I recently bled the brakes of my 81 xs400 and it's the first time they've been bled in 20+ years ( found the bike in a barn a year ago). I didn't have a bleed kit so i roughed it a bit. I disconnected the fluid line at the caliper and drained all the black mess out. I seal it back up, added the new stuff and ran it through. I pumped it through the bleeder valve then. I sealed everything back up and the pressure seemed to have dropped a bit. Stopping felt smoother though. However, now there's a leak coming from somewhere when I press the brake hard and it doesn't look like either the bolt for the fluid line for the bleeder valve. I'm gonna try the baby powder trick tomorrow. Any thoughts? Is there a caliper rebuild kit for stuff like this (seals, etc)?

  christoph21 said:

I recently bled the brakes of my 81 xs400 and it's the first time they've been bled in 20+ years ( found the bike in a barn a year ago). I didn't have a bleed kit so i roughed it a bit. I disconnected the fluid line at the caliper and drained all the black mess out. I seal it back up, added the new stuff and ran it through. I pumped it through the bleeder valve then. I sealed everything back up and the pressure seemed to have dropped a bit. Stopping felt smoother though. However, now there's a leak coming from somewhere when I press the brake hard and it doesn't look like either the bolt for the fluid line for the bleeder valve. I'm gonna try the baby powder trick tomorrow. Any thoughts? Is there a caliper rebuild kit for stuff like this (seals, etc)?

There are seal kits available and seems like the 83 XV750 is using the same seal kit too.

Here's the site:

http://www.boats.net/parts/detail/yamaha/Y...0047-00-00.html

I came out this morning and checked to see if anything had changed and there was no pressure and the was brake fluid on the ground. It really sprayed out when I applied pressure to it. Upon introducing that new fluid, it seems that it corroded the rest of the old seals away. I'm going to buy a kit and hope that I don't need a new caliper.

seal kits are easliy available and so are the brake pistons ( i got mine done in stainless steel)