Signs you need a new clutch slave cylinder 1150GS

I've got a 2002 1150GS with about 47,000 on the clock. I had to bleed the clutch after the banjo on the master came loose and sucked in some air. While bleeding I noticed the fluid was an interesting color in the master reservoir. Usually old fluid is black or clear. Black is water contamination. This was a brown color. Huh. Odd. I found a thread, http://www.advrider.com/forums/showthread.php?t=491635, about bleeding the clutch and his fluid has a similar look to it.

OK. I'm guessing this is a no-brainer and the fluid tells the story. But, before I put down some money for parts or give it to the stealer who quoted me over 300 for the job/diagnosis....I want to be sure.

Other possible symptoms:

Tractor like shifting. Its very "CLUNKY". Meaning each change is a very solid CLUNK when gears are changed. This seams inconsistent and I can smooth it out a bit, but I don't know. I am told the GS has a very "industrial" feel to the shifting mechanism.

Shifting. Sometimes it won't find second naturally or will go into neutral instead of first. This may be user error on the latter, but I very deliberately upshift to try and alleviate the issue.

POssible "skittering" sound. When hold the clutch in, sometimes I can hear a skittering sound while the bike slows to a hault. I'm new to bike so this may be normal....or it may be the dogs slipping over their holes because the clutch isn't operating correctly. You tell me.

I'm not afraid to turn wrenches here...just need to know what direction I'm headed.

Thanks.

I just replaced the slave on my 1200..the engagement point was the giveaway for me..I had no engagement until lever was nearly fully out..

AFTER I replaced it..I notice the shifting is MUCH smoother..apparently, getting clutch fully disengaged, makes a difference..

My fluid had not been changed in 6 years and 80K miles..it was brownish..I think..I just used suspension fluid to do the new one..10 wt, cause it's what I had..but 5 would have been better..and I may change it..

Muddy brown fluid -> bad slave. Replace it.

What Anton Said!!!

Don't forget to replace the input shaft rear seal. It is an updated seal. Drill a small hole. Start a sheet metal screw. Yank the sucker out with a slide hammer. Job was easy once I pulled the wheel, muffler and shock. I disconnected the hydraulic line at the master, freed the bleed line from the frame rather than remove the lines from the slave while it was still mated to the gear box. Suggest you order a 2" over from Spiegler. When you attach the new hose to the slave kick it out some to prevent interference with the gearbox. I flushed w/ DOT 3 before mounting slave to box which cleaned out the master and also saved on the cost of Dot 4 for the final fill. I added a blob of clear syn grease to the throw-out bearing.

edit: As others explain below the input shaft rear seal is accessed from the cavity once the slave is removed. This keeps gear oil from entering the cavity and fowling the slave and eventually the master. When the slave begins to leak DOT 4 the seal is contaminated and must be replaced. Some have used picks to pry out the seal but I feel that it will be far easier for most to drill (one 3/16"? hole) the seal and use a slide hammer. If I recall correctly the updated seal is brown instead of grey. Steptoe had previously advised to seat the new seal all the way up against the bearing. I never removed the push-rod for fear of damaging it.

The slave needed to be tipped up as it was withdrawn from the cavity (reinserted the same way). The paralever needed to be raised a bit then the slave, with hoses still attached, rotated to withdraw it past the round gear box cross member. edit: I probably disconnected the hoses once the slave was free of the gear box then worked it out past the crossmember.

I heated the factory bleeder/fill valve to melt the thread lock and remove it from the end of the bleeder but I could see how some might mangle the bleed hose doing that.

I reattached the oem hose to the master after disconnecting it from the slave so I could give the master a good flush with DOT 3 to clear it of gear oil contamination. I installed the new hose then bled prior to mounting up the slave. Aside from initially having interference at the gear case owing to the slightly different bend that Spiegler uses on its slave side banjo this job went smoothly with no special tools required. Use caution on torquing the tiny banjo bolts as they are special and expensive. The mount bolts are also low torque.

Are you describing the the transmission input shaft that the clutch disc rides on when you say "input shaft"? The transmission input shaft seal in my 01 R GS bike has 61k miles on it and is not leaking. Was there a problem with this seal design? I ask because mine is still exposed due to unfinished clutch service. What is the benefit of the short bleed hose besides maybe a less cluttered look.

You're refering to the input shaft seal, input end.

Vintagerider is talkig about the input shaft seal, output end.

On mine the engagement point has been like this for a long time. Almost all the way out, Sometimes when I take off at a stop I wonder if I have any clutch or did it quit on me. I wish I can get an answer for where the engagement point should be ??

And the hose as well.

Jim

I just did my slave and input seal earlier this year. I had also just upgraded to Spiegler brake lines, and so thought I'd do the same with the clutch line, and ordered the part through my local dealer in preparation for the job. However, the line that they sent wouldn't properly mount to the clutch slave because the fitting on their line was wider than on the stock line, and didn't leave enough threads left to torque the bolt. Spiegler's response was that they didn't know why I had a problem (even though I sent pictures) so I sent it back. I ended up re-installing the stock line, rather than ordering a new OEM line, because it was in fine shape. They are made out of a sturdier material than the brake lines and didn't appear to degrade internally like my brake lines.

The problem is contamination. Those who do not change the hose, and do not get it thoroughly cleaned out, often end up with Master Cylinder and/or slave cylinder failures.

Jim

Ah, got it. I didn't have that problem. I flushed the system through before the change, and also my work was precautionary anyway, as I was doing a lot to the bike at the time. My fluid didn't show any problems yet (although there was a little oil in the slave chamber). But definitely good point for the OP.

Still, just from my experience anyway, heads up on the Spiegler line as a substitute.

I was looking for another mention on the seal...I saw it once but couldn't find it again. Do you know the part number or BBY link? I've got a BMW dealer walking distance from the house if it comes to that.

Now I'm trying to wrap my head around this thing before I tear into it.

You take off the wheel, the shock, and the muffler. The slave cylinder goes around the output shaft and has a throwout bearing on the end.

Now for the clincher.

By just removing said parts, how do you get access to the slave? Shouldn't it be sandwiched between the transmission and the driveshaft? How does the slave come off the same "line" that powers the driveshaft? I'm sure its totally obvious when it comes apart, but coming from the automotive world, you shouldn't be able to change a throwout bearing without splitting the trans off or the driveline.

The slave is located in the middle of the back of the transmission. It is in front of the frame member that crosses behind the transmission and in front of the shock. You remove the wheel and shock to get at the slave. You may need to loosen and displace the electrical box. It looks not possible to get the slave out past the cross bar, but I have managed it on two different bikes.

Starting point - there is an article in the hall of wisdom (link at bottom of page).

You should also look at one of the online BMW parts fiches to get a better picture.

You are over thinking this. Even though Hans and Franz made this a goofy design, it is not as screwed up as most car designs.

There is a thread with pics in the G Spot Faq, section 4.14.

Not really like a car clutch..no throw out bearing...simply bolted on back of tranny with a couple bolts...takes twenty minutes to swap...+/-

Thanks everyone. I've got a good handle of the replacement process....just trying to understand how it all plays together.

I looked in there, its under 3.35. THe problem is...all the picture links are gone. Looks thorough though.

WHOA! Does the power make a sharp right out of the engine (when looking from the back)? and drop down via gears? So the driveshaft isn't inline with the crank shaft...its to the right and down (from the back)? If so...now it makes some sense. If not...more lost than ever.

Look at http://www.realoem.com/bmw/showparts.do?model=0495&mospid=51759&btnr=21_0145&hg=21&fg=21

Part 1, the clutch housing, attaches directly to the end of the crank. The teeth on the periphery are where the starter engages to turn the crank. No right turn until you hit the FD. The rod actuated by the slave cylinder pushes the spring (part 4) at the center.