Sticky clutch

[Swanny]

I have a zr550 which is fine when warm but when it's cold I have to rock it back and forth to free off the clutch before I can start the engine and put it in gear, otherwise it stalls.
I changed the oil a couple of weeks ago and used castrol 10/40 oil which the manual says is ok but it's car oil would that be causing the problem??
Is there a difference between car and bike engine oil??
:-/

[whizz]

Hi yea could be the problem car and bike oil have different chemical make up in them ,some which will affect the wet clutch system that your bike uses try changing the oil to proper bike oil ,you may well have to clean the clutch plates too... was clutch ok before you did oil change? have you checked adjustment etc?

[470four]

Hi yea could be the problem car and bike oil have different chemical make up in them ,some which will affect the wet clutch system that your bike uses try changing the oil to proper bike oil ,you may well have to clean the clutch plates too... was clutch ok before you did oil change? have you checked adjustment etc?



What he said :)

May be gumming the plates together, car clutches run dry OUTSIDE of the engine so the oil is different... ;)

[Swanny]

I think it was ok
I will change it thx :)

Not sure how to adjust the clutch except on the handle bars

[silly_simon]

Do the oil change mate and pop it over to me in Westbury and I'll check the clutch adjustment for ya :)

[470four]

Im glad you owned up to putting car oil in, we could have been chasing that one for a while... :D :)

[Mitch9128]

Car oil wouldn't cause that though, if anything at all. Lot's of people run car oils in their bikes to no effect, yes some have additives that 'could' cause slip, but 10/40 is still 10/40 whether bike or car oil, and wouldn't cause the plates to stick.

[silly_simon]

Car oil wouldn't cause that though, if anything at all. Lot's of people run car oils in their bikes to no effect, yes some have additives that 'could' cause slip, but 10/40 is still 10/40 whether bike or car oil, and wouldn't cause the plates to stick.


Its dependant on the grade of oil isnt it ?
And bike oils are specifically for wet clutch's arn't they :-?

[Jon_W]

To be exact, car oils contain large molecules ment to reduce friction on bearings, and detergents to keep surfaces clean. Motorcycle oils do not contain the larger molecules as these can affect the wet clutch and also get obliterated by the gearbox. Motorcycle oils do not also contail as much detergent.

I'd change the oil for the correct type. Don't be tempted to put synthetic oil in if the book asks for mineral or semi either... that will harm the engine seals. Then if it is still playing up it may be that the clutch needs stripping and cleaning out fully.

[470four]

Fully synthetic can also work a little too well in its slippery lubey loveliness & cause clutch slip... :D

My Grandads Triumph managed to stick all its clutch plates together after being ignored for two years, needing a new clutch plate set to work again...

** When you drain the oil out to change it, take the clutch cover off & strip the pressure plate & clutch plates off & wipe them clean, dip them in some new bike oil before refitting thus ensuring they are good to go, so-to-speak ;)

[Cemorah]

Use brake cleaner or petrol to wash the friction plates.

While you are there you could check them all for distortion with feeler guages on a sheet of glass, and check the clutch mechanism for the correct "lift" if given in your manual

[Swanny]

Blimey didn't realise it was so bad to use car oil. :-/ :
I thought I was doing the old girl a favour

Thanks to everyone for the advice I will do it today. Will even have a look in the clutch case :)
Silly thx for the offer that would be great :)

[alanTDM]

Not all car oils are the same I know a few bikers who use GTX 10-40 API SL/CF in there bikes with no problems at all.
GTX has been out for quite a long time now its the newer car oils which are the problem with additives to combat emissions etc which makes them no good for wet clutches you find on bikes as there too slippery,seems anything over API SL/CF is a no go.

[Swanny]

I changed the oil today to a proper bike one. (Semi synthetic)
I chickened out on taking the side case off, will see how it goes now.
Was a bit worried at first after the oil change as it wouldn't put away, it just cut the engine every time I let the clutch out.
But I let it warm up and it was fine.

I'll let you know how it is tomorrow when it's cold again :-?

Thx again everyone :)

[Swanny]

A few days on and some miles on the clock but the problem is still there :-?

[whizz]

Hi ok is problem still same ? plates been cleaned?

[Swanny]

I didn't clean the plates, thought that a good ride might do that...

[simongpz]

all i can say is the clue is in the name car oil for cars bike oil for bikes oil manufactures know what thay are doing bike engines rev a lot higher then car and the oil in cars only has to lube the engine not the gearbox and clutch as well

[Swanny]

I'm not the first to make this mistake and sadly won't be the last.
Oh well life's about learning :)

[silly_simon]

Mate if its still playing up drop it over one Sunday and I will have a looksy at it for you :)

[Swanny]

Thx for the offer :)

Last time I took her out she seemed a lot looser so maybe it's starting to free up

[wiggy]

Hey did you buy that from pitman avenue ? if so thats my old zephy lol .Bless her good bike that clutch allways stuck on it ,my gpz is the same from cold . :D

[Swanny]

Hi Wiggy
I bought her from a chap down at Castle Cary way

[wiggy]

Not the same bike then lol but the gt,s old z,s and zr zephers suffer from sticky clutch ,my gpz does aswell ,i rock it in gear before i start from cold its fine then .If it get on your tits try new plates and a differnt oil . ;)