Dot 5.1 Brake Fluid

[PHATR32]

hey peeps.

im after some dot 5.1 fluid but the usual stores dont stock it.

anyone got a good source?

thanks

steve

[AD4M]

perth brake parts

http://www.perthbrakeparts.com.au/index.html

cheers

Adam

[atessa]

why do you need it? good quality brake fluid, changed regularly, will be fine.

unless you intend to run bathurst...

Edited June 29, 2006 by atessa

[saf]

Hey mate, i cut and posted this from my replies on perth street bikes, save me re-typing ...

The best bang for buck fluid out there now is Motul RBF600 and Bel-Ray Super Dot4. Its 18bux or so for the small bottle (500ml) and has the highest wet and dry boiling points , equiv to SRF. Having said that SRF is mega expensive, and is best used on a dry build , ie : total rebuilt dry system.

RBF600 (311c dry , 215c wet) actually exceeds SRF (310c dry, 270c wet) by 1deg , its only weaker in wet points meaning that it needs more often changing than SRF. Wet boiling point means total saturation of alcohol based (DOT 3, 4 and 5.1) fluids with water/moisture (spec is i think 5% or near enuf to one year) where the fluids is encouraged to boil with the water in the system. Another good one is Rock Oil DOT 5.1, that works superb, but remeber like any fluid and oil, they are suited to applications, meaning you reading this may love a certain brand and i may dislike its workings, and vice versa .

Dot 4, 5 & 5.1 are all good brake fluids, the latter giving the firmer feel.

Firmer feel is nothing to do with the DOT rating system, brand and even more so , brand in a particular setup. On my CBR 929RR with Nissin brakes , i have run a very solid Motul RBF 600, nice and firm, touchy for 1 finger braking. On the CBR 1000RR with the radial Nissin master cyl, and the radial Tociko calipers, the RBF 600 on the same lines was pure junk , soft and soppy and confusing that you wernt sure if it was actually a clutch .... as it was the first time i have had to do 4 finger to the bars braking.

The majority of the MCRCWA racers are using Dot 4, and a few are using the other 2 types but mainly the Dot 5 over the 5.1. All are very close with personal preference to feel being the ultimate deciding factor.

Im not going to say what i run on the track, but any racer that runs DOT5 is either uneducated, or on a death wish. DOT5 is crap, its made for amphibious applications by the US Army / Navy (AN) as its silicone based, you wong get hygroscopic contaminination. Its boiling poisnts are commonly much lower and it is a softer fluid.

Also, swapping to DOT5 form a alcohol based fluid as from factory, as in DOT3, 4 and 5.1 family, needs a 'total rebuild' and not just a flush. It needs every aspect of the braking system stripped , cleaned and dried from any previous fluids. The reason is that silicone DOT 5 does not mix with also based fluids , and at point of separation you will get water buildup, and inconsistant braking pressure, what also later lead to corrosion and other nasties.

ROCK OIL DOT 5.1 is a fantastic fluid for eg as far as feel goes, but for eg, the Bel Ray super DOT4 actually si just as firm if not firmer, and actually pisses all over the 5.1 in wet and dry boiling points. When it comes to brake fluids, brands , rep and packaging mean absolutely squat. Sadly even spec in some cases , as in the Motul RBF 600 as in the above example, its one of the highest boiling point fluids on the market yet will work like total crap in certain applications. The best way is personal exp.

Where to get what ? If you roll into Pal & Panther in Angove st in North Perth, you can stop in and see Craig and tell him Saf sent you , (he shall do the right thing) , he has ...

Dont quote me 100% on the prices ...

Motul RBF600 ($18 500ml)

Motul DOT5.1 ($14 500ml)

Bel-Ray Super DOT4 ($16 500ml)

Silkolene DOT4 ??

Silkolene DOT4 race (like $45 buc for 300ml, but VERY VERY good)

Edited July 7, 2006 by saf

[PHATR32]

hey saf, thanx for the info. illll go down and check them out!