Topic: 400F Front disk brake not fully releasing.

[Kurt V]

On my '76 400F the front disk brake does not fully release after applying the brake. My past experience has been that old brake lines can swell on the inside and create this type of situation. So I thought I should at least replace the soft lines. Problem is, where do I find them? A link would be quite helpful! Thanks!

Any other suggestions as to why I am having the problem with the brake not fully releasing? Thanks!

[Powderman]

 This place makes quality brake lines for vintage bikes and will custom make ones for you at a very reasonable price.


http://slingshot-cycles.com/

[Kurt V]

This place makes quality brake lines for vintage bikes and will custom make ones for you at a very reasonable price.

http://slingshot-cycles.com/

Oh my those are some nice looking lines! Thanks for the link!

[flybox1]

First, in the master cylinder cup, there are two holes, one of which is a fluid return hole.  Both are very small.  Take a bit of wire, or a needle, and poke out these holes to loosen any debris that might be blocking the return of fluid.

The replacement of old worn lines does help.  Slingshot cycles is a great supplier, and he's a forum member.

If you do go the route of replacing the lines, You should also do a piston o-ring replacement, check/replace a pitted piston, and maybe even a MC rebuild kit.
Its all 30+ years old.  Rubber parts dont age well.