Dot4 brake fluid and silicone hose?

[JonW]

I plumbed the part of the brake system from the reservoirs to the master cylinders with standard silicone hose as i read online and people suggest that its ok to do that. However Ive since noticed that the outside of the hoses has what looks like condensation on them (reminiscent of the pint of beer in Ice cold in alex when its 12-15deg c and rainy outside, not in a desert!) but it feels a bit more like brake fluid to my fingers, unless im just panic'ing of course.

So is it true that normal silicone hose is permeable to thin fluids like brake fluid? and if so is it also letting air into my brake fluid, and hence also water... hmm...

I dont want to replace these runs unless i have to as they are all otherwise doing a fine job and nicely in place now of course...

[nikfubar]

Unfortunately Jon the brake fluid is sweating through the hoses. I've had this before, you need to use the correct type of hose.

[JonW]

bah humbug! bugger.... So what sort of hose do i need? ends are 7mm and 8mm... Im off to cry into my beer...

(cheers for your help guys!)

[nikfubar]

Dec 8, 2011 11:38:03 GMT 1 JonW said:

bah humbug! bugger.... So what sort of hose do i need? ends are 7mm and 8mm... Im off to cry into my beer...

(cheers for your help guys!)

Difficult one this, I went to a company that specalise in hydraulic hoses & they gave me a hard plastic pipe with metal brading which I used for the rear brake reservoir on my old bike as it needed to be about 800mm but for shorter lengths I have just used pipe salvaged off old rear reservoir to master cylinders as these tend to be longer. Not found anyone which sells the proper stuff, if you go to a dealer they start asking questions like what bike is it for & when you tell them it's for a hybrid it's sorry mate can't help you
One other thing I have used which works is proper fuel pipe for cars, it comes in 6 or 8mm but is chunky & doesnt look very good, suppose you could always cover it with gloss black heat shrink