Clutch slip

[Tam]

Recently had my bike serviced at BMW and noticed the clutch slipped twice on a run today.The oil was changed during the service and the oil covers all the sight glass.Could over filling oil have caused this possibly putting extra pressure on the seal between clutch housing.The bikes done 30000 miles.

 

[DrFarkoff]

What year?

Check the handgaurd is not holdin the clutch lever on very slightly

It is enough to make it slip!

 

[fizzer]

Recently had my bike serviced at BMW and noticed the clutch slipped twice on a run today.The oil was changed during the service and the oil covers all the sight glass.Could over filling oil have caused this possibly putting extra pressure on the seal between clutch housing.The bikes done 30000 miles.

i dought the overfill would would have worked its way through the seal,but what you could do is take a bit of oil out down to where it should be,then take the starter motor off and take the plugs out ,rotate the engine with the back wheel and spray some brake and parts cleaner onto the clutch ,and see how that goes over the coming weeks ,if it dont work you will have to put a clutch in

 

[mikeyboy]

What year?

Check the handgaurd is not holdin the clutch lever on very slightly

It is enough to make it slip!

This!

 

[Tam]

It's 2010 .The hand guard has loads of clearance..
Thanks for that Fizzer I hope not to be replacing the clutch...Very intermittent The bike done this when I first bought it so took it to a garage and they assured me the clutch was fine. (Not the same place I bought it). Was fine all last summer.The bikes been sitting all winter today was its second run of the year.Could it be with sitting for 5 month?? Possible small oil seal leak..??

 

[fizzer]

a few years ago my old rockster did the same ,just every now and then it did it .i did spray the clutch with parts cleaner and it worked for well over a year ,but in the end ,you guessed it ,i had the gearbox out

 

[mikeyboy]

It's 2010 .The hand guard has loads of clearance..
Thanks for that Fizzer I hope not to be replacing the clutch...Very intermittent The bike done this when I first bought it so took it to a garage and they assured me the clutch was fine. (Not the same place I bought it). Was fine all last summer.The bikes been sitting all winter today was its second run of the year.Could it be with sitting for 5 month?? Possible small oil seal leak..??

Bit of a bugger to get to,pop the clutch slave off and check for fluid loss, or the rear input shaft seal leaking.
Any oil can travel down the hollow input shaft ,inside which the clutch push rod lives,this will soon contaminate the friction plate.
1200 clutches are not cheap

 

[Tam]

I have a big trip planned later in the year do slippling clutchs slowly get worse to the point it slips every gear at low revs or can they just let go with no warning.It takes higher revs before it slips and even then not all the time or its hard to replicate the same point to make it slip and the bike done 6500 mile last year between slips

 

[DrFarkoff]

Okay start with basics and do not jump to conclusions

It used to be that the ball end of the lever would catch on the edge of the groove that is there for it, holding it on just a mm making the clutch slip under load when warm

If this is what you checked then check the lever adjustment that someone hasn;t seen a whirly knob and give it a twist! and shortened the biting point

@ 30K unless its the above or oil it should not need a clutch

It's 2010 .The hand guard has loads of clearance..
Thanks for that Fizzer I hope not to be replacing the clutch...Very intermittent The bike done this when I first bought it so took it to a garage and they assured me the clutch was fine. (Not the same place I bought it). Was fine all last summer.The bikes been sitting all winter today was its second run of the year.Could it be with sitting for 5 month?? Possible small oil seal leak..??

 

[Steptoe]

i dought the overfill would would have worked its way through the seal,but what you could do is take a bit of oil out down to where it should be

A bike filled with the correct quantity of oil specified will cover/fill the oil sight glass so no need to remove any oil just so you can see the level in the sight glass.

 

[duckspeed]

What year?

Check the handgaurd is not holdin the clutch lever on very slightly

It is enough to make it slip!

Thought mine slipped last time out, just been out to the garage and guess what the lever has been in contact with the hand guard, long enough to have left witness marks.
I had been considering having the bike in bits to investigate, think I shan't bother now.

 

[Bendy toy]

I overfilled my oil when I convinced myself it was under filled after an oil change. It was just normal but oil was clean. The excess oil caused the exhaust to blow blue smoke on startup. Nothing more. Soon enough the excess was gone.
Was there a risk of hydraulic lock? Possibly yes, but stopping the starter motor after 1/2 a crank turn standing start won't do any harm. Not advisable but not catastrophic.

Another reason for clutch slip is too much oil in the reservoir. The level rises as the clutch wears.

Oil contamination generally causes a dry clutch to judder. Slipping happens later as more oil gets deposited.

If you do need a new friction plate also replace the gearbox and engine oil seals.

The engine designers thoughtfully provided a clutch access cover. Sadly the chassis designers made it impossible to easily remove the air box to take a look.

 

[Tam]

Thanks for the info ,much appreciated.

 

[Steptoe]

I overfilled my oil when I convinced myself it was under filled after an oil change. It was just normal but oil was clean. The excess oil caused the exhaust to blow blue smoke on startup. Nothing more. Soon enough the excess was gone.
Was there a risk of hydraulic lock? Possibly yes, but stopping the starter motor after 1/2 a crank turn standing start won't do any harm. Not advisable but not catastrophic.

I've had a bike in with the engine filled, and i mean literally filled with oil.
He couldn't see any level in the sight glass (because it was already full) so emptied a whole 4 litre container of oil into the engine.
The bike still ran ok but was spluttering oil out of the exhaust pipe when you revved the engine

 

[Greenman14]

I wouldn't do anything drastic yet if it's only slipped once. Just keep riding and do the occasional clutch slip test, if the test regularly results in slip then worry!

 

[Delboy777]

Top gear, 4-5k revs open throttle all the way, if it slips it slips. They will do that for long enough till clutch is fecked, ive even heard of them "sorting themselves" out too. Unlikely to be oil on plate.

 

[Tam]

That's exactly what it's doing Delboy.Whats causing it to slip if it's not oil and only done 30000

 

[Tam]

How do you do that Green man. Top gear and full throttle. Or is there another way.

 

[Greenman14]

Delboy has it spot on.

 

[DrFarkoff]

Seriously Do NOT Slip these clutches!

You will end up with needing the whole assembly and the clutch pack for a 1200 is £400 or thereabouts!

Tam "Did you check that the wee knurled knob is wound out and not in ??

How far off fully released is your clutch releasing?? 1 mm ?? 5 mm??