Brakes

[BooG]

So...finally got some time to replace hoses. Stainless ones seem a bit shorter than stock ones..I'll try and get a photo up at some stage. I decieded to replace the contaminated pads as well. A fairly straighttforward job, but the fluid was a scource of interest. I have replaced it annually till now, but when I took the Brembo calipers apart for a cleanout, the last bits of fluid I drained had some nasty brown looking crud in them. I blew them out and rinsed the bores with new fluid, but this begs the question....when you do an annual brake fluid replacement, does the fluid nearest the pistons and seals actually get replaced? Looks like mine had been festering there for some time, despite bleeding new fluid through the system not so long ago. I have re-filled the system and left it to stand for a while to try and allow air bubbles to rise. Any more advice at this stage welcomed! Also, I noticed that my discs are scored. Would it be worth getting them skimmed? The wheel has to come off anyway so I can replace the tyre.
Thats all for now.

[its_only_me]

It's funny you say that your stainless hoses are short, I have just changed mine to stainless, and mine were 30mm shorter than stcok rubber hoses, I had to take the hose guides off of the yokes as they wouldn't run through.

[Bob_Roller]

I had alot of problems getting stainless brake lines in 1991, I had to go as far as removing the lines and take them to Luftmeister in the Los Angles area . So I stopped by and in 5 minutes I had the correct lines for my bike. When you bleed the brakes, you don't get all of the old fluid out of the system, only way to do that is to disassemble and clean the individual parts. As far as having the rotors machined to remove the grooves, the minimum thickness for the rotors is : .181 in. By the time you get the grooves out there won't be enough of the rotor left to safely stop your bike. So you either live with it, which is what most riders do, or replace them at $230 each for OEM parts, or about $200 each for aftermarket steel rotors.

[Justin B.]

Well, they will probably still stop you plenty good if they're a hair too thin but will tend to warp given the slightest excuse.  Of course, if you gott turn 'em down to the point where you could shave with it, then if probably wouldn't stop very good either!  

[Rob Valdez 79 R65]

A picture is worth a thousand words:


click on picture for full size

[BooG]

Yeah, I had to invert the hose guides so the lines would fit ok. I wonder why they come up short?
I think the discs can stay as they are then. Is there a bedding in period for brakes?
Great Photo! Mine wasn't as bad as that, but in that direction. Maybe its worth a strip down and clean bi-annually, eh?
Tremendous thanks as usual!

[Rob Valdez 79 R65]

Yeah, a lot of folks here swear by their braided brake lines, but by going with stock rubber, I had no fitment issues.

Hopefully taking the old originial ones into a shop that makes them on the spot would avoid length problems, also.

[Bob_Roller]

Before you take the bike for a ride, when the front forks are fully extended, are the brake lines still long enough? I don't think you want the brake lines to be tight before the extend stop is reached!

[Justin B.]

Good point, good thing to check...

[Rob Valdez 79 R65]

(I think I deleted Boos post - sorry Boo)

Boo said:

Wicked cat thing.....
now then, bled the brakes, checked the full fork extension pull on the new hoses...seems ok...they end up straighter than the old ones, but there seems to be plenty of play. The hoses came with copper washers and the upper fittings don,t fully engage the washers. There is no leaking so I guess that's ok?
The brake lever still does not feel right...it pulls in a little to far on the first pull, and then seems to arrive at where it should be on the second pull. I have tied up the lever with a bungee and tapped the solid and flexible lines to release any further bubbles, and will bleed again tomorrow. Cold snap in the UK means that I bet I have a tempremental start up on my hands! I found the pictures posted by Justin on the other brakes link, and they were really helpfull. Pictures really do say a thousand words!! Oh yeah, and what colour should new brake fluid be? Does it have a shelf life? I guess being hygroscopic, it must have. Clear, or kind of off white...piss colour maybe,.... assuming you are fully hydrated.

[Rob Valdez 79 R65]

But luckily, using my Back button, I was able to copy & paste it into a replacement post.

Now then - Shelf Life - I assume none.  Once the bottle has been opened, I don't even think about keeping the leftovers.  I have heard that once the air hits it, it is never the same.  Especially if you save it until your next fluid change.  For that reason, I buy as small a bottle as I can.  I don't know how to properly dispose of the stuff, but I am sure a landfill is not it.  

[Justin B.]

Boo, squeeze your brake lever in pretty hard and lock it in position with a tie-wrap.  When you come back the next day it'll be hard as a rock...

[Ed Miller]

My local information for brake fluid disposal is to add it into your used motor oil.

This tells me they are probably burning both at the garbage burner/electricity generator, as the two compounds aren't very similar.  But what ever, it's better than it going into my stream.

[Semper Gumby]

Aeroquip in Atlanta provides walk-in service.  They are actually in Decatur.  I brought my old lines in and he made stuff on the spot in 10 minutes.  404-296-7997 was the last number I had for the guy.

[BooG]

So...the brake saga continues!! Tiny amount of fluid visible between the joins of the left calipers seems to suggest that the o ring might have failed, so I've decieded, seeing as they're coming off again, to do a brake overhaul.. pistons as well! All the kit has arrived from motorworks up north, and tomorrow is the day!! I'm going over to France in about 4 weeks, so I want to get them sorted as I've got a few more maintainance tasks before I go. Very helpful info up to now...'specially the bit about applying pressure to the brake lever overnight! Worked great..
Brake lines seem OK....do people wrap PTFE tape around the threads of the bleed nipples?