black crud in brake fluid

[Punjistick]

So BadBoyBilly and I just changed the brake fluid in my brother's bike ('01 600 F4I). It was brown and nasty in both brakes, but the rear brake had tiny black chunks of what I can only guess is rubber brake line? When we put the new fluid in, no black chunks came out.

I read the service manual and I didn't see anything about when to replace the lines other than if they are cracked or worn.

Think the lines need replacing or is it most likely just congealed brake fluid?

Thanks.

[Rye]

Originally posted by Punjistick
So BadBoyBilly and I just changed the brake fluid in my brother's bike ('01 600 F4I). It was brown and nasty in both brakes, but the rear brake had tiny black chunks of what I can only guess is rubber brake line? When we put the new fluid in, no black chunks came out.

I read the service manual and I didn't see anything about when to replace the lines other than if they are cracked or worn.

Think the lines need replacing or is it most likely just congealed brake fluid?

Thanks.

I would not assume it's only the brake line. It could be a seal from inside the mc. Rebuild time...I'd swap the line to a braided setup too.

[OreoGaborio]

Originally posted by Rye
I would not assume it's only the brake line. It could be a seal from inside the mc. Rebuild time...I'd swap the line to a braided setup too.

i agree... but... braided rear? what's the point?

[Punjistick]

cool thanks for the help. Yea, braided rear is probably overkill and my brother locks the rear too often anyways.

[Rye]

Not for performance. Steel braids for abrasion resistance. I get rub marks on my lines where they mount to the swingarm. May just be a design issue on my bike.

[Punjistick]

oh good point. I know on my brother's bike the rear brake line goes through a piece of rubber tubing which is supposed to protect it.

[Billy]

Dude I've never seen brake fluid so nasty. Tha'ts probably the original brake fluid!!!!

[Punjistick]

I wouldn't doubt it.