DOT 3/4/5 brake/clutch fluid for 695

[ikillterrorists]

Well I brought my bike to the shop, the guy said that the previous person who serviced my bike put DOT 4 fluid in my brake system. On the top of the cylinder it says that you're supposed to use DOT 3 or 5 only. So the guy at the shop said that he continued to use DOT 4, since mixing the fluids would be even worse than using the wrong type. And he also says that my brakes may begin to fail eventually.

Is any of this true? Is it really bad that there is DOT 4 fluid in there instead of 3 or 5?

[Slide Panda]

Think you're reading the top wrong. They system will take DOT 3, 4 or 5.1 - not 5.

4 is usually what you're going to have in there really.

[BK_856er]

+1 to what SP said.

That shop is feeding you BS.  And how did they determine that the "previous person" used DOT 4, just by looking at the old fluid?  DOT 4 is what most of us use.

Sounds like you're good to go.

BK

[ikillterrorists]

Well I do know that these guys are BSers to begin with. And shysters.
But the top of the thing says "DOT 3 + 5". What does that mean?
In the manual it says DOT 4 so yeah guess I'm good...

[Howie]

DOT 3, 4 and 5.1 are compatible, they are poly glycol  based.  5.1 is a slightly thinner viscosity though.  The big difference is wet and dry boiling point (the higher the number, the higher the boiling point).  There are DOT 4 fluids, like ATE 200 with boiling points high enough to be 5.1.  DOT 5.1 is a thinner viscosity.

DOT5 is a whole other ball park.  It is silicone based.  When it first was released the industry thought it was compatible with poly glycol based fluids, only to find it is not in real use.  The 5.1 designation came out after this so people would not add silicone fluid to poly glycol.

 

[ikillterrorists]

Is it ok to change between the different types? Like if I used DOT 4 this time could I put in DOT 5 next time?

[ducpainter]

You don't ever want to use dot 5 unless you flush the system extremely well. Even then there are some anecdotal reports of issues.

You can switch at will from types 3,4 or 5.1

[cmejia1978]

an old guy, run a yamaha 70 something, told me that Dot 3 would be your best choice if you are not on the track, if you are you should consider DOT 4 or 5.1 like advised by others 

[scaramanga]

not sure if your bike has brembo brakes but they are INCOMPATIBLE with DOT-5 SILICONE-based brake fluids due to the seal type used (natural rubber)

[thought]

an old guy, run a yamaha 70 something, told me that Dot 3 would be your best choice if you are not on the track, if you are you should consider DOT 4 or 5.1 like advised by others 

The only differences btwn DOT 3, 4, 5.1 are the boiling points... the higher the number the higher the boiling point.  The higher number brake fluids tend to be a bit less hydroscopic so they will last a bit longer too.  And most modern bikes use DOT 4, I wouldnt use DOT 3 on a bike.

In general, for me, I use the highest numbered brake fluid I can find, the price difference tends to be negligible.

[ikillterrorists]

Yes I have Brembo brakes. Is it common knowledge that DOT 5 does work with these?? Why didn't the guy at the shop mention anything about this???

[Howie]

Obviously his knowledge is lacking.  Is he a tech?  Sales person?  Counter person?  If he is a tech find another shop.

[ikillterrorists]

Well I am going to find another shop simply because they overcharged me for everything.

[scaramanga]

found a great tech sheet here
http://www.cyclebrakes.com/html/brembo_tech_info.html

i started using ATE superblue fluid. it has a higher boiling point which resists better to the  heat especially on the clutch side.problem is that the higher the boiling point the quicker they absorb humidity resulting in corrosion of internal parts.
i change the oil in all three reservoirs 2 times per year, it doesn't take long and oil is cheap(20$/year)