GS1100GK brakes

[Rockman]

I have a problem bleeding my front brakes. When I got the bike the front calipers were seized. Stripped and cleaned them. Just a bit of dirt. Master cylinder leaked, so I put a kit through it. Looked pretty good inside.

Now I cant seem to get it to bleed properly. I have some brakes, but they are soft and I can pull the lever back to the handgrip if I try hard enough. I tried pumping the lever quickly, bleeding the mc etc as per another thread but no good. There doesnt seem to be any air in the fluid any more - I've run about 600 ml of fluid through it so far.

Any suggestions? Do the brake lines go soft with age (its a 1985 bike with 32000 km on it)?

thanks, Phil

[Steve]

Yes, the rubber brake lines go soft with age. It is highly recommended to get new stock brake lines or upgrade to stainless steel lines.

Since you just put a kit in the master cylinder, you may not have all the air out of it yet. Remove the brake lever, open a bleeder nipple or a banjo bolt, use a screwdriver to push the piston in as far as it will go. This will be much farther than the lever can push it, and it will get rid of that stubborn air bubble that is just before the banjo fitting.

.

[Nessism]

If the calipers were sticking you can be assured that the brake lines have scale on the inside. As Steve says, time to change the lines.

[Rockman]

Thanks, I'll try pushing the piston in as far as I can and see what this does. If that doesnt work then its new lines and try again. Phil

[almarconi]

Once you replace the lines try bleeding the brakes using this method. You will need a large syringe or better yet a mityvac or phoenix injector.

Take a bungee cord and wrap around your brake lever so that the lever is held half ways (this will prevent fluid from returning to the MC). Remove the cap to your master cylinder, fill up about half way with fluid. Attach a piece of rubber tubing to the bleeder valve on caliper #2. Start by injecting brake fluid into caliper #1, open the bleeder on caliper #2. Keep pumping fluid into caliper #1 until no air appears in the rubber tubing on caliper #2. What you are doing is bleeding caliper #1, the lines, the splitter and caliper #2.

Release the brake lever. Close bleeder on caliper #2. Continue to pump fluid into caliper #1. The fluid will now travel to the the upper hose and into the master cylinder. Continue to pump fluid until the m/c is full and then install the cap. Close bleeder #1. Test your brake lever, it should be hard. If not, pull the lever in as far as you can and bind it to the grip using the cord. Let it sit like this overnight. In the morning, release the cord, the lever should now be firm.

I have used this procedure countless times and it produces a firm brake lever.

I just replace the original lines on my GS with braided stainless and the difference is like night and day. Before the brake lever would almost touch the grip. The condition seemed to worsen after a long trip when everything got hot.

[Nessism]

One other comment, not sure what kind of parts are available in your part of the world but I've seen some problems with K&L caliper kits before - they wouldn't let the caliper piston move properly. Replacing the kit with OE parts solved the problem. Something to consider if you are using K&L.