quick question, what fluid for a Pro-stop disc brake?

[jonnyboy666]

mineral or dot? i have the manual to do a bleed on a pair of brakes but it says "mountain cycle brake fluid only" but doesn't say what it is.

any definite idea?

 

[Stretch79]

Dot 4 or 5.1 usually i believe

 

[jonnyboy666]

@Stretch79 are you 100% sure?!! it's a customers bike and i've never done nthem before!!

 

[Stretch79]

@Stretch79 are you 100% sure?!! it's a customers bike and i've never done nthem before!!

What are the brand of brakes?

 

[mk one]

Not sure, but have seen reference to people using Shimano Mineral.

@yakboy may be able to help having filled a few Pro-Stops, reference here to automatic transmission fluid which i think is mineral based -

https://www.retrobike.co.uk/threads/1992-san-andreas-mountain-cycle.408029/page-24#post-3374095

 

[jonnyboy666]

mountain cycle pro stop, i didn't realise before that these were cable actuated hydraulic brakes, the manual doesn't say what fluid it is

 

[yakboy]

Cable prostops use automatic transmission fluid

 

[jonnyboy666]

ok, so what is that?

 

[yakboy]

ok, so what is that?

It is what it says on the tin Any motor factors will stock it

 

[fennec]

ok, so what is that?

ATF, check any auto parts store
its a high viscosity hydraulic fluid with detergents and corrosion inhibitors in it, for context
its also suitable for mineral oil based modern hydraulic disc brakes

its not too uncommon with older cable actuated hydraulic brakes like this, since the fluid is never really expected to be changed or bled or anything like that, and ATF lasts basically forever