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  1. #1
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    DOT fluid vs. mineral oil

    What are the differences in the brakes that use DOT vs. mineral oil?

    Is it the type of seals or are there actual engineering differences in the way they are designed?

    And is there any reason to prefer one over the other?

  2. #2
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    its mostly in the seals that the differences lie, DOT type systems use EPDM rubber, while mineral oil ( commonly known as hydraulic fluid) use nitrile (NBR).

    the main limiter is that the rubber types cannot be interchanged as the incompatible fluid will cause the seals to swell, initially causing sticking, and as the rubber weakens, they fail.

    there will be other differences as to how the systems are designed, but they are likely to be very subtle relating to how the fluids behave when heated and pressurized.

  3. #3
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    A lot of people prefer mineral oil over DOT because it is a non-toxic oil that won't harm your skin or your bike's finish if it spills or leaks. DOT is nasty stuff (a mixture of different chemicals) but as long as you wash your hands soon after messing with it there is no harm done. Personally, I use DOT simply because I like Hope brakes. I've spilled DOT on my bike's finish before but immediately wiped it up with a rag and never had any damage to the paint.

  4. #4
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    What is the break down of which brands use what?

    Mineral Oil
    Shimano
    magura?

    Dot

    Hayes
    Avid

  5. #5
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    You can add Formula to the DOT list.

  6. #6
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    Magura and Shimano are the only companies I know of that use mineral oil.

    The rest use DOT brake fluid.

  7. #7
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    all the tektro hydraulics I have seen use mineral oil. ( actually an ok brake too at that pricepoint)

  8. #8
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    Well then

    Mineral Oil
    Shimano
    Magura
    Tektro

    DOT
    Hayes
    Avid
    Formula

  9. #9
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    + Gatorbrake to mineral oil

  10. #10
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    It could be mainly design issues, but I like DOT brakes (Formulas, Avid and Hope) over mineral oil brakes (Shimano, Magura). More feel and modulation. DOT fluid doesn't bother me. Just wear gloves or wash your hands.

    I have Formula Ones on my bikes. Best brakes out there.

  11. #11
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    Another difference is that mineral oil does not absorb water, while DOT does. This would probably never matter unless you went a really, really long time without changing your fluid AND the seals became compromised, but it is a differnce in the properties of the two fluids.

    This is why it's essential to keep DOT containers sealed very tightly if you plan to store them for any length of time.

    -Pete
    I can barely get my mouth around it.

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    I prefer shimano brakes as most shops do and as a bonus I do not have to worry about croaking from liver failure as DOT fluid absorbed by the skin over a prolonged period is toxic, fact of life is if you do your own wrenching you will have to deal with DOT fluid ruining your bike paint and your health.XT/XTR the best and most reliable.....flat fact.

  13. #13
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    Quote Originally Posted by HUZZA
    I prefer shimano brakes as most shops do and as a bonus I do not have to worry about croaking from liver failure as DOT fluid absorbed by the skin over a prolonged period is toxic, fact of life is if you do your own wrenching you will have to deal with DOT fluid ruining your bike paint and your health.XT/XTR the best and most reliable.....flat fact.
    Most shops do? please.

    You would have to absorb quite a bit of DOT fluid to induce liver failure. Face it, anyone that gets brake fluid on their hands or spills it on a regular basis is a poor mechanic. I spent years as an auto mechanic bleeding brakes and never once got it on my hands, clothes, or customer's paint.

    And XTR are not the best or most reliable. They are nice brakes tho (I have owned both).
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    Quote Originally Posted by TLL
    Most shops do? please.

    You would have to absorb quite a bit of DOT fluid to induce liver failure. Face it, anyone that gets brake fluid on their hands or spills it on a regular basis is a poor mechanic. I spent years as an auto mechanic bleeding brakes and never once got it on my hands, clothes, or customer's paint.

    And XTR are not the best or most reliable. They are nice brakes tho (I have owned both).
    yea...ok, I work with many end stage cancer patients and quite often they wonder how they got to this point, what is generally suspected are toxins and/or genetic pre disposition.....mechanics and such are prone to cancer...hope that is not the case with you, mineral oil is rather benign.I meant liver cancer or cancer in general on earlier post yep most shops I know of ...shimano is very dependable even down to the LX level...just my opinion though, you cut through all the marketing crap and shimano is a good choice or high end magura.

  15. #15
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    Quote Originally Posted by HUZZA
    I prefer shimano brakes as most shops do and as a bonus I do not have to worry about croaking from liver failure as DOT fluid absorbed by the skin over a prolonged period is toxic, fact of life is if you do your own wrenching you will have to deal with DOT fluid ruining your bike paint and your health.XT/XTR the best and most reliable.....flat fact.
    i heard if your body took in enough mineral oil it would make you poop.


    Not to mention that at only 15 degrees higher than the dot 5.1 boiling point, mineral oil can spontaneously combust. Imagine that... you're screaming down a hill, grab the brakes, and the whole brake system catches fire!

    mineral oil doesn't absorb water like DOT fluid does, so if enough water collects in your hydraulics, it could boil over and leave you with no brakes at all!

    The risk doesn't end when you get off the hill,mineral oil can cause pneumonia, cramps, vomiting, and it may cause dermatitis People downplay the danger of mineral oil compared to DOT fluid, but DOT fluid can be rendered inert with water, while there's no easy solution to the mineral oil threat.

    Really.... both fluids are pretty harmless. Get a little DOT fluid on you and it makes your skin dry out a little, just don't bathe or drink the stuff. Get the brakes you like the feel of most.
    Last edited by scottzg; 09-04-2008 at 11:29 PM.
    affect befect cefect defect effect fect

  16. #16
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    Mineral oil with a different melting point is commonly sold in most shops on the planet with a label: "Vaseline"

    No, it will not kill you and yet it will indeed make you poop if you eat enough of it.

    MSDS sheet is correct, but you will not be inhaling the mineral oil in order to get pneumonia, you will also not be drinking it down in large quantities - if you do you may indeed get cramps just before a bout of explosive diarrhea, and everything and anything can cause dermatitis.

    DOT is dangerous, depending on who you ask. Here is the MSDS for the popular ATE DOT 4. Spilling DOT on your skin will not kill you, drinking it may, and apparently no authority claims that it causes cancer.

    Lastly, for fire you need air.

    V.

  17. #17
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    Most bikes aren't painted...

    Quote Originally Posted by HUZZA
    I prefer shimano brakes as most shops do and as a bonus I do not have to worry about croaking from liver failure as DOT fluid absorbed by the skin over a prolonged period is toxic, fact of life is if you do your own wrenching you will have to deal with DOT fluid ruining your bike paint and your health.XT/XTR the best and most reliable.....flat fact.
    Most bikes are powder coated (or anodized). Waaay more chemical resistant. Some high end bikes from small handmade type builders are actually painted. Paint is much more candy-like in finish, but chips easily. Powder coat is really durable.

    The health issue isn't really a problem unless you work on them day in and day out without gloves. I don't always wear gloves, but I always wear goggles in case something squirts.

    BTW, my 4 pot XTs felt great, but dragged all the time. Pistons would not retract reliably. That isn't going to stop me from trying another set in the future. I'm just saying Shimanos aren't 100% reliable. I've had bad luck with Maguras, but good luck with two sets of Hopes.

    How bout some punctuation?

  18. #18
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    Quote Originally Posted by pimpbot
    Most bikes are powder coated (or anodized). Waaay more chemical resistant. Some high end bikes from small handmade type builders are actually painted. Paint is much more candy-like in finish, but chips easily. Powder coat is really durable.
    False.

    Paint doesn't have to be more candy-like. Powder coat can be candy too.

    Many paints are a one-stage. Most bikes are painted, some are powder coated. Fewer are anodized.

    My XTR m965 brakes and groupset worked like crap. It howled and had very little power. My 755s work just fine. I took the time to face my mounts and center it properly and they don't rub. My 965 caliper paired to an 08 XT caliper works alright. My old LX brakes worked okay. My old Deores worked fine too.

  19. #19
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    Perhaps I should just edit my previous post, but then no one will find it. What do you people think? And yes I prefer mineral oil simply b/c it is almost completely benign. I just wanted to know what my options were. I have used Avid J5, Hayes (of the older variety which worked very reliably for ages), shimano xtr m965 (which worked perfectly for me), and xt 765 which worked for about two years without bleeding, just changing pads, but just recently have started to have some issues so I probably need to try bleeding them. (My fork was leaking a bit of oil on the rotor though so I wasn't sure where the problem was coming from for sure).

    Updated:

    Mineral Oil
    Shimano
    Magura
    Tektro
    Gatorbrake

    DOT
    Hayes
    Avid
    Formula
    Hope

  20. #20
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    Quote Originally Posted by HUZZA
    yea...ok, I work with many end stage cancer patients and quite often they wonder how they got to this point, what is generally suspected are toxins and/or genetic pre disposition.....mechanics and such are prone to cancer...hope that is not the case with you, mineral oil is rather benign.I meant liver cancer or cancer in general on earlier post yep most shops I know of ...shimano is very dependable even down to the LX level...just my opinion though, you cut through all the marketing crap and shimano is a good choice or high end magura.
    I knew you were referrring to liver cancer.

    The thing is, the exact etiology or certain types of cancers is unknown . . is it environmental factors, genetic predisposition, old age, or ??? And I am not sure that mechanics are more prone to certain types of cancer, though I do not have any stats in front of me---perhaps you do have stats and could share, as I'm actually interested in the subject.

    Again, Shimano does make a great brake, no argument there.
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  21. #21
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    Quote Originally Posted by vmajor
    Mineral oil with a different melting point is commonly sold in most shops on the planet with a label: "Vaseline"

    No, it will not kill you and yet it will indeed make you poop if you eat enough of it.

    MSDS sheet is correct, but you will not be inhaling the mineral oil in order to get pneumonia, you will also not be drinking it down in large quantities - if you do you may indeed get cramps just before a bout of explosive diarrhea, and everything and anything can cause dermatitis.

    DOT is dangerous, depending on who you ask. Here is the MSDS for the popular ATE DOT 4. Spilling DOT on your skin will not kill you, drinking it may, and apparently no authority claims that it causes cancer.

    Lastly, for fire you need air.

    V.
    It freaks me out to think about how little toxin skin absorbtion it would take to give one cancer, if I can easily avoid a toxic substance..if their are options as this is the case then thats great.Corporations have much to lose by actively stating the toxic effects of their products, many people simply ignore the danger, cancer is a horrible price to pay..be careful? If I were racing downhill events the DOT may be worth the risk,,mineral oil has notgiven me any problems for trail riding.

  22. #22
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    all dots are seriously more toxic to the environment than minerals!
    and i really think this is more imp than fine differences that they may (or may not have). we should all push through our demand even more companies having mineral oil fluids i think!

  23. #23
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    Oh yeah, try using this so called "mineral oil" instead of DOT in your car, or other high temp apps.

    Then of course, there's the issue of what mineral oil really is. People think they can simply dump mineral oil into the sewer or drink it and it's great. Think again.

    When handled properly, even the most toxic items pose little to no risk. Stop being such a baby.

  24. #24
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    surely it's not ok to just dump mineral into the washer, but surely it's less toxic than dot! my opinion is that the differences between them (in bikes at least) does not outweigh the dots higher degree of toxicity. i'd be ok with a little decrease (which i doubt personally, maguras are excellent brakes) in performance over no toxic dot fluids.

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    I still don't believe you're making your point. I said if handled properly, DOT isn't a problem. Hell, I've been getting it on my hands since I was a kid bleeding brakes and clutches on cars.

  26. #26
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    Quote Originally Posted by Jerk_Chicken
    I still don't believe you're making your point. I said if handled properly, DOT isn't a problem.
    i don't doubt that, i doubt that they're handled properly by everyone involved! given that doubt of mine, it's better not to handle properly mineral oils than dots!
    i'm not saying that the world is at stake, just that i prefer less toxic substances used. given my belief that the difference in performance is not so big, in bike brakes at least.

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    The problem is they are labeled with proper care and usage instructions. Why do I have to compromise using the superior performing product when people are just not smart enough to use them right?

    Even if you're trying to be "green", this thinking can go way too far. I remember the propylene glycol engine coolants that really didn't transfer heat well. Do you?

    If you're worried about the environment, make sure your brakes don't leak, repair them when a leak is detected, make sure they are disposed of properly, wear gloves, if you must, and that's it.

    It's really not like mineral oils are non-toxic, once again. Try pouring some in a plant on your window and see what happens.

  28. #28
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    well i said what i believe, there's no point arguing any longer. you are of course entitled to your beliefs, and i'm sure you handle (as most people) the fluids properly.
    hell,i'm not gonna judge a person from using dot or mineral!!!
    as for the analogies to the automotive industry, i won't argue with any of that, just that i'm not sure if the bike brakes' performance is to the same extent compromised. i don't know,maybe it is. but i find maguras excellent performers. it's not like i want less reliable brakes on my bike!!!nobody wants. if you feel so, you absolutely are entitled to ask for the best you think exist! but it's not that straightforward as to say that all mineral fluid brakes are less performing or reliable. i don't think so at least

  29. #29
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    If you do some research, I think you'll find that most mineral oil used in brake systems has adequate heat performance for the intended application. In fact, Magura Royal Blood mineral oil for brakes has a higher boiling point than most DOT fluid. Also, most DOT absorbs water readily, which quickly lowers the boiling point (aka "wet" boiling point).

    Regarding toxicity, I don't know for sure, but I seriously doubt most mineral oil used in brake systems is the same stuff you can buy at the drug store. Sure, maybe it will work as a substitute for the manufacturer recommended fluid, but I'd bet the manufacturer fluid has plenty of additives in it to improve the performance which also makes the fluid more toxic in some way.

    I prefer mineral oil mostly because I have had FAR fewer troubles with mineral oil based brakes than DOT. All the DOT brakesets I've owned so far end up with sticky pistons eventually, even with regular fluid changes. I don't know if it is due to the water absorption or something else, but I haven't had those troubles with Magura Martas.

  30. #30
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    Quote Originally Posted by B R H
    If you do some research, I think you'll find that most mineral oil used in brake systems has adequate heat performance for the intended application. In fact, Magura Royal Blood mineral oil for brakes has a higher boiling point than most DOT fluid. Also, most DOT absorbs water readily, which quickly lowers the boiling point (aka "wet" boiling point).
    That's why I use easily available high quality, low moisture absorption fluids that have high boiling points. They are available inexpensively, such as Valvoline Synthetic. They are longer lasting.

    In regard to the higher BP of Magura fluid, the issue remains that using metallic pads is not recommended because the fluid will overheat.

    Regarding toxicity, I don't know for sure, but I seriously doubt most mineral oil used in brake systems is the same stuff you can buy at the drug store. Sure, maybe it will work as a substitute for the manufacturer recommended fluid, but I'd bet the manufacturer fluid has plenty of additives in it to improve the performance which also makes the fluid more toxic in some way.
    Correct. People are all up in arms about DOT and Mineral and being "green". I can show the side of a can of Pentosin or any other industrial use "mineral" oil and you will question whether you would think words too long to pronounce are safe for the environment. As someone with a chemistry degree, I know exactly what these additives are when I read down the list.
    I prefer mineral oil mostly because I have had FAR fewer troubles with mineral oil based brakes than DOT. All the DOT brakesets I've owned so far end up with sticky pistons eventually, even with regular fluid changes. I don't know if it is due to the water absorption or something else, but I haven't had those troubles with Magura Martas.
    Can be up for debate. There are plenty that get sticky pistons with the mineral based systems. Thus far, in about 5-6 years of hydraulic disc usage, the only pistons I had that were a bit sticky were new brakes, simply because they need to break in. Depending on the conditions, it's a good idea to do an oil change every 12-18 months, depending if the fluid is LMA or not. It's not a true comparison if you're declaring this only based on your experience with one brake. I have had dozens pass by me in some form, and the stats on sticky pistons actually go in the favor of the DOT side being more reliable in that sense, since the Shimano calipers started having those problems.

  31. #31
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    The boiling point for Magura fluid is 383 degrees F. This is probably exceeds most DOT fluids in practice (i.e., wet).

    Fluid overheating really is more of a system design issue than a problem with any particular fluid used. The Martas in particular are definitely a minimalist design using a very low volume of fluid - too low in my opinion.

    I agree that the "green" arguments are ridiculous.

    I should have said seized pistons rather than simply sticky. I've had a set of Hope Minis, Formula B4SL, & Hayes HFX all suffer from seized pistons. All used DOT fluid. The fluid was changed at least annually on the Minis & B4s, but never on the Hayes. I used Golden Spectro DOT 4. I was able to revive the Minis & HFX, but the B4s are still stuck (require total disassembly but will probably not be salvageable). I have 3 sets of Martas, all 3 years old that still function like new despite never taking the time to full change the fluid, although it was refreshed thru bleeds.

    I think sticky pistons might be a function of piston & seal design, but I also wonder what role the fluid type plays. Is DOT more volatile (in an evaporative sense) than mineral oil brake fluid? Which has more lubricity?

  32. #32
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    In DOT brake systems with no magnesium components I use AP Racing 600 fluid. Dry BP 572F. Wet BP 410F.

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    BTW I used mineral oil from a drug store in my brakes without ill effects for over a year before exchanging it. It was what I had at the time and I wanted to test them immediately. It worked fine and I never had a problem with it. And it was dirt cheap of course.



    PS. I have a chemistry degree as well jerk chicken

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    Ok, ok, I couldn't help but chime in. I am a mechanical engineer working for an oil company and I service and sell industrial process fluids and lubricants – and have certifications related to such (CMFS/STLE/HazWoper/etc.) I teach operators, conduct safety training and sell thousands of gallons of hydraulic oils, DOT oils, ester based, synthetics, alkaline cleaners, soluble MWF, etc. every day. I'm also working in and around this stuff constantly. NO ONE in the mountain biking community has anything to worry about with these products relating to the normal maintenance and service of their bikes. I promise you, I know what i'm talking about!!

    First, there are two types of exposure to foreign chemicals relating to your body – 1) Acute: a short, severe exposure and 2) Chronic: a long, moderate exposure over an extended period of time. (Such as a ‘chronic smoker’ or ‘chronic drinker’) This thread is discussing people who, with the exception of bike shop techs, see this stuff MAYBE once a year and your exposure doesn’t even qualify as acute, given the amounts involved the ‘route of entry (see below)’. You have nothing to worry about. Even if you work in a bike shop and your only job is to work on hydraulic systems you still have nothing to worry about.

    Second, routes of entry. There are several routes of entry: ingestion, absorption, inhalation, injection, etc. Being waterproof, your skin is a pretty good barrier so absorption (which the route of entry we are discussing here) offers the least threat. The worst you could get from bathing in these oils is maybe some dermatitis but even that would only happen to a few.

    The bottom line is that we are talking about tiny amounts of non-hazardous fluid getting on your skin. I’d worry more about French fries, drinking too much or the Chinese putting melamine in your kids milk. The guy farther up the thread talking about cancer is a nut job. You have more chemicals under your kitchen sink that can kill you quickly than anywhere else. Ever spill bleach on yourself while doing the laundry? THAT stuff is bad.

    RIDE ON! BW

  35. #35
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    Excellent. Appreciate the accurate information.
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  36. #36
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    I guess this isn't too far off topic. What's the difference between Dot 3 and Dot 4?

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    Quote Originally Posted by beedubs
    Ok, ok, I couldn't help but chime in. I am a mechanical engineer working for an oil company and I service and sell industrial process fluids and lubricants – and have certifications related to such (CMFS/STLE/HazWoper/etc.) I teach operators, conduct safety training and sell thousands of gallons of hydraulic oils, DOT oils, ester based, synthetics, alkaline cleaners, soluble MWF, etc. every day. I'm also working in and around this stuff constantly. NO ONE in the mountain biking community has anything to worry about with these products relating to the normal maintenance and service of their bikes. I promise you, I know what i'm talking about!!

    First, there are two types of exposure to foreign chemicals relating to your body – 1) Acute: a short, severe exposure and 2) Chronic: a long, moderate exposure over an extended period of time. (Such as a ‘chronic smoker’ or ‘chronic drinker’) This thread is discussing people who, with the exception of bike shop techs, see this stuff MAYBE once a year and your exposure doesn’t even qualify as acute, given the amounts involved the ‘route of entry (see below)’. You have nothing to worry about. Even if you work in a bike shop and your only job is to work on hydraulic systems you still have nothing to worry about.

    Second, routes of entry. There are several routes of entry: ingestion, absorption, inhalation, injection, etc. Being waterproof, your skin is a pretty good barrier so absorption (which the route of entry we are discussing here) offers the least threat. The worst you could get from bathing in these oils is maybe some dermatitis but even that would only happen to a few.

    The bottom line is that we are talking about tiny amounts of non-hazardous fluid getting on your skin. I’d worry more about French fries, drinking too much or the Chinese putting melamine in your kids milk. The guy farther up the thread talking about cancer is a nut job. You have more chemicals under your kitchen sink that can kill you quickly than anywhere else. Ever spill bleach on yourself while doing the laundry? THAT stuff is bad.

    RIDE ON! BW
    Yes indeed! I am going to trust an oil company wanker to tell me the truth about toxins.....damn! now I can rest easy.I am sure NO one is covering up how humans acquire cancer, that would upset the company stockholders.....right sport?.I can think of numerous drugs applied to the skin that are quite effective...so Einstein your logic is lame.The point is if given a choice I am going to use a less toxic item if feasible and your skewed logic means nothing to me considering your place of employment try and focus now OK champ? shimano hydraulic brake fluid is less caustic the DOT fluid....flat fact and I challenge you to prove otherwise
    Last edited by HUZZA; 10-11-2008 at 10:14 AM.

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    Actually I kind of agree with Beedubs, but at the same time. Why expose oneself to something that is toxic when it is unnecessary. One might as well limit the exposure. It isn't like this is DMSO and just going to ooze thru your skin.

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    Quote Originally Posted by ric426
    I guess this isn't too far off topic. What's the difference between Dot 3 and Dot 4?
    In short: boiling point. BP is higher for DOT 4 than DOT 3 and higher again for DOT 5 and DOT 5.1. DOT 3, 4, and 5.1 are all similar in that they are glycol based and DOT 5 is silicon based and as such a whole different kind of animal. This wiki page gives a short overview, and this lists the minimal boiling points the fluids have to comply to.

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    Quote Originally Posted by sxotty
    Actually I kind of agree with Beedubs, but at the same time. Why expose oneself to something that is toxic when it is unnecessary. One might as well limit the exposure. It isn't like this is DMSO and just going to ooze thru your skin.
    yes I am quite sure he is a fine represenitive of the petrochemical industry however he is not involved in healthcare and my point is as you said why take a chance with DOT fluid that is caustic and toxic? I trust oil companys as far as I can spit

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    Call me silly, but I prefer DOT because it is readily available and inexpensive. On several occasions I have needed to bleed brakes quickly after work. On those occasions, I just stopped by the gas station quick and easy.

  42. #42
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    try having to make an emergency repair and bleed while away.

  43. #43
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    Quote Originally Posted by Jerk_Chicken
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    try having to make an emergency repair and bleed while away.
    If you cannot find mineral oil (also available at auto parts stores) you are not looking very hard at all. It is readily available pretty much everywhere.

  44. #44
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    I have always looked for mineral oil at bike shops. Where (on a national basis) is mineral oil for brakes found besides a bike shop?

  45. #45
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    Quote Originally Posted by Cable0guy
    It could be mainly design issues, but I like DOT brakes (Formulas, Avid and Hope) over mineral oil brakes (Shimano, Magura). More feel and modulation. DOT fluid doesn't bother me. Just wear gloves or wash your hands.

    I have Formula Ones on my bikes. Best brakes out there.
    More "feel and modulation"? You're joking, right?

    Both mineral oil and DOT fluid are incompressible (like virtually all fluids), and I'd imagine that the hoses for brakes are all equally non-compliant (i.e. they resist distension equally well). That means they're going to perform the same, at least hydrodynamically. There's just not enough of a difference from model to model with regard to fluid flow through the hoses.

    Any difference you notice in "feel and modulation" would almost certainly come from the brake levers or the calipers themselves.

  46. #46
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    Mineral oil increases our dependency on foreign oil. If you use mineral oil in your brake lines the terrorists win.

  47. #47
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    is there a difference between DOT 4 oil and other DOT number oils?

    is there a "best" oil for Avid Brakes?
    2008 Transition Dirtbag w/Totem

  48. #48
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    DOT 5 is silicone based and is not compatible.

    DOT 5.1 is glycol based. DOT 3 and 4 are also glycol based. They can be mixed. Typically DOT 5.1 has a higher boiling point than DOT 4 and DOT 4 has one higher than DOT 3. But there are some DOT 4 fluids like Motul RBF 600 that outperform some DOT 5.1 fluids.

    Avid has started shipping their brakes with DOT 5.1. DOT 4 is what they used to ship with.

  49. #49
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    Quote Originally Posted by paps
    all dots are seriously more toxic to the environment than minerals!
    and i really think this is more imp than fine differences that they may (or may not have). we should all push through our demand even more companies having mineral oil fluids i think!
    Picking up on the environmental piece, how are either of these supposed to be disposed of. Our landfill has an annual 'bring in your toxic crap and we will take care of it' day, but what do (or what should) shops do with brake fluid (and all the other stuff they process).

    Oh and to follow the tradition of elaborating my credentials to establish my authority, I have been hugging trees for over three decades, and have 3 advanced degrees in asking stupid questions.

  50. #50
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    Only mountain bikers freak out so bad over brake fluid. In the search, there are several discussions about this, including classifications of how something may be an irritant.

    Please, I've been working with brake fluid since I was a kid. These people make you think it will turn you into a CHUD. Just use proper care and even if you get it on your hands or paint, nothing will happen. Wash it off.

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