Brake Fluids

[munter]

Hi Guys,
As I have some track time coming up i'm planning on upgrading the brakes on my MX5.

Could someone update my brain on brake fluids (Is dot4 what I want?). And where I can order what I want online.

(I would ask the MX5 owners club forum but it's gone down...dow!)

Cheers!

[richardb.jones]

Hi - yes DOT4 should be fine but double check with your handbook. I suggest a decent racing DOT4 such as Motul RBF600 etc (much higher boiling point than normal fluid).

Don't get DOT5 it's not compatible at all and DOT 5.1 although compatible, I would avoid unless absolutely necessary - stick with what the brake system was designed for IMO.

I hope this helps ...

PS - RBF600 available from Opieoils (Sponsor)...

[birdthom]

Agreed on the Motul RBF600, but why avoid DoT 5.1 out of interest?

[munter]

Well I just checked my (Haynes equivalent) manual and it says DOT 3 or DOT4 but to avoid DOT 5.1 as well.

What it doesn't tell me is how much I need?...Will 1 litre be enough?

[GreenV8S]

DOT 5.1 is a higher (more stringent) standard than DOT4 so I would have thought that DOT 5.1 was preferable.

As somebody said earlier, DOT5 is the stuff to be avoided, it's completely incompatible with the other types and not suitable for road use.

[falcemob]

What's the problem with DOT5.1 then?

[GreenV8S]

falcemob said:

What's the problem with DOT5.1 then?

Nothing, as far as I know.

[munter]

GreenV8S said:

falcemob said:

What's the problem with DOT5.1 then?

Nothing, as far as I know.

I figure the handbook I have is basing it's advise on the car being for road/fast road use and 5.1 being overkill.

[willr]

See

www.stoptech.com/tech_info/wp_brakefluid_1a.shtml

[anonymous-user]

I've got Maxxis Ultimates, Motul RBF 600 and Goodridge hoses all around on my MX5 now. Absolutely superb. Coped with lapping the 'Ring at the weekend with no problems. Ultimates and hoses from Phil at P5, Motul from Opie Oils. 1 litre will be fine - I flushed through a litre of Halfords cheap dot 4 first (on Phil's recommendation) but then found I couldn't tell when I'd bled it all out and replaced with the Motul. Hmmm. Wonder if you can get a dye to put in it...

When doing the brakes, bleed the clutch fluid at the same time. The slave cylinder is accessible from the offside wheel arch.

[munter]

Hi Guys,
Well I ordered 1 Litre of the Motul racing DOT 4 from Opie oils. Whats turned up is Silkolene Pro Race Break Fluid DOT4.

Now I had a scoot around on their site and the stuff I have appears to be move expensive so not complaining on that front. It's not what was reccommended so does anybody have any experiance of this Silkolene fluid?

Cheers

[taffyracer]

I personally only use Castrol SRF or Mintex Black, you can either use the cheaper stuff like the Motul and change it more frequently or use the better gear and change it less frequently, horses for courses on costs, but SRF and Mintex Black are about the best you can get

[anonymous-user]

The important bit is the dry and wet boiling points. If the Silkolene is as good then no worries. IIRC Motul and Silkolene are actually the same company so it may well be exactly the same fluid.

Castrol SRF may be good stuff but at over £50 a litre, you could do a lot of changes on the Motul or similar for a difference of around 50 degrees C in wet boiling point (216 for the Motul vs 270 for the SRF) and the same dry boiling point. Just change it more often and you won't have to worry about the wet boiling point.

[Munter]

Having looked around it looks like the spec is almost exactly the same. So I'm going to use it and see how I get on.

Cheers guys

[Graham]

I used to run Castrol SRF but I've had Better Results with AP600, which has an added benift of being cheaper

[GVK]

I wasted 2 litres of SRF once chasing a decent pedal (mc was fooked at the finish) that hurt!

I've used Motul RBF600 for the last couple of years,great stuff and good value.