After five years it's time to change the fluid - as part of this year's service which I'm doing in bits when time permits.
The brake fluid change and service will follow in a later post.
First the equipment. An old bleed tube, which is nothing more than what looks like bunsen burner gas pipe with a screw in the end and a slit at the end along the sidewall. This is so that the fluid & air can escape through the slit, but no air gets back in. Like breathing out through closed lips. I also have a Waitrose olive container with a hole in the lid for the tube. This is to collect the old fluid - and it won't spill with the lid on. Finally a small top from an aerosol can to act as pourer.

This job is messy. Brake fluid can also damage paintwork and there isn't much room to do it. First thing was to remove the black dustcap on the bleed nipple and the insulating tube from the master cylinder. Next I put some newspaper underneath to catch the drips. There will always be drips.

The way I do it is this - if you first empty the master cylinder and refill with new fluid, you don't have to pump so much old fluid through. So I have a "Fluid Transfer Tool" from Agriemach.......You can use the wife's chicken baster at your peril. You can see how cloudy the old fluid is in this shot.

It took three fills to empty the master cylinder.

You won't get air in the system by doing this, as the air will rise to the top as you fill with new fluid.
Next I loosened the bleed nipple (11mm ring spanner). Make sure that the bleed tube is a good fit, because the hydraulic pressure can blow it off with the risk of a small jet of fluid, which may go anywhere. Mine popped off a couple of times - so I got my drips. After a few pumps, clean fluid started to emerge - it probably took about 15 pumps, and several top ups of new fluid. Once it runs clean, tighten the bleed nipple, wipe down and refit the dust cover. Check the master cylinder level and replace the cap. Check that it works OK. I used Duckhams Dot4 for this job, and it took about 500ml. The next picture shows the clean fluid which eventually emerged - which is significantly cleaner and lighter than the old fluid.

This is nearly clear. And don't panic, I'm not reusing fluid, this is just to illustrate how clear the new fluid is - like white wine.........of current vintage

Looking at the state of the old fluid, I really need to get the brakes done, but it will have to wait a while longer.