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anrajala 09-13-2006 04:57 AM

Re: Brake Fluid Does Matter
Wayne, many came to Idaho where I am from, but that was very long time ago. Those newcomers could be perhaps from Mexico? Finland and Mexico are very similar, we both have plenty of snow apart from Mexico.

- cruiz-euro

anrajala 09-13-2006 05:09 AM

Re: Brake Fluid Does Matter
They are scientific facts. As Gandhi said: "Screw the freeking idiots". Lemme ask you a question. If you have brake fluid that corrodes the brake system from the inside in a long run, in a bike that you want to keep for many years, what does that make you?

- cruiz-euro

RRRIDER 09-15-2006 05:24 AM

Re: Brake Fluid Does Matter
I've never heard that DOT 4 fluid corrodes the insides, but have heard DOT 5 does. Yes DOT 5 does have a higher boiling point, but I doubt you'll ever reach those temps on a Cruiser unless your brakes are extremely under par or you decide to take it to the track (no, not the dragstip). Going from stop light to stop light will not over heat your brakes or break down the fluid immediately(over time, yes) DOT 4 & 5.1 are safe for modern brake systems, although I'm not sure about Harleys since the technology is older (except for the V-rod maybe). If Harleys are made to use DOT 5, then put it in. I personally wouldn't mix the 3&5 for the same reasons stated by another member, lowering the boiling point. I wouldn't use DOT 5 by itself in my bike after hearing it corrodes. Do what you want to do to your bikes.

nolaandy 09-22-2006 08:12 AM

Don't mix them, and don't use silicon
Statement: Polyglycol brake fluids corrode the braking system

Polyglycol brake fluids (like DOT 3 and 4) are hygroscopic. When they absorb water they tend to destroy the rubber bits in the brake system. Solution: Bleed once a year. Empty the master, refill with clean fluid, and gravity bleed each caliper until you get nice, clean fluid out. I bleed mine at least once every six months on all my vehicles. I have a 1996 Chevy Astro with 94,000 miles on it. I changed out all the brake parts, including flex hoses, for an extended road trip in 1994. Disassembly showed that only the wheel cylinders looked a bit sad. Other than that I had replaced no parts but shoes and pads.

Statement: Silicon fluids corrode the brake system.

Since silicon based fluids do not absorb water, condensed water can pool in droplets and corrode aluminum and non-stainless parts of the braking system.

"Mixing" isn't wise since they really don't mix. Sort of like oil and water, you can get them together but neither will be happy.

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