brake fluid question

Ok ive got a question regarding the brake fluid. When you top it up everythings fine. However on going down steep hills the level drops below the lower mark on the window (naked curvy front res) Is this something to worry about? Also ive changed to 5.1 And apart from the colour (clear as opposed to brown) it seems thinner. Is this right?

Now lastly the rubber seal on it is flat normally. But ive noticed that on the rear one its like gone into a conical shape. Like if you’ve stuck your finger in it and pushed. Any idea why?

Also is there any benefit with 5.1 stuff?

How bloody steep is this hill! The rubber gromit in the res is designed to be sucked down, so as the level drops the air goes in behind it creating a sealed 'moving' area. So as long as you have topped it up and kept it with minimal air gap you should be fine.

I thought the 5.1 was used by racers as it doesn't boil as easily, but the pay off its that its got a higher water absorption. So its more likely to go spongy over period of time.

Think you might need to top up the brake system and re-bleed it properly from the nipples and banjos.

[yorkie_chris]

Dot4 is fine. So long as it's near full mark on flat it's fine.

Grinch. He lives near me, the hills are that steep.

Ive blead it through with about a bottle and a half of fluid and the leavers very firm.

Seems to pull up ok as well.

Originally Posted by yorkie_chris

Dot4 is fine. So long as it's near full mark on flat it's fine.

Grinch. He lives near me, the hills are that steep.

ok cool chap.

Originally Posted by yorkie_chris

the hills are that steep.

That shouldn't let the brake fluid disappear from the inspection window though.