Motorcycle Repair: 1983 VT500C Brakes, hydraulic clutches, vt500c

Question
Chris,

I have an '83 Honda Shadow 500 and I'm having difficulty bleeding the front brakes.  I let the bike sit for a while and when I went to move it, the front brake was locked shut and I had to bleed off some brake fluid to relieve the pressure in order to roll it onto the truck.  When I opened up the master cylinder I realized that the fluid was contaminated and needed to be replaced.  I've followed the steps from the repair manual but I can't get the fluid level in the resevoir to drop.  When I squeeze the break lever, air bubbles come out of the bleeder valve, but no fluid.  Any ideas?  Many thanks in advance.

Answer
Hi Neal.

 This sounds like you have a reverse trap in the fluid line.  It is a very common problem with the newer (post 1970's era) bikes due to the configuration of the master cylinders.  This also applies to hydraulic clutches, so here is the proceedure;

1) Bleed the brake.  Make sure that all of the air bubbles that you can normally find are out of the system.

2) Check the brake fluid level and top off as needed.

3) Cover the front area of the bike, near the handlebars on the brake side, with rags. (you will see when you actually perform this whole proceedure)

4) With safety glasses on, place a wrench on the banjo fitting (the bolt that holds the brake line to the master cylinder) and with the brake lever depressed, break the seal on the fitting and (BEFORE releasing the lever)
tighten it back up.

5) Check the fluid level and test the brake.

6) Repeat steps 4 and 5 up to, but not more than, 3 times or until the brake works normally.

Let me know how it goes.

Good luck and ride safe.
FALCON