Black clutch and brake fluid

[biker7]

My clutch and brake fluid has gone black after only 1000 miles on a Hayabusa from new (3 months). I'm having new fluids put in by dealer. I've had several suggestions what causes this but not sure if any are correct. Anyone on here got any knowledge on this? Black fluid is not really a good idea compared with the nice clean stuff that comes out of the bottle.
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Swansea area
Fat Bob (2019)

[Bru]

Are the master-cylinder or caliper bodies black-anodised? That, or too-close-fitting plunger rubbing against m/c bore to create aluminium-oxide (unlikely)? Deterioration of seals in the m/c or calipers, due to some fault or contamination of seal or fluid?

I'm guessing it's the seals leaching out colour (carbon black - generally inert, if off-putting).

[RhynoCZ]

There are only 2 things that may turn your DOT4 black/dark and these are moisture and contamination wiht something dark/black stuff (dirt) inside the system.

Who did the fluid change? Did they flush the system with fresh fluid?
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[biker7]

Cylinders etc are black. Bike is new so seals are as they came from Suzuki. The original fluid is still there. When it is removed next week I will ask that it is flushed. I would like to find the cause and have any remedial work done. Dealer says it is due to heat?! Moisture and contamination from chain lube have been suggested by others. I'm not sure how anything can get in if the fluid is not leaking out. It looks odd. I'm also wary of reduced efficiency. I do expect it to be sorted as the bike's under warranty. Most bikes I see have nice clean fluid but some are dark to black. Puzzling why, though. My previous Busa was ok.
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Swansea area
Fat Bob (2019)

[RhynoCZ]

Moisture buildup is pretty common, that is why you have to change the fluid, so things don't corode inside, but that never happens this quick. The moisture buildup is also why they tell you in the service manual and on the caps of the reservoirs to always use a brake fluid from a sealed container.

The dirt however is something that puzzles me. There must have been something already inside the system or in the bottle of DOT 4 they used. A human error is also an option.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[MCN]

[Robby]

Fluid going properly black isn't down to water, it's down to other contaminants. The usual culprit is rubber from rubber seals, but in a new bike it could also be paint or anodising.

So the fluid going black quickly on a new bike isn't massively worrying - there are enough anodised components in the system that could have shed a little. The worry would be if it goes black again really fast, or does so repeatedly.

I wouldn't worry too much about performance. The thing that kills the performance of a braking system is water, which it will gradually absorb from the atmosphere - the system is fairly well sealed, but not perfectly. Brake fluid absorbs water to prevent the water from collecting in a single place and being a really big problem. This takes years. The recommended two year service interval is really on the safe side.
As for brake fluid collecting up other contaminants, this is what brake fluid does. It's very good at picking up anything nasty in the system and holding it in suspension. It also takes very little contamination for the fluid to look awful.