What brake fluid is better for my bike?

[ZinMaker]

What is better brake fluid for my bike DOT3 or DOT4? I do casual riding and some commuting on my 1981 GS750E I found this info, but still not sure what to replace my brake fluid with.


DOT3: Brake Fluid Grade - Min dry boiling pt =205degC or 401degF. Min wet
boiling pt = 140degC or 284degF. aliphatic polyether-based, can be mixed
with DOT4, characteristics will be (linearly) in between DOT3/DOt4
parameters. Cheap, most widely used, eats paint, absorbs water easily, eats
natural rubber seals.

DOT4: Brake Fluid Grade - Min dry boiling pt=230degC or 446degreesF. Min
wet boiling pt = 155degC or 311degreesF. borate ester based, can be mixed
with DOT3, characteristics will be (linearly) in between DOT3/DOT4
parameters, 50% more expensive than DOT3, eats paint, significantly
increased resistance to moisture absorption compared to DOT3 (but still
absorbs water), does not eat natural rubber seals.

[AOD]

i just put a replacement master cylinder on my bike and i went to the shelf and looked at brake fluids. the 50% cheaper DOT3 was selected for just that...its cheap. if your brake system is functioning properly, then water should stay out of it. since the systems are designed for DOT3 they dont have any 'natural rubber' seals that can get damaged.

i'm sure you're fine with DOT3, if you want to spend the extra go with DOT4, but i dont think you're going to see any difference.

~Adam

[Anonymous]

I use el cheapo Walmart brake fluid DOT3. Have been using it for years, and nothing's ever gone wrong with my brakes, front or rear. As long as the fluid is clean and the motorcycle is used and maintained regularly, DOT 3 or 4 won't matter one bit in any street or touring applications.

Nick

[redliner1973]

The only real difference in DOT 3 or 4 is the 'wet boiling point'. If you do alot of real hard braking for sustained periods, like going fast down a mountain road, or track racing then go with a DOT4. if you just do normal riding, DOT 3. The higher the 'boiling point', the less teh brakes will fade under a severe use. I use DOT 3 in mine, without any problems at all. :twisted:

[Anonymous]

brake fluid will absorb water, its like 2% a year, just flush yearly and is ok.