Hi guys, I've got a 99 CB400, been doing recent work on it and when it came to bleeding the front brakes,they simply wont bleed..
I've checked the master cylinder located below the reservoir and had a worn seal changed in it. After that,checked if it was working and bled just the master cylinder with the hoses to the calipers disconnected, than tried to bleed the calipers but no luck,just a few bubbles from time to time. Sometimes the bubble would actually go back into the hose instead of going completely out.

Can anyone help please from personal experience or please redirect me to a post that sheds some light on this situation? I have also checked the hoses, there are no tears. Could changing the washers and putting new ones help?

Try pulling the pistons out slightly, I find it helps get the fluid moving.

With twin disc systems sometimes you need to clamp the lines to one of the calipers and do them one at a time.

Occasionaly with very stubborn calipers i pull the pistons out completely and fill the capiler with brake fliud then refit the pistons so that they just seal, then you wipe then off and reconnect the brake lines so that when you push the piston back in the air is pushed back up the line into the master cylinder.

prawny12009 wrote:Try pulling the pistons out slightly, I find it helps get the fluid moving.

With twin disc systems sometimes you need to clamp the lines to one of the calipers and do them one at a time.

Occasionaly with very stubborn calipers i pull the pistons out completely and fill the capiler with brake fliud then refit the pistons so that they just seal, then you wipe then off and reconnect the brake lines so that when you push the piston back in the air is pushed back up the line into the master cylinder.

Your contribution is much appreciated! Will try that as soon as I'm off work!

Still no luck..do you think the washers that go with the hose and banjo may cause air to enter the system therefore make it immune to bleeding?

PROBLEM SOLVED!
Dont have time to write it down now but if any other bikers suffer this same problem,send a PM