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  1. #1
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    I don't like DOT fluid.

    It stems from a Toyota pick-up I had in high school. I don't remember exactly what happened but there was a leak in the brake system and the brake fluid stripped a lot of the paint off of the engine compartment. So that's why I've stuck with Magura or Shimano disc brakes over the years and haven't had any problems with these two manufacturers.

    Now I'm reading all these good reviews on the Formula stuff and am thinking of trying them out. So how bad is DOT brake fluid? If I get this stuff on my fancy new frame or carbon goodies, is it going to strip the paint as soon as it comes in contact or can I wash it off in a reasonable amount of time and be fine?

    Also, these will be going on a raw Turner RFX...any issues with getting this stuff on raw aluminum.

  2. #2
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    You will have plenty of time to wash off with water. DOT is not paint remover that strips almost ASAP. Have done many brake bleeds, hose replacement & crash repairs where the brake line riped off on Moto's without a problem.
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  3. #3
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    DOT=No big deal.

    Don't listen to the children that come here with little practical experience with DOT fluid that act like it's Uranium. The moment they recommend a brake based on not using DOT because it strips paint, you will be able to separate who actually knows what they're talking about vs. who buys into the marketing campaigns.

    At this point, those folks are likely to say you can drink mineral oil from your brakes if you're thirsty.

    Both fluids work and that's it. Don't decide based on this sky is falling fear.

  4. #4
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    Quote Originally Posted by Jerk_Chicken

    At this point, those folks are likely to say you can drink mineral oil from your brakes if you're thirsty.
    ...although it might give you the runs.

    Off topic, why do people think that you never have to bleed mineral oil brakes? Sure, dot fluid is hygroscopic and brakes get spongy eventually, but this seems far preferable to brakes that let the water sit in the lines and expand when the brakes get hot and pump out the lever and reduce braking effectiveness. I don't have any real first hand experience with mineral oil brakes, so maybe in practice it doesnt happen?
    .

  5. #5
    Meh.
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    As mentioned DOT fluid will not instantly eat everything in it's path. You have plenty of time to wipe it off and deactivate it with water. Though if you let it sit... it might do some harm. Your carbon bars should be clearcoated.

    People say you don't have to bleed mineral oil brakes because it is no hygroscopic. The boiling point does not lower. Since it is a sealed system... water should not be able to enter. If water doesn't get in... there is no problem. But in real life... it CAN happen.

  6. #6
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    I have to say, that if properly handled, both fluids should be fine. I tend to prefer the Mineral oil brakes a lot though.
    Have been on Shimano brakes for a long time, have some really old Magura brakes (HS22 etc.) which are almost 13 years old, heavy use in rain/alps ... they are on the first bleed and fine, no problems at all, good heat resistance.

    And I have 2 pairs of 2 year old Avid Juicys and both are in need of a bleeding, one actually showed some problems with heat and boiling dot. So, not the DOT is the problem, but the handling. If it is kept in a bottle and it is not airtight or whatever, or not properly degased when bleeding, it can cause trouble.
    I guess both systems have advantages and problems, I prefer Mineral oil because you donīt need to worry about it. Never had boiling problems etc. Hand friendly and no problem for Magnesium Carbon and Alloy parts.

    In the end, brakes should REALLY only be handled and being worked on by trained / experienced people. And they should be able to handle either fluid.


    A hint: IF you prefer Mineral oil, stay with Shimanos, they are affordable, reliable and have a perfect finish.



    Greetings Znarf

  7. #7
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    Quote Originally Posted by scottzg
    Sure, dot fluid is hygroscopic and brakes get spongy eventually, but this seems far preferable to brakes that let the water sit in the lines and expand when the brakes get hot and pump out the lever and reduce braking effectiveness. I don't have any real first hand experience with mineral oil brakes, so maybe in practice it doesnt happen?
    Quote Originally Posted by XSL_WiLL
    People say you don't have to bleed mineral oil brakes because it is no hygroscopic. The boiling point does not lower. Since it is a sealed system... water should not be able to enter. If water doesn't get in... there is no problem. But in real life... it CAN happen.
    In the past 11 years that has never once happened to me. I have never had water in the lines, and i'm not sure how it would get in. In real life, if the system isn't sealed to such an extent that water might be able to enter, the oil is going to come out first, when you squeeze the lever.

    There's great DOT brakes and there's great mineral oil brakes. Be glad we have so much choice.

  8. #8
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    Quote Originally Posted by XSL_WiLL
    As mentioned DOT fluid will not instantly eat everything in it's path. You have plenty of time to wipe it off and deactivate it with water. Though if you let it sit... it might do some harm. Your carbon bars should be clearcoated.

    People say you don't have to bleed mineral oil brakes because it is no hygroscopic. The boiling point does not lower. Since it is a sealed system... water should not be able to enter. If water doesn't get in... there is no problem. But in real life... it CAN happen.
    Over time, with the pistons going in and out, air does accumulate and get past seals enough for either system to need a bleed. That's why one would bleed a mineral system as well. Also, particles produced from normal wear need to be flushed out. Whether there's hygrogospicopy to the fluid or not, if there's air coupled with temp changes, minute amounts of water are introduced into the fluid. In the case of DOT, the fluid disperses it within. In the case of mineral oil, it floats as "aqueous micelles" for lack of a better term.

  9. #9
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    I had a big spill of dot fluid all over my black and gold hopes, I cleaned it up with water.
    Question, what's the best product to use on the black lever body to get rid of ALL traces of dot fluid after a bleed? Is it alcohol or will that maybe damage the finish as well...

  10. #10
    Track Junkie
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    Lots of water will get rid of spilled DOT fluid. No other chemicals necessary.

    I prefer to use Castrol LMA in my braking systems for my bikes and (race) cars. It's cheap, works well, and is readily available at most auto parts stores.

    http://www.castrol.com/castrol/secti...tentId=7024043
    I get paid to ride shotgun.

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