1400GTR Clutch Issue

[tony1968]

Hi all, my 2008 GTR is having clutch issues, after about 40min riding, the clutch lever is loose except for the last 10mm which will operate the clutch. A further 20-30min and it slowly comes back to normal? I have done a flush and bleed, no difference?

Any advise appreciated.
Tony

[virginiajim]

I've had that happen to me a couple of times.  Bleeding the clutch lines and clutch master cylinder usually helps, but be aware the clutch can be very finicky to bleed.

[tony1968]

i HAVE PUT NEW FLUID THROUGH AND BLED THIS UP. 99% OF THE TIME THERE IS NO PROBLEM. oNLY HAPPENS ONCE PER RIDE AS WELL???

[virginiajim]

No, it's usually about once every couple of years for me.  Could be the master or slave cylinder at fault.  Did you bleed the bleeder on the master itself?

I'm also thinking that at the bottom of the master there should be two holes, one large one very small.  The small one can get crudded up.  Open up the top of the master cylinder and squeeze the lever very gently and see if there is fluid movement near that small hole.  If not it may be plugged.  Find a very small wire to fit that hole and try to make sure it's open.  If if the hole has fluid movement it might not be a bad idea to run the wire through it anyway.

[tony1968]

?? No, put new fluid in and pushed it all the way through, never letting it run out of course.

[virginiajim]

See above..more information added.

You should bleed all of the bleeders, not just the one on the slave.

[Macskwak]

You know what the slave and master plungers are so cheap i would replace both and be done with it. You cant mess about with brakes its literally life or death so dont waste anymore time wondering 👍👍👍😁

[tony1968]

Macskwak - Clutch not Brakes.

[Wookie]

It is highly probable on a 2008 bike that what you are experiencing is fluid blowby on the master cylinder rubbers . A new set will sort that out nae probs .

[virginiajim]

And that..

[tony1968]

OK, done a bit of research on oils, seems many people don't like the Penrite MC4 Fully Synthetic, anyone had issues?

[Freddy]

Why is that?  As that's an engine oil, how do you/they reckon it's affecting the lever funbction?

[O.C.]

It's not unheard of for Fully Synthetic oil to cause clutch related problems

The manufacturers generally do not recommend the use of fully synthetic oil...so I would not recommend its use

Try changing the oil for one with viscosity rating of SAE 10W-40 type  API SG, SH, SJ, SL or SM with  JASO MA, MA1 or MA2...THIS INFO IS COPIED FROM THE OWNERS HANDBOOK     

[shaggs147]

Wouldn't the engine oil have more to do with clutch slip rather than the lever issue? If you are absolutely certain that you have got rid of all the air then I'd probably start at the master cylinder and get a repair kit for it and go from there. I think Boomer has had his clutch apart so he will probably have more info on it for you.

Sent from my SM-G920F using Tapatalk

[Wookie]

 Yep Wook has heard of fully synthetic causing clutch slip .. but on further invetigation it transpired that folk had put car fully synthetic in to safe a few quid and Lo and behold car oil has FRICTION INHIBITORS.DOH!
Anyhoooo I have used fully synthetic M.C oil over tens of thousands of miles with no probs at all .
Some times I even if planning to ride thru the winter swoped back to semi synthetic  .. with no probs .
If the clutch on this bike is slipping then it's new friction plates ..and possibly drive plates if blued.
That is assuming all seals and rubbers (no not the sort ya slap on ya todger ) have been changed and are in good order .
Just as an after thought .. if dot 3 has been used in a dot 4 system .. that would screw the pooch totally !
Hope this helps from Wooks repository of fek ups