Oilhead Clutch Slave: Replace ‘em All?

I'm two for two on clutch slave replacements. ‘04RT at 30K miles and just yesterday my ‘01GS at 45,000 miles. I just did the GS as a precaution and am glad I did. It was slightly weeping, the fluid had absorped water and there was about half a teaspoon of crud on the bottom and the bearing was dry, loose and rattling around. When I did the ‘04RT it had 1/8” brake fluid gel weeping out.

The job's a bit of a pain:

—remove seats

—remove left and right seat adjusters

—remove rear brake caliper

—remove rear wheel

—remove muffler

—remove catalytic converter

—remove left shock adjuster

—remove shock/strut

—tape mud flap to fender

—detach zip tie for clutch bleed

—drain clutch master cylinder

—remove clutch slave (very fiddlely job), scrape gasket from transmission

—overhaul/replace slave cylinder

—reassemble and torque most bolts

—fill, bleed and check for leaks

Took about 2 1/2 hours.

My experience makes me wonder if any slaves don't fail ... and given that a failure might require clutch replacement, should we all just replace them every so often.

I replaced the clutch slave on my '00 GS in 2011 at around 45,000 miles. It was pretty gross in there. For me it was a good winter project - before kids. Now with many other family duties on the evenings and weekends the days of puttering about on the rear end of a BMW are gone. That said, I am hoping to pick up an '04 RT this weekend. I figure I'll have 5 good months of winter to pull it apart to inspect and replace!!! Just doing it due to age, not mileage (22,000 KM) . Wish me luck.

I think the problem is that some last 80K miles, some last 20K miles. You'd hate to take one out at 40K and have it fail 20K miles later. I think the key is to pay attention to your clutch engagement point. If it changes suddenly you slave has gone bad.

I think the problem is that some last 80K miles, some last 20K miles. You'd hate to take one out at 40K and have it fail 20K miles later. I think the key is to pay attention to your clutch engagement point. If it changes suddenly you slave has gone bad.

Discounting police bikes, we rarely saw it (low miles) when they were newer models until higher mileages.

Plenty of examples 80-100,000 with original.

But it seems there is a range with outliers.

Know your bike.

Tough question. I have not experienced a failure myself. Perhaps because I have changed the fluid annually, and greased the bearing every 5 years. I have no idea how climate and mileage affect the grease, nor what would be a good interval to check that bearing. No doubt anyone picking up a used bike it's probably quite wise to inspect that bearing. I agree, it sure is a pain to get to it for inspection.

GSAddict has greased his periodically and has something like 175,000 km on his original. He has seen a lot of them and believes lifetime has to do with how much grease was there initially.

My RT was in bad shape at 8 years 30 K miles. The GS at 17 years 40K miles was only weeping slightly. Given the cost of a replacement versus the amount of time to do the job, I decided against overhauling it and went with a new unit. This replacement was very well greased.

When you consider the cost of a failure—clutch replacement and all the work that entails—Inspection is warranted. Because I didn't buy a spare first, I had to take the bike apart and put it back together twice, about 6 hours. Now that the fleet is old, if I bought another Oilhead I'd just replace it right away.

I had to replace the slave cylinder on my '04 R1150RT (sold) as well when I checked the trans input shaft splines which were pristine. The front brake master cylinder assembly on my '93 R1100RSL was replaced by me last year to the tune of around $500. This was the second time the master cylinder was replaced the first by the original owner. The early master cylinders leak because of no corrosion preventive coating of the older cylinders. Wonder if the same affliction isn't what effects the clutch slave cylinders. Ahhhh yes, nothing like BMW quality. Thank God!

With a roadster boxer bike like a Rockster, the access job to get at the Slave Cylinder is much easier and you don't have the usual plethora of rear-frame bolts to remove; just the four :- one each side above the cylinders ( hard to get at 'cos of the harness / hard rubber pipework, etc. ) and the two foot-peg bolts that go into the X-bar in front of the shocker.

And you don't have to raise the rear frame very high - just enough to be able to pull out from the right-hand side that pesky crossbar that gets in the way of easy access to the slave's fixing bolts.

With the rear frame slightly raised, you have more space between the slave's banjos and the bottom of the air box.

See my vodiodi :-

AL in s.e. Spain - the job would be so much easier on the knees and back if one had a lift-table....

Al, Nice video, but you don't need to move the frame at all.

Thanks for the compliment Roger.

Before I embarked on that shoot and plan, I watched loadsa threads about getting the slave cylinder off, and it seemed unecessarily fiddly trying to do so with the X-bar in place.

Can you possible give me any tips as to how to extract this black, wrinkly, contaminated seal at the back of the cavity that the cylinder sits in ? Middle son the Copshop Fleet Maintenance Manager suggests getting from Amazon a "seal pick kit". The new-style seal is orange-coloured neoprene, yes ?

I have replace a transmission seal yet but your sons advice sounds good.

Hi Guys, Im noticing lately that my clutch lever bites almost straightaway without having to let it out a lot. As the clutch is not slipping I was wondering if perhaps it will be the clutch slave instead but im not seeing any leaks.Any advice ? 2004 r1150rt 50,500 Miles  

17 minutes ago, dougiedickson said:

Hi Guys, Im noticing lately that my clutch lever bites almost straightaway without having to let it out a lot. As the clutch is not slipping I was wondering if perhaps it will be the clutch slave instead but im not seeing any leaks.Any advice ? 2004 r1150rt 50,500 Miles  

Morning dougiedickson

That is usually a sign that your clutch hydraulic system has some air in it. Try a good clutch bleeding with new fluid, if the problem goes way then you had air in the system.

If the problem then returns at a later date  suspect that you have a bad slave cylinder that is pumping air in as it works.