How to fix a leaky banjo bolt?

[KaTooMer]

So I finally got fed up with my crappy Brembo front brake (believe me, I tried all the tricks, it still sucks) and bought a Nissin master cylinder from an '02 Honda CRF450. Had to buy the Honda banjo bolt because the thread pitch is different (1.25 on the Honda, I think, and 1.0 on the Brembo). The Honda bolt is about 3mm longer than the stock bolt, so I added another washer to "center" the opening in the bolt with the opening in the brake line.

With this setup, constant pressure caused brake fluid to leak from the copper washers that fit between the bolt and the end of the brake line. I added some teflon tape around the threads to seal it better, and it helped. However, last night I pulled in the lever, wrapped it with a zip tie to apply constant pressure, let it sit for about a half hour, and there were a few drops of fluid still leaking past the copper washers. On the plus side, the brake lever was a lot more firm.

Any tricks to properly sealing the banjo bolt? Is there something special about the Honda brake line that makes it seal better around the Honda bolt? Would thin o-rings (replaced regularly) combined with copper washers do the trick?

Thanks.

 

[D36-108A]

You did use brand new washers, didn't you?

I'm suspicious of the dual-washer setup.

 

[marcusgunby]

Check all washers are completly flat-new ones are best each time you crack open the banjo bolt.