Slippy clutch

Yes, I have some "free play" before the clutch lever starts to operate the hydraulics. No fouling of lever on had guard either.
 
Roymondo
I had exactly the same with my bike took it to the dealer and they repaired it, but they did not tell me what they did! I don't know if they replaced the clutch or what. They guy at the shop was indicating that it was something to do with the clutch pushrod?? But what ever they did sorted it nicely at no cost to me.
 
Pah! Went for a long ride today, and by the end of it I could induce clutch slip at will by simply cracking open the throttle at 70mph in top gear. Back to the dealer I go...
 
Hi Roymondo
Yes get it back to them and take no cack its Fk'd. I bet they knew that when you took it back to them the first time, why do they treat customers like A) they are idiots and B) they are unimportant ?
 
My clutch (2010 bike) was replaced under warranty at 7k miles.

Slip happened at between 100-110mph on my private road in 6th gear.

No fault was found in the clutch which was removed, but replacement cured it.
 
Curioser and curioser...

The original clutch was replaced under warranty last year, when the technician noticed it "starting to slip" while test riding for unrelated vibration and general hesitancy/rough running. I had not noticed it.

Then a few weeks ago, towards the end of a long day out on the road, it started slipping again. The dealer test rode it (twice) and found no slip. They also physically inspected what they could through the starter motor aperture and found no faults.

Then this last weekend, again towards the end of a long day on the road, I noticed it slipping again. This time I found I could provoke it to slip almost on demand, by simply banging open the throttle at 75mph in top. Next morning (i.e. today) I rode it to work and, with only five miles or so ridden from a cold start, found that the slipping was even worse when I tried the above procedure (cracking open the throttle at 75 in top caused the revs to rise by a good 2000rpm). So I called the dealer while I was at work and booked it in.

Now just a few hours later, I have repeated my experiments on the same stretch of road, and find that it doesn't slip at all...

I'm wondering if the long ride is a significant factor? Slight oil seepage that is worse when everything is hot, leading to contamination of the clutch plate? Maybe it gets burnt off or something on shorter trips?

I'm in a bit of a quandary now - The dealer will doubtless check it all over and find no slip. Then on my next long ride the slipping will show up again - only by now the warranty will have expired...
 
Exactly the same symptoms as my 2008 GSA, the clutch only slips a little at high rpm when pressing on in the higher gears during extended 'spirited' riding eg multiple 'A' road overtaking on a ride out. A small roll-off and re-apply throttle and its fine. Have done all the usual checks and drained a little from the clutch master cylinder.
 
I am wondering do you have too much fluid in the clutch master cylinder reservoir thereby not leaving enough room for expansion when there is significant heat build up?


Curioser and curioser...

The original clutch was replaced under warranty last year, when the technician noticed it "starting to slip" while test riding for unrelated vibration and general hesitancy/rough running. I had not noticed it.

Then a few weeks ago, towards the end of a long day out on the road, it started slipping again. The dealer test rode it (twice) and found no slip. They also physically inspected what they could through the starter motor aperture and found no faults.

Then this last weekend, again towards the end of a long day on the road, I noticed it slipping again. This time I found I could provoke it to slip almost on demand, by simply banging open the throttle at 75mph in top. Next morning (i.e. today) I rode it to work and, with only five miles or so ridden from a cold start, found that the slipping was even worse when I tried the above procedure (cracking open the throttle at 75 in top caused the revs to rise by a good 2000rpm). So I called the dealer while I was at work and booked it in.

Now just a few hours later, I have repeated my experiments on the same stretch of road, and find that it doesn't slip at all...

I'm wondering if the long ride is a significant factor? Slight oil seepage that is worse when everything is hot, leading to contamination of the clutch plate? Maybe it gets burnt off or something on shorter trips?

I'm in a bit of a quandary now - The dealer will doubtless check it all over and find no slip. Then on my next long ride the slipping will show up again - only by now the warranty will have expired...
 
I appear to have around 1/4" of airspace above the fluid level in the reservoir. Of course, this might well all be taken up when things get hot? Can't say one way or the other without going off for a 2-300 mile ride (which I don't really have time to do in between working, eating, sleeping and other family/social activities :augie

I am going to write out a full account of exactly what I have experienced (and when, how etc), and my thoughts as to what has and has not happened and might be significant. I will hand this to the dealer on Saturday, so that they have all the facts (and associated opinions) to hand when deciding how best to tackle this issue.

I've tried to provoke the clutch into slipping numerous times over the last two days, but it has behaved impeccably :nenau
 
Well, i was quoted £445 all in today, to replace the clutch if nothing can be found that isnt covered under the warranty. However if they find anything it will be covered in its entirety.
 
I had exactly the same symptoms with my bike. It needs a longish run to warm everything up before it starts to slip. Good thing the service manager at my local is a clued up guy. He asked me if he can have the bike for a day or so to give it a longish ride on his way to work and back. I agreed as I know him quite well. In the end the clutch and slave cylinder was replaced which cured the fault. He recons the slave cylinder leaked and contaminated the friction material of the clutch. You will not spot this with a visual inspection through the starter motor hole. All done under BMW goodwill as the bike was just out of warranty. I just paid for the spares. Everybody happy.

Just might add that the clutch had enough material on it to last a good 30 - 40k extra so basically just bedded in. Bike had done about 14000 mls at the time. When they open it it is worth having a look at the gearbox seals and if the clutch dust inside is a bit sticky to the casing then some fluid is leaking from somewhere. The flywheel did have a bit of discoloration on it but not abnormal.
 
Thanks for that, Tanneman. All will hopefully be revealed next week as the bike is booked in for Monday.
 
Thanks for passing on that knowledge Tanneman, I have exactly the same symptoms so will price up a new slave cylinder and some Vitamol V10 for my bike. :thumb2
 
He recons the slave cylinder leaked and contaminated the friction material of the clutch. You will not spot this with a visual inspection through the starter motor hole. .

Very easy to check. Undo the two bolts that hold the clutch slave cylinder to the rear of the gearbox and pull the slave cylinder back.

If gear oil or clutch fluid runs out the cause of the problem is solved. Then all you have to do is fix it.
 
I also have the same issue with the clutch on my GS, 14K on the clock, have only had the bike a month, I did find that the adjuster was screwed out to far (no slack) and I think that the end of the lever was touching the hand guard.
I checked the fluid and that seems fine.
The clutch only slipped for a brief moment in top when given a big handful.
I had a similar thing with a 1200 bandit from years ago, i cured this by using bog standard Motul oil rather than synth, but as the BMW is a dry clutch I am surprised that anyone could damage a clutch in just 13k.
 
A pal of mine uses way too many revs when pulling away and moderates his speed on the clutch race (2-stroke technique except he's never had one). His Yamaha FZS600 has coped well but he rapidly fried the clutch in his diesel car.
 
Took Steptoes advice: Mine is dry as a bone when removing the slave cylinder, I'm now suspecting it sometimes catches on dry splines and fails to fully re-engage after shifting gears. The intermittent slip I experience can't be replicated at will under normal riding.

Shocked at the price of a full clutch kit at £400+ (compared to a car dry clutch kit typically around £100 but I guess thats just the economies of scale).

A job for next winter to strip and inspect the clutch, see if anything is amiss and lube the splines, replace leaking oil seals and/or replace the full clutch or just friction plate depending what I find. My garage is like a building site at the moment and I'm 'financially challenged' until I start my new job so it will have to wait.
 
An update - Mine has now had (another) new clutch and this time for good measure they have renewed the slave cylinder. They say it wasn't leaking but they reckoned there was a tiny bit of "notchiness" detectable towards one end of the piston's travel. Their theory being that *maybe* the notchiness was worse when things got hot.

Oh, and they also replaced the exhaust flappy valve and its servo (that's the third replacement valve and the second replacement servo in 22000 miles...).

I'm getting the bike back tomorrow (in the meantime I have enjoyed putting a few hundred miles on their F800GT demonstrator, which has been quite a hoot)
 


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