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Why mineral oil in hydraulic brakes, instead of silicone brake fluid?

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This question has been on my mind since I received my Sondors.  The hydraulic brakes, which work fantastically, use mineral oil.  Is there any particular reason why this was used instead of silicone brake fluid?

I have an early 2000's Harley that, before ABS was common in their bikes, uses DOT5 silicone fluid.  DOT5 foams up in ABS systems and went out of use in the mid-late 2000's as Harley adopted ABS, but it is better than DOT3 or 4 in almost every other way....it doesn't absorb water and it's not corrosive to painted surface.

I'm just curious, is all.  No issues or problems to report.

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The Easy answer is; because Tektro Engineers and Designers specified Mineral. Which might be because of the universal nature and availability of it, world wide, but that’s a guess. I do know that it won’t remove paint like some DOT fluids.
The systems on our bikes are not that demanding on the fluid’s proprieties, unlike most automotive applications. The Magura MT-5e brakes on my EBL, calls for Royal Blood, their high priced mineral oil. 
The brake system in my Grumman Light Aircraft, uses  Mil Spec fluid MIL-H-5606G. It’s a red petroleum based fluid and not the Glycol based automotive type DOT (department of transportation) fluids and no other fluid is compatible with those brakes and most systems specify a fluid and warn not to switch. In the military I was a hydraulic technician and worked on  Fixed Wing and Helicopters’ hydraulic systems including brakes. There are different milspec fluids for different aircraft types and their different systems and applications. 

This site is really informative: 





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