Brake fluid recommendations please

Going to junk the rubber brake hose (looks like the original), with a Goodridge Shadow Gold one (gold hose , black fittings - looks better than it sounds).  They didn't have any at the show, but have said that if I send mine in, they'll do one for £20 inc. P&P.

Does anyone have a brake fluid recommendation?

When I changed my hoses on my GS650GT I used Cobra lines (http://www.cobraperformance.co.uk/), fantastic service and a good price. I will only use EBC fluid (http://www.sportsbikeshop.co.uk/motorcycle_parts/content_prod/184343), but then I will now only buy EBC pads (Double H Sintered). To be honest any dot4 should be fine, do not mix grades though ie. I would think your bike has standard dot4 in it so do not add dot5 but I think you can mix dot4 and dot5.1

v-twin wrote:

 To be honest any dot4 should be fine,

 Brake fluids pretty much the same no matter what make.

From the internet:


The Department of Transportation (DOT) classifies brake fluids to defined specifications.
These specifications relate to their boiling points and chemical composition, both of which are important. All currently available brake fluids are covered by one of the following specifications; DOT3, DOT4, DOT5 and DOT5.1.
The laws of thermo-dynamics dictate that the energy from motion is turned into heat through friction. A braking system only works efficiently if the fluid remains incompressible. If the brake fluid boils, it turns to gas, which is compressible and the braking system becomes “spongy” or in extreme cases fails completely.
A brake system is not perfectly sealed and moisture can get into the system and be absorbed by the fluid. The effect is to reduce the boiling point of the fluid, which reduces the efficiency of the braking system, as described above.

The DOT specifies two reference tests for brake fluids.
* Dry boiling point - the boiling point of fresh fluid
* Wet boiling point –the boiling point once the fluid has absorbed moisture (representing brake fluid after time spent in a real situation).

There are two main types of brake fluids:
* DOT 3, DOT 4, Super DOT4* and DOT 5.1 which are based on poly glycol compounds.
* DOT 5, which are based on Silicone.
Note the two types of fluid are not compatible and must not be mixed in a braking system.

SILICONE BRAKE FLUID (DOT 5)
Silicone based DOT 5 was originally introduced to give higher temperature performance over glycol DOT 4. Silicone fluid also has other advantages, it does not damage paintwork and it does not absorb water. However, silicone fluid is a poor lubricant and does not lubricate ABS pumps as well as PAG fluids. It is also more compressible than PAG fluids, which can result in a sluggish or spongy pedal. It therefore requires special design considerations in braking systems. Further, because it does not absorb water, any water remains as globules, which can pool in low spots in the system and cause corrosion. This water can vaporise when heated under heavy braking giving a disastrous effect on braking efficiency.
DOT5 fluids are not recommended for motor sport applications.

POLY GLYCOL BRAKE FLUIDS (DOT 3, 4 AND 5.1)
Glycol based DOT 4 fluid is the current mainstream brake fluid, and you will see that the specification is considerably better than DOT 3 which it replaces.
DOT 5.1 has higher specification still and is for fast road and occasional track day use. It has a similar spec to DOT4 for the boiling point (>260) but is a lot lower viscosity @-40C typically 900 centistokes (compared to 1500 - 1800 centistokes for DOT 4 and super DOT 4).

Listed in the table below, are the minimum dry/wet boiling point specifications for each DOT level.
BOILING POINT:
DOT 3 - 205°C (dry) / 140°C (wet)
DOT 4 - 230°C (dry) / 155°C (wet)
DOT 5 (silicone) - 260°C (dry) / 185°C (wet)
DOT 5.1 (PAG) - 260°C (dry) / 185°C (wet)
Super Dot4 * - 300°C (dry) / 195°C (wet) (racing brake fluid)
* Super DOT4: The main difference between DOT 4 and Super DOT 4 is the dry boiling point. Normal Dot4 is >260C whilst Super DOT 4 is more like >310C


So now you know.

Can't get much more comprehensive than that - thanks all.

Halfords do one called "Vodka" - sounds promising !!!!

I know it's cold but don't drink it could lead to the worst hangover you've  ever had

Thanks for the info Andrew, I will read that all when I ain't so pissed.

Hi Dave you been to Halfords.

Yeah I drunk their vodka, I was so shocked when I saw they started selling booze.           

I have never tried DOT5.1 because I think it is not necesary on a Custom Bike and have never tried Super DOT4 because don't know if it is a good upgrade

I usually used CASTROL BRAKE FLUID DOT 4 500 mL, instead of only 250mL is necesary for the front disk break of the C800 K7, the rest is used to bleed the Brake Circuit

I use a ROTHEWALD BRAKE BLEEDER 0,5L for this purpose, a valve and a recipient makes the change clean and easy. I also use a syringe to empty the deposit before add the new break fluid 



The brake liquid should be changed every 2 years or when the brake becomes spongy. You should never add new break liquid to the deposit, you must change all the hose liquid everytime you have to change it. It can't be stored as it has a caducity date. Once opened it has to be used at the time