have fitted rear discs to the s1 along with all new lines and put the cossie brakes on the front that were already on before.can get fluid to all calipers no probelm.rears had a good flow of fluid.fronts isnt very good.have tried bleeding a few time with no sucess.will fitting a s2 master cylinder help?its th only thing stopping me getting out a decent drive

 

clamp all the flexi hoses with proper clamps, see if you have a good pedal then?

 

will do mate.im going to stick a s2 cylinder on aswell as guys on seriesoneturbo site have needed to do the same after fitting same as me.

 

clamp the flexi's first, if there bled properly you should get a good pedal, if you don't master cylinder is fooked.

So if pedal is good with hoses clamped remove clamps 1 at a time and check if pedal remains good, when pedal goes crap again this is the corner of brakes to start looking for problem

 

I had a similar problem with the brakes on my van,took forever to bleed them,think air got stuck in one of the rear bias valve because all of a sudden we got a massive amount of air our of the passenger rear and then everything was good

 

You may find that the current master cylinder simply doesnt push enough fluid meaning pedal travel is to big. On my Fiesta Turbo I fitted cossie front calipers and focus rears and had to replace the master for a larger bore one from a Mk5 Escort as the original was not up to the job.