2016 R1200RT clutch slipping in high gears when accelerating...

[skibumwi]

The clutch on my R1200RT (48K miles, just had the 12K service done) has recently begun slipping a bit when I'm in 5th or 6th gear and try to accelerate quickly. When I try to accelrate quickly in the top two gears the engine revs increase without really speeding up but after a couple of seconds it will grab and accelerate as I expect it to.

Any ideas as to what may be going on? Is there a clutch adjustment that might be incorrect? I Really don't want to spend money on a new clutch after only 48K miles.

Thanks,
Ski

 

[Toruk]

My experience with hydraulic clutch units slipping under high load has been the slave unit needing a good cleaning and fluid flush. The pressure release valve in the slave unit often gets gunked up. That causes it to not fully release and engage. I believe in full hydraulic flushes every 2 years as preventive maintenance.

 

[brownie0486]

My experience with hydraulic clutch units slipping under high load has been the slave unit needing a good cleaning and fluid flush. The pressure release valve in the slave unit often gets gunked up. That causes it to not fully release and engage. I believe in full hydraulic flushes every 2 years as preventive maintenance.

I'm under the impression that BMW's recommendation is a clutch/brake flush with new fluids every two years. My 16RS had only had 2500 miles put on it in two years as I mainly ride the RT. It's 2 year is up in Dec. I called the mechanic and explained the scenario, I'll bring it in in a few months for an oil change [ might as well do that ] while they replace the clutch and brake fluids per the two year recommendation from BMW.

Does it need it with just that many miles on the last service? I don't know, but I do know I keep to their maintenance schedule on all the motors.

 

[alegerlotz]

I'm under the impression that BMW's recommendation is a clutch/brake flush with new fluids every two years. My 16RS had only had 2500 miles put on it in two years as I mainly ride the RT. It's 2 year is up in Dec. I called the mechanic and explained the scenario, I'll bring it in in a few months for an oil change [ might as well do that ] while they replace the clutch and brake fluids per the two year recommendation from BMW.

Does it need it with just that many miles on the last service? I don't know, but I do know I keep to their maintenance schedule on all the motors.

The Clutch on a wethead uses mineral oil, not brake fluid.

Only brake fluid changes are specified in the maintenance schedule.

 

[Omega Man]

I’m wondering if in first or second you notice this when you roll on the throttle? Engine impulses from what is essentially gear selection (fifth or sixth) out of sync with engine RPM’s can cause odd drivetrain problems.

OM

 

[pglaves]

Slipping hydraulic dry clutches generally have one of three causes:

1. Failure of the clutch to fully grip because once released the fluid does not properly return to the master cylinder, leaving the clutch partially engaged. This is rare but possible.

2. Contamination of the friction surface. Sources of contamination could be hydraulic fluid from the slave cylinder; transmission oil from a leaking input shaft seal; or engine oil from a leaking rear engine main seal.

3. A clutch friction disk worn too thin.

In this case I think #2 above is the most likely cause if this is a dry clutch. I am not up on when BMW went to the wet clutch system on all the various models.

If it is a wet clutch then contamination isn't an issue so only #1 and #3 would apply.

 

[PoorUB]

Slipping hydraulic dry clutches generally have one of three causes:

1. Failure of the clutch to fully grip because once released the fluid does not properly return to the master cylinder, leaving the clutch partially engaged. This is rare but possible.

2. Contamination of the friction surface. Sources of contamination could be hydraulic fluid from the slave cylinder; transmission oil from a leaking input shaft seal; or engine oil from a leaking rear engine main seal.

3. A clutch friction disk worn too thin.

In this case I think #2 above is the most likely cause if this is a dry clutch. I am not up on when BMW went to the wet clutch system on all the various models.

If it is a wet clutch then contamination isn't an issue so only #1 and #3 would apply.

Contamination could be a problem if they used incompatible engine oil.

 

[orforester]

Have you seen the procedure to bleed/change clutch fluid? Ya gotta take out the starter! Can BMW make it any harder to do routine or otherwise maintenance on a bike!! I had a Ducati and the bleeder valve was right out there where you could get at it, not buried inside a bunch of parts! Grrrrrrr.

 

[windsailor97]

Contamination could be a problem if they used incompatible engine oil.

This is the first thing I thought of. Wrong oil would cause slippage for sure.

 

[52184]

Have you seen the procedure to bleed/change clutch fluid? Ya gotta take out the starter! Can BMW make it any harder to do routine or otherwise maintenance on a bike!! I had a Ducati and the bleeder valve was right out there where you could get at it, not buried inside a bunch of parts! Grrrrrrr.

On previous models where the clutch slave cylinder was pretty inaccessible, BMW ran a bleeder hose out to a more accessible location, and at the end of the hose had a grub screw that could be removed and replaced with a bleeder or a fill fitting. (think brick-k models). Why not on the wethead? Cost? Insufficient space in the starter area? Unnecessary due to extremely long flush intervals for the mineral oil used in the clutch system? Or just simple oversight?

Best,
DeVern

 

[strataj]

On previous models where the clutch slave cylinder was pretty inaccessible, BMW ran a bleeder hose out to a more accessible location, and at the end of the hose had a grub screw that could be removed and replaced with a bleeder or a fill fitting. (think brick-k models). Why not on the wethead? Cost? Insufficient space in the starter area? Unnecessary due to extremely long flush intervals for the mineral oil used in the clutch system? Or just simple oversight?

Best,
DeVern

DeVern my 02R1150RT had the above set up, it was easy to change and flush, I even had a speedbleeder. That was Dot 4, BMW service change every 2 years. As said earlier the Wethead uses Mineral Oil and no service requirement.

 

[skibumwi]

Some Clarifications

- All of the 12K Services have been performed at the dealer with OEM fluids
- I've never had it occur in gears 1-4, only 5 or 6 when I've been riding in the gear and try to accelrate quickly (such as passing).
- I checked the fluid reservoir and it was full


Ski

 

[brownie0486]

- All of the 12K Services have been performed at the dealer with OEM fluids
- I've never had it occur in gears 1-4, only 5 or 6 when I've been riding in the gear and try to accelrate quickly (such as passing).
- I checked the fluid reservoir and it was full


Ski

Mu understanding on clutch fluid in the container is supposed to 1/2 full. When they get to full capacity, clutch issues.

Is this not correct?

 

[pglaves]

Mu understanding on clutch fluid in the container is supposed to 1/2 full. When they get to full capacity, clutch issues.

Is this not correct?

Yes. As the clutch wears the hydraulic fluid level rises. If too full the clutch can hang up only partially engaged.

 

[BC1100S]

Mu understanding on clutch fluid in the container is supposed to 1/2 full. When they get to full capacity, clutch issues.

Is this not correct?

That was true on dry clutch BMWs. I believe that wet clutches, like those on the OP's bike, are different. Having said that, it wouldn't hurt to ensure the fluid level in the clutch reservoir is at or slightly below the "full" line.

More questions:

- do you tow a trailer?
- do you travel mainly fully loaded and with a passenger?
- is most of your riding in town?
- do you participate in the "stop light grand prix"?

Any or all of the above can have an effect on your clutch.

 

[strataj]

I remember something about overfilling the clutch fluid on the early wetheads. They came from BMW that way. Mine was one of the first bikes to come to the USA, it's clutch has too much fluid. This was over 9 years ago, sorry I can't recall what issues it caused. I removed some of the fluid, I do remember my clutch had no issues when I trading her in on a 22R1250RT.

 

[skibumwi]

Updates

My riding is almost exclusively one-up, no trailer, no drag racing, and the only city driving is getting out of town.

Re-checked to fluid level an it is fine, on my initial check the bike was warm and the fluid started leaking out before I could get the 4th screw out. This time the engine was cold and the reservoir was about 1/2 full.


Guess I'm going to have to bite the bullet and take it to the Good dealer in the Houston area, the one in Katy (45 miles away) instead of the Woodlands (5 miles away).

Ski

 

[pglaves]

Re-checked to fluid level an it is fine, on my initial check the bike was warm and the fluid started leaking out before I could get the 4th screw out. This time the engine was cold and the reservoir was about 1/2 full.

Ski

If I understand this correctly, when hot the hydraulic fluid was so full that it might have actually been pressurized but in any case was overflowing when you removed the lid.

If so this condition could easily cause the clutch slipping once the system was hot.

I would recheck the system when hot and if still full reduce the level a little bit.

 

[BC1100S]

Re-checked to fluid level an it is fine, on my initial check the bike was warm and the fluid started leaking out before I could get the 4th screw out. This time the engine was cold and the reservoir was about 1/2 full.

Something is not right with that. Fluid should not be expanding that much with heat and, as Paul mentioned, could be the cause of the slippage. My money says your clutch isn't worn out.

 

[skibumwi]

So, today I re-checked the fluid level when cold - it was just over half full. I removed about 1 tsp of fluid, went for a short ride and the same issue occured. I doubt it's the fluid level.

Ski