Help- Hydraulic Clutch Problem??

[Randyjaco]

Due to a slipping clutch, I am in the midst of replacing the clutch disks. I removed the old disks and carefully by the BMW instructions replaced the new ones. Everything appeared to be fine. I went ahead and torqued the 3 clutch spring bolts and tried to actuate the clutch lever. The lever would not move. OK, I probably stacked the disks wrong. So, I redid the disks. The clutch lever still didn't move. This time I removed the disks and tried the clutch lever again with the clutch disassembled. Still no movement. The clutch lever feels just like a brake lever at full stop. The hydraulics are functioning, but there is something preventing the actuation of the clutch. Any ideas on what the problem might be? I have never had any problem with the hydraulic clutch mechanism before. Evidently I executed another rookie mistake somewhere.

 

The bike is a 2017 R1200RT

[Bernie]

Is the fluid reservoir for the clutch overfilled? Or the push shaft from the clutch slave cylinder has been unseated. 

Looking at the instructions it says that the last friction plate has to be offset by one tooth.

 

	ATTENTION
Friction plates installed with offset Component damage   Only the last friction plate has to be installed offset by one tooth.

Install thrust piece (1) and pressure plate (2), making sure that only last friction plate (3) is installed with an offset.

 

 

Edited March 31, 2023 by Bernie

[dirtrider]

57 minutes ago, Randyjaco said:

Due to a slipping clutch, I am in the midst of replacing the clutch disks. I removed the old disks and carefully by the BMW instructions replaced the new ones. Everything appeared to be fine. I went ahead and torqued the 3 clutch spring bolts and tried to actuate the clutch lever. The lever would not move. OK, I probably stacked the disks wrong. So, I redid the disks. The clutch lever still didn't move. This time I removed the disks and tried the clutch lever again with the clutch disassembled. Still no movement. The clutch lever feels just like a brake lever at full stop. The hydraulics are functioning, but there is something preventing the actuation of the clutch. Any ideas on what the problem might be? I have never had any problem with the hydraulic clutch mechanism before. Evidently I executed another rookie mistake somewhere.

 

The bike is a 2017 R1200RT

Afternoon Randyjaco

 

See Bernie's post as a first thing to look at.

 

From what you posted it sounds a lot like your pressure plate is out too far therefore allowing the slave cylinder piston to bottom out in it's travel. This is sort of confirmed by no clutch lever movement even after clutch disassembly.

 

So make sure that you have the small (short) outer push rod installed  correctly  (or that it isn't missing)  and that your new clutch pack isn't too thick (like an extra plate installed or a plate or two installed incorrectly).

 

If still no smoking gun then maybe try match your old clutch pack total thickness up to the new clutch pack total thickness.  

 

 

[Randyjaco]

Thanks for the quick replies. I am thinking that it must be the slave cylinder push shaft. If I have the clutch disassembled and pull the clutch lever. Shouldn't the lever move freely? With the clutch assembled or disassembled, I get no movement.

Any suggestions on aligning that shaft? I have never touched that slave cylinder before. I was also very careful to not disturb the brake or clutch levers prior to testing the clutch. I am baffled as to why the lever is not functioning properly?

 

Fluid level has never been disturbed since new and the clutch has always functioned properly up until now.

[dirtrider]

25 minutes ago, Randyjaco said:

Thanks for the quick replies. I am thinking that it must be the slave cylinder push shaft. If I have the clutch disassembled and pull the clutch lever. Shouldn't the lever move freely? With the clutch assembled or disassembled, I get no movement.

Any suggestions on aligning that shaft? I have never touched that slave cylinder before. I was also very careful to not disturb the brake or clutch levers prior to testing the clutch. I am baffled as to why the lever is not functioning properly?

 

Fluid level has never been disturbed since new and the clutch has always functioned properly up until now.

Evening Randyjaco

 

Shouldn't the lever move freely? With the clutch assembled or disassembled, I get no movement.--- Yes & no, depends on WHERE (in it's travel) the slave cylinder piston currently is.

 

If the slave piston is pushed back in it's bore then, yes, the piston should move & the hand lever should move when it is pulled. 

 

On the other hand,  If the slave piston is all the way out (to it's out-stop) in the bore, then the piston will not move & the hand lever will not move much when it is pulled (will feel like a fully applied brake lever) . 

 

In your case it sounds like you have the latter, if the slave piston is already all the way out then it will probably feel like your clutch does now. 

 

The question is WHY? Is that short pushrod installed? Is it installed with short end facing out?  Is your new clutch pack way too thick? Is the pressure plate installed correctly?  

 

Without seeing it I am basically guessing here but it sure sounds like something is installed incorrectly, or is stacking up to allow the slave piston to be pushed out in it's bore too far. Can you tell if the pressure plate springs are near full compression? If they are near or at full compression before pulling the clutch lever then something is wrong with your clutch pack height or improper installation.

 

If the springs are not near full compression then possibly the problem is in the push rod area. 

 

Just a thought here_________  ANY CHANCE that someone has messed with the clutch lever pushrod (between clutch lever & piston)? If the master cylinder piston is not FULLY returning all the way out in the bore then it can trap fluid & hold the slave piston fully extended.  This could also have caused your clutch slippage as it doesn't allow full clutch pack engagement pressure. (just something to look at & beware of) 

[Randyjaco]

Thanks again guys. You got it and it was a rookie mistake  Over the years I have done quite a few clutches, but none on a BMW and none hydraulically operated. I didn't think about the self adjusting feature in the hydraulic. I have a cable mind set. So, however the lever got actuated (it was literally 7' in the air), it was limit locked. Once I figured that out what was going on, the rest was pretty easy to figure out and I think I got done.

Tomorrow I will fill her up with oil and verify my work 

 

[BamaJohn]

I'm incredibly impressed with the willingness of people on this forum to help with learned advice!  Even though I was only a bystander, thanks to Bernie and Dritrider...you guys ROCK!