I looked at the Chain Gang and someone there has a possible explanation: if you use part synthetic oil as the clutch is a wet clutch, running in the engine oil, it is prone to slipping. Someone else says you should just use pure synthetic oil.

My experience of slipping clutches leads me to believe that once they've started to go, you need a new set of plates and springs. It's only a few quid to switch to normal oil though so worth a try but I doubt it'll help.

In my CS manual it says "Attention: do not use synthetic oils". But other than that it only specifies that it meet SF/SG/SH+CD/CE, or, G4/G5+PD2. I used to go through a clutch every 20,000 miles on my old bike, the chains would last longer and that was with mobil1.

 

Before I take the engine to bits to get the clutch out (according to the Clymer manual, you go through Chapter 5, removing the engine, to get at the clutch, which surely can't be true?

Certainly not on mine (CS). It' accessible from the left engine cover. Though I have to drain the coolant, engine oil and remove the exhaust and gear selector lever.

 

I've only changed my oil once, and bunged in my old favourite Castrol GTX. I started to get some clutch slip but it settled down after 100 miles or so and I have no trouble now.
I'd overlooked the fact that on the F650 the clutch runs in the engine oil, whereas every other bike I've had for ages the clutch is dry or runs in the lighter primary chaincase oil.
I think I might go for "proper" motorcycle oil for the F650 next time to be on the safe side.

 

I've just changed the engine oil, out on the prom in sub zero temperatures blowing half a gale. I bunged in something called 'Castrol Merit' which is just a straight 20/50 SF grade, and half the price of GTX. I chucked the drained oil into my Transit.

Warning to anyone changing oil: it pours / drips out of three separate orifices - frame, sump and filter housing. Do it out in the road, preferably where motorcyclists are not going to go, because although I used a paint roller tray to catch it, the oil spreads itself over about half a square metre of ground. So if you are Green, you had better get a bag of cement handy to soak it up.
I'll post the result of whether it has an effect on the clutch slip - it is far too cold to go for a ride now. :howdy:

 

Andrew(gasgas),
Castrol GTX used to be the oil of choice for BMW I believe! Works alright for me anyway
If your clutch is slipping make sure the cable/arm is correctly adjusted, I've had to move the arm round one spline on mine. The setting up / measuring is in the manual and colour pictures are on the Chain gang site.
If you want a hand give me a shout.

Chris
PS We better arrange going for a drink to go over the plans for the ride away! :dance:

 

Clutc Slip & Engine Oil

The Chain Gang www.f650.com ran this thread some time ago. It would seem that engine oils with th EC (Energy Conservation?) designation had
some anti friction additive which upset the clutch,as it works by friction, and makes it slip. Fully sythetic is one solution or a plain 20/50 without the EC additive - Duckhams Hypergade I think is ok. But yes the oil can effect clutch slip it happend to my 98 F650 - I changed the oil straight away and all was well.
I have also had the clutch side engine cover off for powder coating - this exposed the clutch and i was able to access the plates, all this without taking the engine out
Matt

 

On the way to work today espically when in top gear it felt that my clutch was slipping a bit as well. just didn't feel right from 5000 revs up at full throtle.

would adjustment effect the clutch in this sort of way or would it more likely be something to do with the type of oil that the garage used when they serviced the bike before I picked it up?

Cheers Guys

Kiwiboy

 

Kiwiboy-
I have changed the oil in mine for standard Plonko oil, but the weather has prevented me from trying the result. I reckon that standard oil, like GTX should be used and not anything synthetic or with additives. You could ask the garage what oil they used.
Before you change the oil, check the clutch free play, as priesty says. There should be some noticeable slack in the clutch lever before you feel some resistance in pulling it back to the handlebar. You dont need the engine running to do this. For dimensions and measurements follow Priesty's instructions.

 

Cheers gas gas

I went and had a chat to the garage on saturday they, they said that they put 10-40 semi synth oil in the bike.

would this sort of oil cause the clutch to slip?
:think:

Cheers

Kiwiboy

 

I've only changed my oil once, and bunged in my old favourite Castrol GTX. I think I might go for "proper" motorcycle oil for the F650 next time to be on the safe side.

Is a car oil like GTX a good idea for a bike with a wet clutch and without separate gearbox lubrication? I thought that the difference between car and bike oils was that the latter is designed for wet clutches and getting thrashed by the gears.

 

Kiwiboy-
I also had semi synth oil in mine. I have now had a chance to do a run with the Plonko oil, and it slips even more now, and jumps out of second gear into neutral.

 

I can't believe that nobody has mentioned the importance of using motorcycle specific oils!!!

Car oils, like GTX, contain friction modifiers that will totally screw a wet-plate clutch.

Use a high grade semi or fully synthetic oil to the speciification listed in the bike's manual. Tip in car oil, buy a new clutch! Simple as that!

Greg