc brakes. The manual for my Magura Marta disc brakes also says the following:

    "Install the wheel by positioning the rotor between the brake pads and fixing the wheel in the dropouts. Close the quick relese of your wheel which you should mount on the opposide side of the brake caliper and tighten it sufficiently".

    I asked my Magura dealer and my wheel builder why the manual states this and they both gave me the reason listed (safety - stress on QR). But with that they also said "but that's what the manual states...I still run the QR on the left side and have not had any problems".

    Thx...Doug

  10. #10
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    Keep it simple...

    If you are concerned at all about your wheel coming loose, use bolt-on skewers. If you want to use QR, use them with the release on the side you prefer. The failure of this system to work is based on the ability of the mechanism to clamp the axle between the frame/fork dropouts. I have heard some talk about skewers coming loose on disk systems - but then again I heard of skewers failing on V-brake wheels too... hmmm... sounds like there wasn't enough force to clamp the axle in either case...

    Just my thoughts...
    GEVELTERSCHMIDT RACING

  11. #11
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    Quote Originally Posted by XCBob
    I recently switched to disc brakes. The LBS told me I should turn the QR around so the handle is on the right side.
    One guy's opinion... stress is no different on either side, if the skewer is not tightened properly either side can slip, loosen your wheel and pull it and you'll see this. And if you have those little "lawyer" tabs or a ridge (like Marzocchi) on the fork dropouts, you can see how difficult it is for a wheel to come out, even if it has just come loose (so stop!).

    Quote Originally Posted by XCBob
    I did, but I find it a lot harder to change/reinstall the wheels, especially the rear.
    Yup, and too much going on with the derailleur/cable on the drive side to mess with there for me, why make things any more of a PITA for yourself?

    Quote Originally Posted by XCBob
    One guy had the QR pointed straight back parallel to ground.
    That's what I do. Then it can't snag on anything, while I can still grab it. And the front skewers on my bikes are all on the left pointing up.

    Only thing you see fork manufacturers (Fox Forx in particular) warning about is not to use an 8 in. rotor in a QR fork (another topic).

    Dave
    Just Passing Through: eatin' dirt & crappin' dust

  12. #12
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    Eh, should not make a difference

    ...apart from fit and the bunt finger factor. As far as the stress goes, the QR is a free floating rod sprung on both ends. If it losens up, it won't matter what side the lever is on, there will be equal gap on both sides, apart from tension in the springs.

    I have my front QR on the right, just because that's the only place it fits when closed. it just so happens to cover my damping adjuster knob, which is kinda sticking out in the breeze, which is an added bonus. I hate to smack that thing on a branch, shear it off and loose it.

    As far as load direction goes, the front brake will force the axle out of the dropout under heavy braking with a loose QR, so keep an eye on it. Some have gone as far as to recommend avoiding Ti skewers with a front disk brake, but I say they are just trying to cover thier hides. There have been instances of large brakes ejecting front wheels, but these were more cases of prototype forks without lawyer lips, and loose/failed QRs. More in the fluke departement than a real danger, IMO. Just do a QR check before each ride, which you should do anyway.

    I avoided using my Ti skewers with disks, but then I just went ahead and installed them anyway. Heh, as if 50 shaved grams was worth my life, eh?
    Aw, what the heck...

  13. #13
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    Quote Originally Posted by dgangi
    That is not an accurate statement. The QR AND the axle both feel the stress from disc braking. As the rotational force of the wheel is reacted upon by a brake caliper affixed to the frame or fork, the axle itself and what holds the axle in place (QR in this case) all are stressed. And since the disc is on the left side, the left side of the axle actually gets stressed a little more than the right side.
    That's not true at all, and a simple force diagram will show you that. First, the axle is what takes up the counter-force from a disc brake. This is quite obviously shown when you release the rear QR and ride the bike; you can brake quite well without the QR tightened, because the axle is pressed against the dropout by the brake force. This is different from the front fork, where the brake torque tends to press the axle out of the dropout.

    The rotational force of the wheel has nothing to do with it, since there is no such thing. Any rotational force which is present on the wheel is isolated from the hub and the axle by the bearings. The bearings are not able to transmit any torque at all (otherwise your wheel will not rotate freely).

    Therefore, the rear disc brake does not affect the QR at all. In any case, both ends of the skewer are threaded and therefore able to be loosened. It doesn't matter which side the lever is on, both ends can turn.

    Quote Originally Posted by dgangi
    I was told by a number of wheel builders that the quality of a QR and the axle material makes a big difference with disc brakes.
    This is only crucial for the front wheel, since the placement of the disc brake caliper is such that the braking force tends to push the axle away from the dropout, and therefore a loose QR will take your front wheel off when disc braking.

    Quote Originally Posted by dgangi
    The manual for my Magura Marta disc brakes also says the following:
    "Install the wheel by positioning the rotor between the brake pads and fixing the wheel in the dropouts. Close the quick relese of your wheel which you should mount on the opposide side of the brake caliper and tighten it sufficiently".
    I asked my Magura dealer and my wheel builder why the manual states this and they both gave me the reason listed (safety - stress on QR). But with that they also said "but that's what the manual states...I still run the QR on the left side and have not had any problems".
    Thx...Doug
    I wouldn't trust the Magura manual for technical accuracy. The Magura manual also states that the spokes of your wheel should be pointed a certain way when using disc brakes. This is nonsense, since disc brakes have very little effect on spoke tension, they are symmetrically placed, and this effect is spread over the number of spokes you have. I especially wouldn't trust Magura salespeople on engineering principles, since these are the same people who are unaware that larger rotors exert larger forces on the caliper mounting tabs.

    As I've stated, don't take my word for it, have an engineer draw you a force vector diagram of the forces involved and see for yourself that there is no stress-safety issue with the rear QR and disc brakes. There is especially no issue with which side the QR lever is on, since once the QR is tightened, BOTH sides have the same clamping force.

    The front wheel, on the other hand, is a different story altogether. Here, which side the QR lever is on still doesn't matter, but the tightness of the QR is crucial.
    Last edited by Juramentado; 02-08-2004 at 08:18 PM.

  14. #14
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    Quote Originally Posted by airman
    If you are concerned at all about your wheel coming loose, use bolt-on skewers. If you want to use QR, use them with the release on the side you prefer. The failure of this system to work is based on the ability of the mechanism to clamp the axle between the frame/fork dropouts. I have heard some talk about skewers coming loose on disk systems - but then again I heard of skewers failing on V-brake wheels too... hmmm... sounds like there wasn't enough force to clamp the axle in either case...

    Just my thoughts...
    How are bolt on skewers any better than quick release skewers?

  15. #15
    The Top Cap Guy
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    I run my skewer on all my disc bikes on the conventional side (non-drive).... I thought that some manufactures recommended the qr lever on the drive side because some quick release levers (I know older Salsa levers especially) could be "closed" into (and touching) the rotor causing HUGE trouble... so to eliminate any problems with what skewers you would run if you have the lever on the drive side of the bike this would not be an issue.

    I run the newer Salsa skewers that have a stop built in to them so the can't touch the disc. You can tell if your Salsa's are the newer style by looking at the laser etching on the lever... if you have a Pepper logo and the words "open" on the inside of the lever - that's the new style with the stop, so you can't hit the disc. SO by that theory - Salsa would have you keep the lever on the disc side of the hub - hence their modification to the skewer.

    And on the force per side to side in the fork to quick release.... doesn't the quick release tighten on both sides EQUALLY? So it shouldn't matter which side the lever is on... if it is going to loose - both sided of the quick release will loosen at the same rate.

    Just my 2 cents.... (if it's worth that much)
    FF
    "If I'm leading, I'm bleeding."

  16. #16
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    Theres a few reasons. Theres been some serious testing regarding deflection and such by those German mags. Its been determined that to get the QRs tight enough to be at the needed preload, they would have to be hit(beaten)with a hammer or equal. Also, it was found that main thing that affected how much a given set of QRs deflected(on some high tech "deflecto-meter" hell i dunno)was the design of the QR, not so much as the material(some camps say ti stretches easier because ti IS weaker then steel all things being equal, and can let the forks deflect more from lateral loads, and for a short periods of time, there could be air under your dropouts instead of the alxes. Also they could possibly lock the front rotor from a sudden misalinment(which we know would suck)from the same stretching/flexing) Also some say ti they break sooner. So...steel boltons are the rule when I race. They are a 3rd lighter then ti QRs(put a magnet on that bigass swivel thingie..its all steel)cause there just not much there, its faster if setup right before hand. Its "steel", so its as strong as one can get as far as I'm concerned. And, I can tighten it like any other "real" axle should be, with a wrench.Ya gotta pull out your kit anyway, cause its gonna be a flat if your taking the wheel off. The 6mm L shaped allen is rubberbanded to the tube right next to my bigair and plastic tire iron. For my everyday riding(like today), i like the convience of the QRs. No contest. Big epics i use the boltons as well.

    My race bike weighs 22lb even. Its axles are steel boltons. Prob literally the only steel left on the darn thing...

  17. #17
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    Thanks guys !

    Thanks guys ! I'll be flipping my rear QR skewer around to the left(old school) and leave the front on the right. I learned a lot from the posts... namely make sure the QR is TIGHT.

  18. #18
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    Skewers

    I run both my front and rear on the drivetrain side so that there is no chance of getting grease and oil on them or bending them if you slip. I run the rear straight up and the front up in front of the fork leg. This has been working well for 3 years so I'm going to keep doing it that way.
    Formerly Travis Bickle

  19. #19
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    'cuz you can make 'em tighter

    Quote Originally Posted by frank n. beans
    How are bolt on skewers any better than quick release skewers?
    and still get them off. granted, you can use gorilla strength on a QR but it will be next to impossible to remove. With bolt on, you just crank it down.

    YR

  20. #20
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    Quote Originally Posted by frank n. beans
    How are bolt on skewers any better than quick release skewers?
    Bolt-on skewers are beneficial for the front wheel only (probably why they're only avaialble with front hubs!). What this affords is an axle that cannot be displaced by the braking counter-force from the disc brake caliper. On the front fork, the placement of the disc brake caliper is such that whenever you brake, the axle experiences a force which tries to push it out of the dropout. The only thing that prevents the axle from being ejected is the clamping force on the QR, or in the case of a bolt-on, there is nowhere for the axle to go since it's effectively mounted through a hole, not a dropout.

    In the case of a front wheel QR, if the clamping force is not enough, repetitive disc braking may jolt the QR slightly out of the dropout, after which the rider's weight and bumps on the trail tend to push the axle back to its original position. After this happens several times, the QR can loosen further, which means that it becomes easier for the axle to move back and forth on the dropout until the QR gets loose enough that the wheel gets ejected. All this has a low probability of happening, since the lawyer lips will prevent catastrophic ejection of the wheel (so don't file them off!). Judicious checking of your front QR if you have disc brakes will also help make sure your QR is tight enough.

    How tight should a QR be for front disc brakes? That's the million-dollar lawsuit question. An ambiguous answer is, tight enough for the QR to "bite" into the fork dropout, but not tight enough that you break either the skewer or the dropout tabs. A safety precaution also is to mark the QR ends with a felt pen and place corresponding aligning marks on the dropouts, so that you can check whether the QR is loosening or not while in use.

  21. #21
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    Quote Originally Posted by Yeti_Rider
    and still get them off. granted, you can use gorilla strength on a QR but it will be next to impossible to remove. With bolt on, you just crank it down.

    YR
    But you don't need to gorilla-tighten bolt-ons, since the axle is held in place by the hole in the fork, and not by the skewer. In fact, it's quite damaging to the hub bearings if you overly-tighten the skewer.

  22. #22
    "Ride Lots" - Eddie Mercx
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    wasn't entirely my point

    Quote Originally Posted by Juramentado
    But you don't need to gorilla-tighten bolt-ons, since the axle is held in place by the hole in the fork, and not by the skewer. In fact, it's quite damaging to the hub bearings if you overly-tighten the skewer.
    my point being that a regular QR can only get so tight since it's a cam. if it's too tight, it never comes off. But, due to wear on the plastic bushings, or just not getting it tight enough before engaging the cam, it may be a bit looser than with a bolt on.

    the whole disc brake with QR problem is a farce anyway. while a QR may have become disengaged due to disc breaking forces on rare occasions, the potential for catastrophic frame failure is still more likely. But, that's my entirely unscientific opinion based purely on the fact that I hear a heck of a lot more about broken frames than I do about a QR coming off due exclusively to disc brakes.

    YR

  23. #23
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    Quote Originally Posted by Yeti_Rider
    the whole disc brake with QR problem is a farce anyway.
    I wouldn't call it a farce, since there is at least one guy who's had a catastrophic front wheel ejection using his disc brakes; Google his website under "quick release and disc brake problems". I think the jury is still out on just how often this happens.

    Quote Originally Posted by Yeti_Rider
    while a QR may have become disengaged due to disc breaking forces on rare occasions, the potential for catastrophic frame failure is still more likely. But, that's my entirely unscientific opinion based purely on the fact that I hear a heck of a lot more about broken frames than I do about a QR coming off due exclusively to disc brakes.
    YR
    I think your anecdotal evidence is accurate. While an analysis of the QR-disc brake setup shows that disc brake caliper placement on all forks is definitely not the best in terms of the direction of force applied on the axle while braking, perhaps most people using this setup do check and tighten their QRs adequately.
    Last edited by Juramentado; 02-09-2004 at 12:14 PM.

  24. #24
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    One little tidbit more..After having a QR come loose a couple of times over as many months a year ago or so, I made some observations. The front is where the concern is. Agree 100%. When they do lose tension(and they do sometimes if neglected enough or its a bad design or of course just plain worn out)the lever will usually spin around with the wheel rotation and usually drop or hang sorta. Sooooo...I took to pointing my front lever staight up all the time. Used to place it that way, but also about half the time it was horizonal tucked up under the caliper. The main reason is this...with it pointing up and back I can always see it at a glance(which means this is one of those few applications that bright colors really do help). Easy and fast, and very reasuring. It has saved me 2 times since. I remember once glancing down(at speed) and in disbelief I saw no lever. That fast. I stopped and in even more surprise it was completely loose. Pointing to the ground. Yes indeedy. Also, if anything gets stuck in the wheel or rotor and then happens to spin around, if the levers under the caliper(and its free to spin at anytime as only friction keeps it from doing so otherwise)it can be driven up with possibly measurable force up again the caliper itself thats being held to the front mounts by alum bolts(in my case). Figured that wasn't a good thing to happen either, I guess is my point.



    Just some more beta is all

    duck
    Last edited by Duckman; 02-09-2004 at 10:49 AM.

  25. #25
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    Quote Originally Posted by Juramentado
    Bolt-on skewers are beneficial for the front wheel only (probably why they're only avaialble with front hubs!). What this affords is an axle that cannot be displaced by the braking counter-force from the disc brake caliper. On the front fork, the placement of the disc brake caliper is such that whenever you brake, the axle experiences a force which tries to push it out of the dropout. The only thing that prevents the axle from being ejected is the clamping force on the QR, or in the case of a bolt-on, there is nowhere for the axle to go since it's effectively mounted through a hole, not a dropout.
    I think you are talking about 20mm through axles, like on a boxxer
    http://www.rockshox.com/mountain/boxxer/race.asp
    everyone else is talking about bolt-on skewers, like these
    http://oddsandendos.safeshopper.com/8/56.htm?696

  26. #26
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    Quote Originally Posted by Juramentado
    <snip>While an analysis of the QR-disc brake setup shows that disc brake caliper placement on all forks is definitely not the best in terms of the direction of force applied on the axle while braking, perhaps most people using this setup do check and tighten their QRs adequately.
    Kind of helps too if you transport your bike to the trails on a roof rack where you have to remove your front wheel each time. Kind of hard not to check it and get it tight when you just put the front wheel on. Obviously still a problem on rear and other bike racks/if you ride to the trail, check 'em = common sense.

    Now watch somebody post that I'm wearing out my front skewers taking my wheels on and off all the time... which is no different than loosening and tightening them to check them.

    And I check my bolt-on rear axle regularly too.

    Dave
    Just Passing Through: eatin' dirt & crappin' dust

  27. #27
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    Quote Originally Posted by mtbdirteater
    Kind of helps too if you transport your bike to the trails on a roof rack where you have to remove your front wheel each time. Kind of hard not to check it and get it tight when you just put the front wheel on.
    Definitely. In fact this probably accounts for why MTB riders don't have as many wheel ejection issues as the design of the brake caliper/fork mount would suggest.

    Quote Originally Posted by mtbdirteater
    Obviously still a problem on rear and other bike racks/if you ride to the trail, check 'em = common sense.
    I don't think this is an issue at all with the rear wheel, UNLESS you have horizontal dropouts. With typical rear vertical dropouts, the disc brake caliper is positioned such that braking presses the rear axle upwards into the dropout, not away from it. The axle has nowhere to go, so it's not as critical to have a very tight QR. There may be issues with a horizontal dropout though, because the force on the axle has a horizontal component and the QR will take up this force.

  28. #28
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    Quote Originally Posted by VT Mike
    I think you are talking about 20mm through axles, like on a boxxer
    http://www.rockshox.com/mountain/boxxer/race.asp
    everyone else is talking about bolt-on skewers, like these
    http://oddsandendos.safeshopper.com/8/56.htm?696
    Ah, my mistaken assumption is uncovered. Yes, I was referring to 20mm through axles. Bolt-on skewers have exactly the same issues as QRs, either front or rear.

  29. #29
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    Quote Originally Posted by Duckman
    One little tidbit more..After having a QR come loose a couple of times over as many months a year ago or so, I made some observations. The front is where the concern is. Agree 100%.
    duck
    That's very interesting. Do you know what made the QRs come loose? Do you remember what you did to them just before those rides, ie did you slap on the front wheel and forgot to check the tightness of the QR, or did you not tighten the QR enough initially, or were the "teeth" on the QR knobs worn, or any chance the lever got knocked open while riding?

  30. #30
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    Disk brake ejection

    Quote Originally Posted by Juramentado View Post
    The QR does not feel any stress at all from disc braking, since it's the axle that takes up the stress from disc braking, by being pressed into the dropout.
    Actually, this is only true if the brake caliper is in front of the fork. Normally it's behind the fork, which means that braking tends to eject the wheel from the dropout, and this is either prevented by lawyer lips on the dropout or by (over?)tightening the QR. See James Annan's work on this.

    To demonstrate this, loosen your QR, engage your front brake, grip the front wheel at the pavement contact point, and pull the front wheel aft to simulate the force that slows the bike down. If you are correct, the wheel will not come out of the dropout. Just for good measure, wiggle the wheel around a bit to simulate imperfect road surfaces and prevent a little friction from obscuring the result. If James Annan is correct, the wheel will come out of the dropout.

  31. #31
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    LOL. Juramentado hasn't logged in to MTBR since May 2004. I doubt he'll read your post.

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    Quote Originally Posted by jetboy23 View Post
    LOL. Juramentado hasn't logged in to MTBR since May 2004. I doubt he'll read your post.
    Haha, good catch. But but but someone was WRONG on the INTERNET. This shall not STAND, sir!

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    Quote Originally Posted by XCBob View Post
    I recently switched to disc brakes. The LBS told me I should turn the QR around so the handle is on the right side. I did, but I find it a lot harder to change/reinstall the wheels, especially the rear. I've seen some guys with disc brakes with the QR on the left pointed forward and up between the chainstay and seatstay. One guy had the QR pointed straight back parallel to ground. Any thoughts? Does it make any difference which side the QR handle is on ???
    really...? geeeeez, I just noticed the post date double duh...
    Attached Thumbnails Attached Thumbnails Disc brakes and quickrelease skewers ???-dsc01895.jpg  

    Disc brakes and quickrelease skewers ???-dsc01854.jpg  

    2014 Nail Trail 29...

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    attack of the ZOMBIE THREAD.

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    Quote Originally Posted by jetboy23 View Post
    LOL. Juramentado hasn't logged in to MTBR since May 2004. I doubt he'll read your post.
    Juramentado(Filipino Muslim vigilante) obviously has bigger fish to fry, than obsess over MTB technicalities...
    "This is a male-dominated forum... there will be lots of Testosterone sword-shaming here" ~ Kenfucius

  36. #36
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    QR goes in the left (non-drive) side regardless of brake type..just adjust the angle to work for you.

    Sent from my SCH-I545 using Tapatalk
    Geologist by trade...bicycle mechanic (former) by the grace of God!

    2018 Niner RKT 9 RDO - enduro AF

  37. #37
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    Zombies just don't die.

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    Quote Originally Posted by fugue137 View Post
    Actually, this is only true if the brake caliper is in front of the fork. Normally it's behind the fork, which means that braking tends to eject the wheel from the dropout, and this is either prevented by lawyer lips on the dropout or by (over?)tightening the QR. See James Annan's work on this.

    To demonstrate this, loosen your QR, engage your front brake, grip the front wheel at the pavement contact point, and pull the front wheel aft to simulate the force that slows the bike down. If you are correct, the wheel will not come out of the dropout. Just for good measure, wiggle the wheel around a bit to simulate imperfect road surfaces and prevent a little friction from obscuring the result. If James Annan is correct, the wheel will come out of the dropout.
    Front mounted disc brake: http://www.cotic.co.uk/geek/#ROADHOG_discmount

    A couple of videos that someone made a few years back.

    https://www.youtube.com/watch?v=losWKtO69q4

    https://www.youtube.com/watch?v=NIpo2Y-0rGk

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    Didn't Trek have an issue with this not that long ago?

    Essentially they were having QR levers coming lose, and a part of the QR lever that was supposed to prevent it from spinning 180 degrees wasn't working.

    So essentially when the QR lever was put rotor side, and the lever came lose, the lever came in contact and wedged itself in the rotor of the bike and locked a dude's front tire. Guy obviously does an endo from the abrupt front tire lock and gets injured looking for someone to sue.

    Guy didn't want to mention his lack of a pre-ride inspection to notice his QR was loose, but still, if it was on the other side of the fork, away from the rotor, it wouldn't have happened.

    Long story short? If you maintain your bike, the side shouldn't matter. If you don't, might as well put it on the opposite side to prevent potential issues.

  40. #40
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    Quote Originally Posted by TiGeo View Post
    QR goes in the left (non-drive) side regardless of brake type..just adjust the angle to work for you.

    Sent from my SCH-I545 using Tapatalk
    Tell that to Rockshox, who makes their forks (with 15mm thru axles) so that the cam lever goes on the drive side.

    It makes sense. Forget that I had a properly tightened but crappy QR loosen on me mid-ride when the cam was on the disc side. Who wants to be putting their fingers in the vicinity of their disc rotor to grab the cam?

    Unless it's a Fox, who has their 15mm thru axles set up so that the came is on the disc side of the fork, I put the cam on the drive side when there are disc brakes. I don't have a choice on my Rockshox fork. But on my Salsa Vaya, that's where the QR goes. Nothing has ever loosened on me mid-ride when set up that way. And it doesn't hurt anything to do it that way.

  41. #41
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    Quote Originally Posted by Harold View Post
    It makes sense. Forget that I had a properly tightened but crappy QR loosen on me mid-ride when the cam was on the disc side. Who wants to be putting their fingers in the vicinity of their disc rotor to grab the cam?
    Wish this was always the case. First thing I do on my bike, and try to get friends to do when I notice it, is to put QR levers on the drive side away from the rotor, but SRAM had other ideas. For some odd reason, SRAM X9 derailure seemed to have the cable housing go through the area where the QR lever went. I could barely get it to work if I'd angle the lever to the rear of the bike, but it was a pain. Unfortunately, had to move the lever to the brake side.

  42. #42
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    On the rear I would rather have the lever by the rotor than by the gears/chain. Diff story up front.

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    Old habits are hard to break..I have never had an issue pre- or Post-disc with QRs opening, failing on the non-drive side.

    Sent from my SCH-I545 using Tapatalk
    Geologist by trade...bicycle mechanic (former) by the grace of God!

    2018 Niner RKT 9 RDO - enduro AF

  44. #44
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    Quote Originally Posted by TiGeo View Post
    Old habits are hard to break..I have never had an issue pre- or Post-disc with QRs opening, failing on the non-drive side.

    Sent from my SCH-I545 using Tapatalk
    Like I said, my issue was compounded by a crappy qr. But you don't expect a crappy qr on a $1500 bike. Better safe than sorry. Trek had a huge skewer recall this year going back a lot of years. Based on the terms of that recall, it SHOULD apply to nearly every brand because they have all sold bikes with garbage QR skewers that would tangle in the spokes. So how many shitty unrecalled qr levers do you suppose still exist? Possibly millions. Easily.

    Flipping the skewer to the other side addresses only one problem with crappy quick releases but it is easy and doesn't cost anything.

    The resistance to this idea is silly.

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