BRAKE FLUID

andrew s · Post by **andrew s** » Tue Jan 04, 2005 5:00 pm

Can any of you recommend a make of brake fluid, or are all the makes the same. I know I need DOT Four, but is there any particular brand better. Bye the way it is for my YZF 750 and not my 'S'.

Cheers,
Andrew

Gromit · Post by **Gromit** » Tue Jan 04, 2005 5:27 pm

I think brake fluid's pretty much brake fluid tbh - just get a reputable make's stuff and job's a good'un. I remember that someone once said don't mix DOT3 with DOT5 though.

Oh...and always use fresh stuff as it's hygroscopic.

madman · Post by **madman** » Tue Jan 04, 2005 5:32 pm

Brake fliud is synthetic and DOT 4 standard will mean that they are all just about the same. One problem with brake fluid is that it is hygroscopic, that means that it absorbs water. Any water will boil when in the hot area near the brake and cause the brakes to become spongey, it may also cause corrosion.
The way round this is to use DOT 5. DOT 5 is silicone based and is not hygroscopic. It will feel no different to DOT 4 and is totally compatable. If you choose to change DOT 4 regularly then there is no real advantage to using the more expensive DOT 5.

Boxadog 2000 · Post by **Boxadog 2000** » Tue Jan 04, 2005 6:33 pm

I thought that you could not use Dot 5 in a system that had used Dot 4

madman · Post by **madman** » Tue Jan 04, 2005 9:48 pm

Yes you can. You can even change to DOT5 by bleeding through the DOT4, I have done iy loads of times on past bikes with no ill effects - my old K100 that I had a few years ago went from 12000 miles to 85000 miles with no problem after changing with this method.

boxerpan · Post by **boxerpan** » Wed Jan 05, 2005 7:54 am

Boxadog 2000 wrote:I thought that you could not use Dot 5 in a system that had used Dot 4

I understood the same Bob, thought it was the seals that were suitable for dot4 OR dot5 ? Anyone on here have a definative answer?

carlk · Post by **carlk** » Wed Jan 05, 2005 8:50 am

Whilst I am not an authority on the matter everything I have ever read says the two fluids are incompatible the mixing of the two will result in coagulation and possible failure of the system due to blockages.
the seals on a dot 5 (silicone) system are different to those on a dot 4.

My '99 buell M2 cyclone had a dot 5 system

However dot 5 should not be confused with dot 5.1 which is a better version of dot 4 and is incompatible with dot 5

confused

>>>>> we should be

Gromit · Post by **Gromit** » Wed Jan 05, 2005 9:09 am

carlk wrote:
confused >>>>> we should be

Ditto

RiceBurner · Post by **RiceBurner** » Wed Jan 05, 2005 10:48 am

madman wrote:Yes you can. You can even change to DOT5 by bleeding through the DOT4, I have done iy loads of times on past bikes with no ill effects - my old K100 that I had a few years ago went from 12000 miles to 85000 miles with no problem after changing with this method.

Can you confirm that you're using DOT5 or DOT5.1????

madman · Post by **madman** » Wed Jan 05, 2005 2:37 pm

Not anymore I'm afraid. I sold the K100 ages ago and have gone back to my youth with the R1100S!

madman · Post by **madman** » Wed Jan 05, 2005 2:44 pm

Warning. I have mixed as in my previous post but have just run a search on DOT 5 at http://www.belray.com/consumer/productp ... t5sil.html, and they quote that the two should not be mixed! Well it worked OK for me but I promise that I won't do it on the precious S. I have all the time in the world to change brake fluid these days anyway - its nice to retire in my 40s.

oyster · Post by **oyster** » Wed Jan 05, 2005 7:13 pm

I too have the opinion that Dot 5 should only be introduced to a virgin system; as heard from the racing stables, but have never questioned why they cant be mixed. Unless the bike is on the track, Dot 4 will cope with the work. Track bikes cook the fluid, so it (Dot 4)

should be changed as often as you can afford. Much worse is the fade on ordinary (EBC!!!) pads which leave a hot glaze that wont work. I am also unaware of specific seals required, I did not think that was an issue.

mdouglas · Post by **mdouglas** » Wed Jan 05, 2005 7:39 pm

Pop down to Halfords and get some Castrol Super DOT4 "Response" fluid. Has many of the benefits of DOT5 but confirmed as DOT4 compatible.

http://www.castrol.com/castrol/productd ... Id=7000403

boxerpan · Post by **boxerpan** » Wed Jan 05, 2005 9:09 pm

mdouglas wrote:Pop down to Halfords and get some Castrol Super DOT4 "Response" fluid. Has many of the benefits of DOT5 but confirmed as DOT4 compatible.

http://www.castrol.com/castrol/productd ... Id=7000403

Sounds like a marketing ploy to rob more money off the punter to me

Gromit · Post by **Gromit** » Wed Jan 05, 2005 9:11 pm

mdouglas wrote:Pop down to Halfords and get some Castrol Super DOT4 "Response" fluid. Has many of the benefits of DOT5 but confirmed as DOT4 compatible.

http://www.castrol.com/castrol/productd ... Id=7000403

Yup - must be good, I use it in the MZ

It does most excellent stoppies...as long as there's nothing too heavy in the top box

www.boxertrix.com

BRAKE FLUID

BRAKE FLUID

Dot 4 - 5?