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  1. #1
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    Interesting observation. Roundagon vs Cleansweep G2

    I had my bike on a trail that went 35 miles with a 7,000 foot drop and got to really try the brakes out for the first time.

    I have BB7s front and rear with a 203mm roundagon up front and a 185mm cleansweep in the rear. I have to admit I was wrong on my theory.

    First test, I got up to 30mph and braked somewhat gently and steadily until stopped on a 13% grade. I stopped in a marked off distance every time. My observations were the cleensweep although smaller didn't get as hot as the roundagon but it was close. I was stopping by dragging the brakes the whole time. These stops were at the limit of being able to touch them without burning myself instantly.


    Then I tried going faster but applying the brakes, letting off, applying again, letting off, until I was stopped. I did the same number of applications for each brake and this is where the real difference was. The cleansweep was pretty warm. The roundagon burned me pretty bad.

    I've always assumed that since the roundagon had more mass, it would take longer to heat up. This may still be true but the cleansweep cools so much quicker, in the real world it's going to run cooler under any normal condition.

    Regardless, they stopped me at 250lbs over and over from 30+mph without fail.

  2. #2
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    Not really a fair/valid test. The rear brake doesn't do as much "work" as the front because of weight shift on the bike as you're going downhill, and that your weight shifts forward when you're stopping anyway.

  3. #3
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    Quote Originally Posted by Monte
    Not really a fair/valid test. The rear brake doesn't do as much "work" as the front because of weight shift on the bike as you're going downhill, and that your weight shifts forward when you're stopping anyway.

    Re-read the test. I stopped in the same distance every time. Weight and traction makes no difference because I never approached the limits of traction. Each brake does the same work stopping the same weight from the same speed in the same distance.

  4. #4
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    My opinion: too many variables in the test. Front vs rear brake, rotors of different sizes. But that's beside the point. I think if you accounted for those and tested a roundagon vs a clean sweep of the same size under the same conditions, you would get the same result. My understanding is that clean sweep rotors come with hydraulic systems precisely because they're designed to cool faster and not overheat the brake fluid; mechanicals do not suffer that problem, hence being able to keep costs down with a less intricately machined rotor.
    Quote Originally Posted by JonathanGennick View Post
    I am a poser. But forums.poser.com doesn't seem to exist, so I come here instead.

  5. #5
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    Quote Originally Posted by Slow Eddie
    My opinion: too many variables in the test. Front vs rear brake, rotors of different sizes. But that's beside the point. I think if you accounted for those and tested a roundagon vs a clean sweep of the same size under the same conditions, you would get the same result. My understanding is that clean sweep rotors come with hydraulic systems precisely because they're designed to cool faster and not overheat the brake fluid; mechanicals do not suffer that problem, hence being able to keep costs down with a less intricately machined rotor.
    Don't forget that Avid also sells the BB7 for about half the price of their cheapest hydraulic brake (Juicy 3). Even if the Cleansweep did help the BB7 perform better as well, Avid probably doesn't want to raise the price of the BB7 more to include the better rotor. People will only pay so much for a mechanical disc brake

    Actually, didn't the BB7 used to come with Cleansweep rotors a few years ago? EDIT: yep, they did

  6. #6
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    You need ABS on your brakes.

  7. #7
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    Quote Originally Posted by Slow Eddie
    My opinion: too many variables in the test. Front vs rear brake, rotors of different sizes. But that's beside the point. I think if you accounted for those and tested a roundagon vs a clean sweep of the same size under the same conditions, you would get the same result. My understanding is that clean sweep rotors come with hydraulic systems precisely because they're designed to cool faster and not overheat the brake fluid; mechanicals do not suffer that problem, hence being able to keep costs down with a less intricately machined rotor.

    Don't forget, I was testing a smaller cleansweep against a larger roundagon and the cleansweep still stayed cooler. I think that's pretty conclusive being that the cleansweep was at a disadvantage but came out on top.

    I wish you guys would get off the front vs rear. I was stopping in the same measured distance for both brakes. Same g-force. Front vs rear does not matter in this case.

  8. #8
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    Most scientific test ever.

    JK it really isn't.
    Bike good, work bad.

  9. #9
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    Quote Originally Posted by Clutchman83
    Most scientific test ever.

    JK it really isn't.
    ...but come on, we need posts like this so we could laugh at someone

  10. #10
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    This experiment is very scientific. Factors that make it very scientific and controlled are:
    1. Using very reliable gauge to measure temperature - hand
    2. Test sample is very comparable - 203mm vs 185mm
    3. Using precision equipment to apply same force - hand again - abeit different sides
    4. Test very similar conditions - both mount on a bike - only one in front where front wheel has practically unlimited traction
    5. Test bias - test was NOT blinded so tester conducted test w/ prejudices

    See? Very scientific experiment. Might I mention that there was an experiment by Sir Robert Bennett Bean that found 100% correspondence that black people's brains were smaller than white people's. Only when Franklin Mall in the US tried to duplicate results but using a blinded study found 0% correspondence whatsoever.

  11. #11
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    "1. Using very reliable gauge to measure temperature - hand"

    Level 1: Meh
    Level 2: Ow.
    Level 3: Oooow!
    Level 4: Owwa!!
    Level 5: !*%?!
    Level 6: Aaargh!!!

    Looks perfectly scientific to me.

    What use is a philosopher who doesn't hurt anybody's feelings? -
    Diogenes


  12. #12
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    Quote Originally Posted by Clutchman83
    Most scientific test ever.

    JK it really isn't.
    No ****. I must've forgotten my heat sensor for my mountain bike ride.

    The plain and simple of it is the stopping distances were measured and kept consistant for every test. So was the speed. It was nohwere near the limit of traction even for the rear so front/rear bias plays no role. The only thing lacking are acutal temp measurements. There was enough difference in temp to feel it with my fingers which is all the proof I need.

    Really, I know it makes you feel good to try and pick others apart but besides your useless comment, explain to me why this is not valid.

  13. #13
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    Come on guys, just go through some of the OP's post history if you want to have some real laughs at boneheaded observations and theories.

  14. #14
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    Quote Originally Posted by vk45de
    This experiment is very scientific. Factors that make it very scientific and controlled are:
    1. Using very reliable gauge to measure temperature - hand
    2. Test sample is very comparable - 203mm vs 185mm
    3. Using precision equipment to apply same force - hand again - abeit different sides
    4. Test very similar conditions - both mount on a bike - only one in front where front wheel has practically unlimited traction
    5. Test bias - test was NOT blinded so tester conducted test w/ prejudices

    See? Very scientific experiment. Might I mention that there was an experiment by Sir Robert Bennett Bean that found 100% correspondence that black people's brains were smaller than white people's. Only when Franklin Mall in the US tried to duplicate results but using a blinded study found 0% correspondence whatsoever.
    Are you people too stupid to read my entire post?

    1. There was enough difference to feel by hand. When one burns you and the other will allow you to leave your hand on for a few seconds, that's a difference.

    2. Once again I'll repeat myself. The 185 (cleansweep) was at a size disadvantage yet still ran cooler so this is even more evidence to support the superiority of the cleansweeps.

    3. What does force matter when I'm applying just the right amount to stop in a pre-measured distance from the exact same speed?

    4. Once again, repeating myself, the measured distance vs the speed resulted in a slow steady stop. Traction of either tire played no role. I stopped just as slowly with the front as I did with the rear.

    5. Predjudices? I had no idea what was going to happen and I really didn't care. What I wanted was my front and rear rotors to look the same so I needed to figure out whether to buy another roundagon or another cleansweep.

    Seriously, everyone in this thread is so caught up in their superiority complex that they end up looking like the stupid ones.

  15. #15
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    Quote Originally Posted by Jerk_Chicken
    Come on guys, just go through some of the OP's post history if you want to have some real laughs at boneheaded observations and theories.
    Ah the peanut gallery is alive and well. Last I remember I tore you a new *******.

  16. #16
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    i find that since my fingers are calloused from bike maintenance, i use my tongue to test the "heat" of a brake.

    i burned myself on the front rotor after a ride, but the back didn't burn as bad.

    clearly meaning the front one was less efficient.

    i tried to run my finger over the rotor while i was riding once, too, but then i went over the front bars for some reason. clearly my brakes are to blame.

  17. #17
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    Quote Originally Posted by BuickGN
    Seriously, everyone in this thread is so caught up in their superiority complex that they end up looking like the stupid ones.
    HA!

    This one's gonna be fun.
    Bike good, work bad.

  18. #18
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    Quote Originally Posted by BuickGN
    Ah the peanut gallery is alive and well. Last I remember I tore you a new *******.
    Must have been the Pabst Blue Ribbon talking.



    There's always the NASCAR mullet as well:



    Anyhow, just like your old posts. You resort to calling everyone else a-holes, when your post history kind of shows either a bit of trolling, or an unhealthy obsession, coupled with lack of understanding, of the operation of brakes.

  19. #19
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    Quote Originally Posted by eat_dirt
    i find that since my fingers are calloused from bike maintenance, i use my tongue to test the "heat" of a brake.

    i burned myself on the front rotor after a ride, but the back didn't burn as bad.

    clearly meaning the front one was less efficient.

    i tried to run my finger over the rotor while i was riding once, too, but then i went over the front bars for some reason. clearly my brakes are to blame.
    That's very intelligent. You can't intelligently pick apart anything so you make smart ass comments. Another one that's too stupid to realize he's stupid.

  20. #20
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    Quote Originally Posted by Jerk_Chicken
    Must have been the Pabst Blue Ribbon talking.



    There's always the NASCAR mullet as well:



    Anyhow, just like your old posts. You resort to calling everyone else a-holes, when your post history kind of shows either a bit of trolling, or an unhealthy obsession, coupled with lack of understanding, of the operation of brakes.
    As usual, nothing to contribute. You follow me around like a little ***** looking for attention. One day you'll get off my nuts but I suppose negative attention is better than no attention for someone like yourself.

  21. #21
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    I won't take "you're stupid" from the likes of you.
    Quote Originally Posted by BuickGN
    3. What does force matter when I'm applying just the right amount to stop in a pre-measured distance from the exact same speed?
    Exemplary case - yes it does. Did you know that if you apply more force towards the beginning of the stop, your brakes will be cooler when you do stop?

  22. #22
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    "Another one that's too stupid to realize he's stupid."

    That should be another one who's too stupid...

    What use is a philosopher who doesn't hurt anybody's feelings? -
    Diogenes


  23. #23
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    Quote Originally Posted by BuickGN
    That's very intelligent. You can't intelligently pick apart anything so you make smart ass comments. Another one that's too stupid to realize he's stupid.
    i just find your methodology hilarious.

    even if you took an IR temperature gun out there with you, i'd still laugh at you for comparing a front bb7 rotor with a back one, and of different size and specs for that matter--not even considering if you had the brakes adjusted properly.

    given the fact that i use a tiny rear bb7 brake rotor because anything bigger just tends to lock up the rear wheel (not a good thing), the cable slack, mechanical disadvantage, pad adjustment, pad wear, etc. are so random that if your funny little test were to mean anything, you'd have to try it under the same conditions with two similar FRONT rotors and use some kind of scientific (big word for book learnin) methodology to prove your ramblings.

    i use clean sweeps because i THINK they bite harder compared to roundagons.

    i have no proof for that.

    and neither do you in your assertions.

  24. #24
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    Quote Originally Posted by eat_dirt
    i just find your methodology hilarious.

    even if you took an IR temperature gun out there with you, i'd still laugh at you for comparing a front bb7 rotor with a back one, and of different size and specs for that matter--not even considering if you had the brakes adjusted properly.

    given the fact that i use a tiny rear bb7 brake rotor because anything bigger just tends to lock up the rear wheel (not a good thing), the cable slack, mechanical disadvantage, pad adjustment, pad wear, etc. are so random that if your funny little test were to mean anything, you'd have to try it under the same conditions with two similar FRONT rotors and use some kind of scientific (big word for book learnin) methodology to prove your ramblings.

    i use clean sweeps because i THINK they bite harder compared to roundagons.

    i have no proof for that.

    and neither do you in your assertions.
    But everything you cite doesn't matter. Explain to me why it matters if it's on the front or the rear when I'm no where close to the traction limits. I set a distance and speed that could be easily stopped with the rear brake with no locking.

    If I said the smaller rear is inferior because it gets hotter than the larger front, that would be dumb. But in fact the smaller rotor stayed cooler, that means something.

    And once again, get off this front vs rear thing. It makes no difference on these super easy stops. It only matters when the front braking exceeds the rear traction limits which did not happen in this case.

  25. #25
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    Quote Originally Posted by vk45de
    I won't take "you're stupid" from the likes of you.

    Exemplary case - yes it does. Did you know that if you apply more force towards the beginning of the stop, your brakes will be cooler when you do stop?
    Yes, and that's the first good argument in this thread. Thank you for that.

    I did my best to keep the stops linear. We're talking 10+ stops here, not just one and every time I had the same results.

    I understand this is not the most scientific test but I got the same results over and over again.

  26. #26
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    the smaller rotor is staying "cooler" because of cable tension, pad adjustment, your own "subjective" opinion of what it is cool and hot, the fact that it's not working as hard, the interaction of the different design with the pads, checking one rotor before the other, heat dissipation... too many variables. you might as well be comparing the heat of the cassette to the front rotor.

  27. #27
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    Quote Originally Posted by BuickGN
    But everything you cite doesn't matter. Explain to me why it matters if it's on the front or the rear when I'm no where close to the traction limits. I set a distance and speed that could be easily stopped with the rear brake with no locking.

    If I said the smaller rear is inferior because it gets hotter than the larger front, that would be dumb. But in fact the smaller rotor stayed cooler, that means something.

    And once again, get off this front vs rear thing. It makes no difference on these super easy stops. It only matters when the front braking exceeds the rear traction limits which did not happen in this case.
    The front brake is still doing more work even before you reach the limit of traction, because of weight transfer

  28. #28
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    Quote Originally Posted by boomn
    The front brake is still doing more work even before you reach the limit of traction, because of weight transfer
    No it's not. I can't believe this many people don't understand this. You could have 1,000lbs on the front and 100lbs on the rear and as long as you're not stopping harder with the front than the rear is capable of at it's traction limits you will not generate any extra heat.

    Total weight is what matters here, not weight on each tire.

  29. #29
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    Quote Originally Posted by BuickGN
    If I said the smaller rear is inferior because it gets hotter than the larger front, that would be dumb. But in fact the smaller rotor stayed cooler, that means something.

    And once again, get off this front vs rear thing. It makes no difference on these super easy stops. It only matters when the front braking exceeds the rear traction limits which did not happen in this case.
    You really need to evaluate your thought processes regarding this statement. You are disregarding tons of variables. If you want to be taken seriously you will realize you are wrong and your test is completely irrefutably un-scientific and dumb as hell.

    Are you 12 years old? Or did you drop out before science class in high school?

    It's got to be one or the other.
    Bike good, work bad.

  30. #30
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    Quote Originally Posted by BuickGN
    No it's not. I can't believe this many people don't understand this. You could have 1,000lbs on the front and 100lbs on the rear and as long as you're not stopping harder with the front than the rear is capable of at it's traction limits you will not generate any extra heat.

    Total weight is what matters here, not weight on each tire.
    WRONG! SO WRONG IT'S NOT EVEN FUNNY! STOP POSTING IMMEDIATELY!!!!
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  31. #31
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    Quote Originally Posted by Clutchman83
    WRONG! SO WRONG IT'S NOT EVEN FUNNY! STOP POSTING IMMEDIATELY!!!!

    Elaborate, please. So you're saying that at the same braking rate at the same speed, the rear will always run cooler? That weight that transfers to the front magically disappears and goes away? You've found a way to defy physics. That's awesome.

  32. #32
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    Quote Originally Posted by eat_dirt
    the smaller rotor is staying "cooler" because of cable tension, pad adjustment, your own "subjective" opinion of what it is cool and hot, the fact that it's not working as hard, the interaction of the different design with the pads, checking one rotor before the other, heat dissipation... too many variables. you might as well be comparing the heat of the cassette to the front rotor.

    That's one very large ASSumption.

    They're both working equally as hard.

    Same pad material.

    Subjective, maybe, but one burns instantly while the other does not, that's pretty conclusive.

  33. #33
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    Quote Originally Posted by BuickGN
    That's one very large ASSumption.

    They're both working equally as hard.

    Same pad material.

    Subjective, maybe, but one burns instantly while the other does not, that's pretty conclusive.
    you clearly don't understand how your bike works. or elementary jr. high physics.

  34. #34
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    Quote Originally Posted by eat_dirt
    you clearly don't understand how your bike works. or elementary jr. high physics.

    A reading comprehension class wouldn't hurt you.

    I was not touching one brake and then the other. I was doing a run, touching the rotor and then doing the exact same run and touching the other rotor. Not one and then the other so that one has time to cool before the other.

  35. #35
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    Quote Originally Posted by BuickGN
    A reading comprehension class wouldn't hurt you.

    I was not touching one brake and then the other. I was doing a run, touching the rotor and then doing the exact same run and touching the other rotor. Not one and then the other so that one has time to cool before the other.

    Wait.

    Are you trying to say that you're testing one brake at a time on these runs?

    Not that it changes much of what has been said to this point, but if that's the case, I don't think that was made very clear in the first post. If so, I think you are justified in your argument that the front or rear brake works equally hard, when it is the only brake applied. If both brakes are being used simultaneously, the general consensus withing the cycling (and moto/auto) community is that the front brakes "do more" than the rear brakes when coming to a complete stop.
    Quote Originally Posted by JonathanGennick View Post
    I am a poser. But forums.poser.com doesn't seem to exist, so I come here instead.

  36. #36
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    Quote Originally Posted by BuickGN
    Elaborate, please. So you're saying that at the same braking rate at the same speed, the rear will always run cooler? That weight that transfers to the front magically disappears and goes away? You've found a way to defy physics. That's awesome.
    There is no way you can quantitatively say this with the variables you are working with. I'll spell it out for you.

    1 - Your fingers are not an accurate device with which to measure force. Others have already told you this but you keep choosing to ignore it.

    2 - You have different size rotors which exact different torques on the wheel even if you were using the exact same force (which you are not, I guarantee you) you would need to be able to take this into consideration. Others have already told you this but you keep choosing to ignore it. This doesn't even matter because you are using your fingers as force sensors AND temp sensors, which is totally stupid.

    3 - You aren't taking into consideration you're pad composition or level of use. You cannot be certain the pads are at the same level of wear, or even if they are of the same type. Organic or metallic? New or not? This doesn't even matter because you are using your fingers as force sensors AND temp sensors, which is totally stupid.

    4 - Cable and housing condition, are the cables new or stretched out? Is the rear cable stretching more than the front because it's longer? This doesn't even matter because you are using your fingers as force sensors AND temp sensors, which is totally stupid.

    5 - Brake lever setting. Are you certain the front and rear are set the same? The avid levers have an adjuster for the leverage it exacts on the caliper so you can set it to be stronger or weaker. This doesn't even matter because you are using your fingers as force sensors AND temp sensors, which is totally stupid.

    5 - Brake caliper alignment. Are you certain both front and rear brakes are aligned properly, not dragging the calipers, not off center/bending/warping the rotor when you apply the brakes. This doesn't even matter because you are using your fingers as force sensors AND temp sensors, which is totally stupid.

    There's more, but I'm wasting too much time typing this.
    Bike good, work bad.

  37. #37
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    Quote Originally Posted by Slow Eddie
    Wait.

    Are you trying to say that you're testing one brake at a time on these runs?

    Not that it changes much of what has been said to this point, but if that's the case, I don't think that was made very clear in the first post. If so, I think you are justified in your argument that the front or rear brake works equally hard, when it is the only brake applied. If both brakes are being used simultaneously, the general consensus withing the cycling (and moto/auto) community is that the front brakes "do more" than the rear brakes when coming to a complete stop.
    I should've made that more clear. Now I understand how I sounded like an idiot.

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    Fantastic thread. Hope we can do it again, fellas.

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    Quote Originally Posted by eat_dirt
    the smaller rotor is staying "cooler" because of cable tension, pad adjustment, your own "subjective" opinion of what it is cool and hot, the fact that it's not working as hard, the interaction of the different design with the pads, checking one rotor before the other, heat dissipation... too many variables. you might as well be comparing the heat of the cassette to the front rotor.
    This makes sense if you thought I was using both brakes at the same time. I should've been more clear in the beginning.

  40. #40
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    Blood, guts, carnage!

    Damn!...I looked at this thread...noticed JC was driving the locomotive...and sure enough in a very short time....
    Attached Images Attached Images

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    Dude, you even got mullets. What else could you ask for?

    ...and hell, I knew enough to let the loco steer itself. Even went food shopping, and sure as hell, it went straight into a neighboring town.


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    It's interesting observation indeed. What is most interesting that peoples keeps arguing even after clarifying on the test condition (one brake at a time), meaning they are just arguing for the arguing sake

    I'm lazy to look up the history of the OP to see if other posts carry proper argumentation, but this thread great example of how to read internet responses. Whole page of garbage with single proper counterargument

    But hey, all good. Nice entertainment for few minutes (Yes, I'm really bored)
    I used to run tubes like you are, but then I got thorn in my wheel.

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    Am I arguing now?!!

    Quote Originally Posted by Stalk
    It's interesting observation indeed. What is most interesting that peoples keeps arguing even after clarifying on the test condition (one brake at a time), meaning they are just arguing for the arguing sake
    Actually, the thread almost instantly died when that was finally made clear about 5 posts ago

  44. #44
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    Frictional force is the coefficient of friction times the normal force. Normal force can be determined by mass, gravity, and the angle. If there is less weight over the rear wheel, there is less normal force, therefore less frictional force. This means that less force is required to exceed the frictional force. In other words... it takes less power to break traction. Weight is also transferred forward while braking... note the weight transfer in a car. In a straight line, slam on the brakes. The front end will dive down. Or... Romp on the gas... the rear end will squat and the front end will rise.

    Suspension design and setup (both front and rear) will also affect the ability to maintain contact with the ground.

    I run a 140mm rotor in the rear, and it still stays much cooler than my 160 front, or even a 203mm fromt.

    This is hardly a scientific test by any means.

    Put the rotor on a brake dyno. Have the dyno spin at a specific speed and with a specific amount of torque. Apply the same amount of pressure for the same amount of time for each rotor. Measure the temperature.

    Though you may have stopped in the same distance, or even used the same number of applications of brake... the force applied to the rotor can vary. The front rotor being larger will have a larger moment arm. So less force is probably applied over a longer duration.

  45. #45
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    No you don't ... or do you? (I'm confused )

    But why no one is discussing if having cooler rotor is actually good or bad (OP assumes it's good)?
    Since stopping is only achieved by braking and initial kinetic energy the same, braking should transform it to the same amount of heat. If one rotor is cooler its either cooling faster (that would be good thing) or it's just taking less heat and more heat goes into pads/caliper. For mechanicals it may not be an issue, but for hydro I would like to heat rotor instead of caliper for less chances of brake fade.
    So, since rotors made from same material and cooler rotor actually smaller (less area) so it can't cool-off any faster (true term would be dissipate large amount of energy over same period of time) , so it's indeed causing more heat transferred to the pads/calipers. So roundagon seems a winner for hydraulics.

    I warned that I'm bored
    I used to run tubes like you are, but then I got thorn in my wheel.

  46. #46
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    Or it could be that some energy is converted to energy other than heat... like sound.

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    Quote Originally Posted by XSL_WiLL

    I run a 140mm rotor in the rear, and it still stays much cooler than my 160 front, or even a 203mm fromt..
    Of course it will because you *can* apply much more force to the front brake. I was stopping in the same distance at the same speed with either rotor so that point is null and void.


    Quote Originally Posted by XSL_WiLL
    Though you may have stopped in the same distance, or even used the same number of applications of brake... the force applied to the rotor can vary. The front rotor being larger will have a larger moment arm. So less force is probably applied over a longer duration.
    You're right but that's not the topic. What I was interested in is the temps in a real life braking situation, not using the exact same clamping force on each rotor which would result in different braking force since they are different sizes. Forget using the exact same psi from each caliper, what matters is stopping with exactly the same g-force over the same distance at the same speed and then comparing temps.

  48. #48
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    Actually the caliper can apply no more force regardless of whether it is front or rear. But doesn't your statement also make your claim null and void? Given that you are running a smaller rotor in the rear.

    It's simply not a fair comparison when using two different sized rotors on different ends of the bike. With the larger rotor, the pads don't have to bite as hard. This means less pressure needs to be applied to the rotor.

    My proposed experiment was to use one of each rotor in the same size.

  49. #49
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    Quote Originally Posted by XSL_WiLL
    Or it could be that some energy is converted to energy other than heat... like sound.
    That would be interesting Given OP can burn finger with energy off one rotor, that's would contribute to a lot of sound. "Dune" fans rejoice, sonic gun is closer to reality then we thought.
    I used to run tubes like you are, but then I got thorn in my wheel.

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    Quote Originally Posted by Stalk
    No you don't ... or do you? (I'm confused )

    But why no one is discussing if having cooler rotor is actually good or bad (OP assumes it's good)?
    Since stopping is only achieved by braking and initial kinetic energy the same, braking should transform it to the same amount of heat. If one rotor is cooler its either cooling faster (that would be good thing) or it's just taking less heat and more heat goes into pads/caliper. For mechanicals it may not be an issue, but for hydro I would like to heat rotor instead of caliper for less chances of brake fade.
    So, since rotors made from same material and cooler rotor actually smaller (less area) so it can't cool-off any faster (true term would be dissipate large amount of energy over same period of time) , so it's indeed causing more heat transferred to the pads/calipers. So roundagon seems a winner for hydraulics.

    I warned that I'm bored
    LOL. Now you're just arguing for argument's sake. A cool rotor is always a good thing. Even if a large portion of heat is going into the pads, a cooler rotor can keep pad temps under control.

    The cooler rotor does not mean it's transferring more heat into the pads. It can mean it's cooling more during it's rotation where it's not between the pads which is what I think is happening. It is an interesting point you bring up though.

    Of course the mechanicals can suffer from pad fade just as easily as hydros. It may be a little harder to boil the fluid though.

    My original theory was that the roundagons with their extra mass would take longer to heat up and I figured heat dissipation between the two would be a wash. It looks like the additional surface area with the cutouts in the cleansweep do make a difference.

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