Calling all Technicians...

fimduc · 08-02-2003, 04:28 PM

Ok, this is a good one. Picked up the used 2000 SA in the late spring, gave it the good once over, pads and tires all good ...put about 3500 miles on it.....never was one to use much rear brake though......yesterday I decide to see if I can actuate the rear ABS by giving it a good stomp......hmmm, no lock up must be working though the the back brake by itself seems weak....oh well, love that front brake.

Buy the Craftsman lift today, jack it up start poking around. Rear brake fluid resevoir looks, full with the flashlight....but maybe not. Pull the top to the resevoir, pull the black insert.....in with the finger...uh,oh bone dry! Guess I have been using pnuematic brakes in the rear.

So, before I get out the Service Manual, do you guys think I have messed up any components on the brake system by running it dry and using it? Are the hydraulics front and rear on a separate circuit? I suppose I should just go through the bleed and refill process and go for the test ride. Probably a good time to go over the front as well.

BMWSBK · 08-02-2003, 06:13 PM

Your questions scare me. At least you haven't killed yourself...yet.

Fill it up with DOT-4, bleed it and see how it works. Chances are you ruined the Master Cylinder though. Front and rear brake are independent on your bike.

RoundelRider · 08-02-2003, 07:53 PM

If you dont use your rear brake much (since you just noticed it) i dont think any major damage has been done hitting it one good time. Leaves me wondering where the brake fluid went??? check the caliper bleed nipple, around the pistons and hose fittings. check the master cyl. hose fitting and where the linkage rod comes out. also the res. fittings.

Id keep a watchful eye on this!!

Good Luck.

John

pdonnell · 08-02-2003, 09:19 PM

Fill up the rear resevoir and bleed then put something heavy on the rear brake pedal overnight and check for leaks in the morning. Before doing it I'd get new brass washers and bleed nipple and install. (just to save some hassle if this is origin of the leak, easier to work on it now thats its dry)

EZ-RIDER · 08-03-2003, 06:01 AM

My bet is that someone bleed the Rear brake and never refilled the resevoir, Do what pdonnell said to do.
I don't think you will see any Leaks If it was leaking I think you would have seen it when you bought the bike.
Also you are going to have to removed the tank and bleed the ABS system or the brakes will feel ****ty. And since you will have to do that
I would also bleed the front as well.

CarlosT · 08-03-2003, 09:09 AM

You gotta bleed the ABS first. The rear brake is a b itch to bleed...I still haven't gotten a decent pedal back since my draining the reservoir snafu. Gravity is all wrong here and working against you. I think that my next move will be to crack the brake line right at the master cylinder and see if the air's stuck there.

Take off the fairing, prop up the tank with a piece-o-wood, fill up with DOT 4 and enlist a buddy to help you. There's no really good way to hold up the thimble-like reservoir and bleed at the same time.

I would also reseach how you got a bone dry reservoir to begin with...

fimduc · 08-03-2003, 09:31 AM

Thnaks guys. Good advice. I did some past searches on the brake bleeding scenario as well. EZ, I think you might be right about the resevoir never being full, as I keep the bike in my garage and have never noticed any fluids. I'm always giving it a good look at all the seals, gaskets and hoses.

Got her up on the Craftsman lift and got a good Sunday project in front of me.

SBk, ease up on the stuff about not killing myself "yet"....I come from the Keith Code genre, "the rear brake is an emergency brake" and ........I of course want it to work but I certainly don't give it much thought when I am riding.

Let's hope for the best

CarlosT · 08-03-2003, 09:35 AM

Not having a rear brake at MITM was a little unnerving but I'm a front brake kinda guy anyway...just wished I had a little "settle down" rear braking once in a while.

CarlosT · 08-03-2003, 10:20 AM

Kevin you've got mail, dude

I sent you a pretty big file (2 MB) so I hope you got some bandwidth

Good luck and please report in as you make some progress. I'm definitely interested in how you make out with the rear brakes.

RoundelRider · 08-03-2003, 10:24 AM

Im the same way with the rear brake....never using out of habit. Id like to learn the method of trail braking.

John

CarlosT · 08-03-2003, 10:28 AM

You push your right big toe down and voila...there you have it...rear braking

Bails · Bails's Garage

Low fluid level may mean worn or no pads ! Check these also

roger albert · 08-04-2003, 09:14 AM

Good point.
If fluid was already a bit low, and the pads wore, the fluid could drop below being visible, but still not leave a dry cylinder. Would be an extreme case, but certainly possible.
later
roger

CarlosT · 08-04-2003, 09:17 AM

I'd worry about a leak somewhere. If anything reservoirs are often overfilled by bozo techs not looking at the pads. When you go to put new pads, your cup runeth over

fimduc · 08-04-2003, 09:44 AM

Can't find any leaks after keeping the system under pressue overnight. Pads at 9500mi seems to have about 50% wear remaining, F&R. I'll give it a test ride tonight after I get the Suburban Peg Kit installed.

Any experience using Speedbleeders as an alternate to the typical nipple?

sud-z · 08-04-2003, 11:46 AM

I have a speed bleeder on the rear caliper of my RSL. Works well, but it doesn't work at all if your trying to pump fluid through dry lines. You need to have at least some fluid in the lines in order for it to work.

-Shawn

EZ-RIDER · 08-04-2003, 11:56 AM

They don't make a speed bleeder for the rear, only for the fronts.
If you find one let me know.

CarlosT · 08-04-2003, 12:25 PM

The rear bleeder is a lot smaller than the front on my 2001 SA.

CarlosT · 08-04-2003, 12:30 PM

Sgirl:
Correction...the Mac-Pac dinner at Manayunk is tomorrow night Tuesday 8/5 at the Manayunk Brewery on Main Street. Marc, the organizer of tomorrow's dinner, remembers you well. C'mon down

Dave Hopkins · 08-05-2003, 09:17 AM

When I bought my "S" it was abt a year old, had 3000 miles on it, rear tire was square, front was cupped. I was shocked when I checked out the rear brake, completly worn out=zero lining. My prior "S" had 18,000 on the clock and was on its second set of linings up front but plenty in the rear, I guess Squids can do that to rears!