brakes, hard time building pressure.

Posted by Clepto35 on Jun 08, 2012; 9:33pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/brakes-hard-time-building-pressure-tp4022531.html

I have an 81' honda CB750C and the one thing is keeping me from the road is the brakes are not grabbing very well.

I bled the air out of both calipers  with a bleeding kit and I cracked open the banjo bolts at one point beforehand.  It is a new master cylinder (I believe it might be aftermarket) but there was DOT 4 brake fluid in the system.  I think I got most or all of it out with the DOT 3 fluid.  

Is there a chance the DOT 4 fluid might have ruined the seals in the master cylinder?  Just so you know I did do some work on both front calipers and I can see both of them move and grab the rotor when I apply the brakes and there's no leaks from them.  

I am at a loss for words.  Any ideas would be appreciated!