Hydraulic Clutch Slave Cylinder Maintenance

[sykospain]

Decided to have a go at the Clutch Slave Cylinder access job this weekend.

I just had to remove the pesky cross-bar though, after peering in from the back end ( oo-er ).

Job's so much easier on our nakeds when you don't have all that Tupperware and all those rear frame securing bolts to remove - just the four and slacken the pivot bolt's nuts, one each side.

But I think that ANY old boxer needs this job, whether it's a roadster, a GS or an RT, if it's got more than about 15K miles on the clock and you don't know whether the fluid has been flushed regularly.

See my vodiodi of the job...



https://youtu.be/8TQ1nTleSYU

AL in s.e. Spain

[sykospain]

Follow-up...

So what about this contaminated seal deep in the 5cm cavity that the slave cylinder sits in ?
How does one get it out so as to insert the new ¿ orange ? one ?

Chris Harris has a video from a few years ago mentioning this contaminated seal but he doesn't mention or show there, exactly how to get the soiled one out and the new one in.

Any help would be appreciated..

https://i.postimg.cc/3xr4SD46/Clutch_Sl ... poo.jpg

AL in sunny Andalcuía.

[Photoguy]

Would the old trick of inserting a wood screw into the seal and prying it out work?

https://www.youtube.com/watch?v=Ehqz1Y-ggGo

[BadToTheBown]

My seal was frozen in my cylinder. Nothing made it move. So I took it to a machinist friend of mine for ideas and it turned out to be dead simple. Put a socket on it and smack it hard. Mine was really locked to the cylinder wall. I used the socket to hold it down, pulled the C-clip and it came apart (still a little stubborn). Cleaned up the cylinder wall good with brake cleaner and back together with silicon grease and make sure you put the seal in right, it's directional. Good luck...

[sykospain]

Yes, BadtotheBown, you're talking about the angled rubber seal inside the actual slave cylinder.

No, I'm talking about the gearbox seal that sits deep in the cavity that the Slave Cylinder unit sits in.
Two different seals.

This is it - described as the "Gearbox Output Shaft Input Seal". It's contaminated with a foul-smelling mixture of gearbox oil, hydraulic fluid escaped from the slave cylinder and some cylinder bearing grease. It's been removed by another inmate, "Slipperyeel" of the UKGSer forum and is a sorry sight.

https://i.postimg.cc/RFJ76wNp/Gearbox_i ... ged_01.jpg

[sykospain]

And this is what lies behind it that pesky, hard-to-rip-out Input Seal :-



Scratches ? Wot scratches ? ?



And when you finally see that roller bearing, and successfully insert the new brown-coloured Viton new-style seal right in front of it ( ¿ How ? )....

...you're supposed to drill a small weep hole in the lower face of the gearbox casting, so any excess DOT4 from a future-failing slave cylinder can drain harmlessly out downwards to avoid the stuff filling up the cavity and sashaying along the long actuation push-rod to wreck your friction plate....

...from exactly wwhere do you source a 20cm long 2mm drill bit for the job, when the lower lip of the gearbox casting and the swing-arm assy are both in the way of your portable drill's chuck ?

Only asking....

AL in Andalucía

[BadToTheBown]

Never had to do one of those, my bad on commenting on the wrong seal...

[sykospain]

Three or four weeks later now - into early December - and both bikes' slave cylinder replacements, along with their inner cavity seal in the back of the gearbox - are completed.

Fitted one of the newly-sourced longer-hubbed clutch plates into Motorcycling Mo's year'04 GS-A and he says it now shifts like silk. As well as a new handlebar-to-slave braided hose as I did on my Rockster.

A job well-worth doing as the cavities for the slave cylinder in both bikes were contaminated to varying degrees with the smelly dingle of gearbox oil and escaped DOT4 that had leaked past the banjaxxed slave cylinder piston seal.

As memtioned oftentimes before, never hesitate to lift off the lid of your clutch master cylinder on the handlebar and see whether it's clear or muddy. In the latter case, do this job straightaway.
AL in s.e. Spain
PS - to the Moderators - Above I used the word for a mixture of liquids that's common in bars and among drinkers. But because it starts with the letters see oh see kay, your stupid software thinks it's a profanity and dotted-lines it. Sort it out please !

[Hoof]

I had a slipping clutch in high gear...oil visible in the clutch housing behind the starter motor.........Following the wonderful clutch access instructions from Al ( I numbered each operation & had a check list of 36 items! )
Thank the lord for the humourous comments which saved me from despair as the bike looked as if it had exploded!
On the way I discovered the clutch Push Rod to be covered covered in black sludge. I noticed the gearbox oil-seal hidden deep inside the Slave Cylinder cavity at the back of the gearbox casting seems to be set behind a step/lip on my r1150r - It LOOKS ok but because of the step does this mean this seal can only be replaced from the inside and not 'pulled' over or a new one re-inserted over the step from the outside?

[Hoof]

That excellent picture seems to clearly show that there is no step or lip retaining the input seal.- it looks as if there is a lip with the old seal in place but the photo shows that the seal housing is just a narrower diameter - no lip ....so the old seal pulls out and the new one IS a push fit from the outside.....

To drill the drain hole - Hex shank bits will fit into a drill extension. May even be long enough with the hex screw bit holder. I hope - haven't done it yet!